Complete Fracture-Dislocation of the Thoracolumbar Spine with No Critical Neurological Deficit: A Case Report.

Fractures at the thoracolumbar junction are the most common spinal column fractures. Among type C fractures in the Arbeitsgemeinschaft für Osteosynthesefragen Spine Classification, cases with complete fracture-dislocations of the spinal column often result in a critical neurological deficit despite surgical treatment. We present a case of an 18-year-old man who had a complete fracture-dislocation of the T12 vertebral body and multiple injuries following high-energy trauma but no critical neurological deficits. Because of active bleeding in the left thoracic cavity, the patient underwent open reduction of the T12 vertebral body and anterior spinal fusion of the T11-L1 vertebral bodies via an anterior approach between the T9 and T10 ribs within 24 h of the accident. Four months postoperatively, the patient could ambulate independently, with a slight disturbance of light touch. At 6 months postoperatively, plain computed tomography scans showed bony union of the T12 vertebral body. We postulated two reasons for the absence of critical neurological dysfunction: (1) spontaneous spinal canal sparing because of the fracture of the right superior articular process in the L1 vertebral body and (2) fracture morphology, that is, a rotational fracture with mild to moderately strong shearing stress to the dura mater. J. Med. Invest. 63: 122-126, February, 2016.


Revision percutaneous endoscopic lumbar discectomy under the local anesthesia for the recurrent lumbar herniated nucleus pulposus in a high class athlete: A case Report.

Percutaneous endoscopic discectomy (PED) is a minimally invasive spinal technique and has several advantages compared with open surgery. We describe repeat PED surgery for recurrent herniated nucleus pulposus (HNP). The patient was a 33-year-old handball high level player. Previously, he underwent transforaminal PED under local anesthesia for intracanalicular HNP at L4-5 level about 2 years ago. He could return to his original competitive level. Two years later, he felt low back and right leg pain again when he was playing handball. Magnetic resonance imaging revealed the recurrence of HNP at the same level. We conducted transforaminal PED again using the exact same route as the previous surgery. Although there was a little adhesion around the L5 nerve root, we could easily identify and remove the herniated mass using endoscopic forceps. Immediately after the surgery, the low back and leg pain disappeared. Repeat PED surgery for recurrence of lumbar disc herniation is effective especially for athletes because of the benefits of PED, including surgery under local anesthesia, preservation of normal posterior structures, less postoperative pain, early discharge, and faster return to sports. J. Med. Invest. 63: 135-139, February, 2016.

The Journal of Medical Investigation : JMI


Optimizing baseplate position in reverse total shoulder arthroplasty in small-sized Japanese females: technical notes and literature review.

The management of cuff tear arthropathy (CTA) has always been a challenge for shoulder surgeons. Introduction of reverse total shoulder arthroplasty (RTSA) helped in providing pain relief and improved shoulder function in patients with CTA. In this study, we aimed to evaluate the short-term clinical results and some clinical details regarding the types of available prosthesis, positioning, and size of the components for RTSA in a population of short-stature female Japanese. In our seven cases, the average glenoid size was 23.9 mm in width and 34.2 mm in height. The average width was smaller than the size of all available baseplates. We implanted reverse shoulder prostheses with baseplate that measured 28 mm in diameter and two locking screws. The center of the baseplate was shifted to allow slight anterior overhang relative to the anatomical center to avoid breakage of the posterior cortex and to achieve firm fixation. One case of humeral shaft fracture occurred while inserting the humeral stem and required encircling wiring. In our experience, the short term clinical results of RTSA were excellent, but a new prosthesis that is designed to fit the short stature of Asians with smaller glenoid and humerus should be considered. J. Med. Invest. 63: 8-14, February, 2016.


Clinical Significance of High-intensity Zone for Discogenic Low Back Pain: A Review.

High-intensity zone (HIZ) was originally described as a high-intensity signal on T2-weighted magnetic resonance (MR) images, located in the posterior annulus fibrosus, clearly separated from the nucleus pulposus. Among symptomatic patients with low back pain, HIZ is present in 28-59% of cases. In morphologically abnormal discs, high sensitivity and specificity of 81% and 79%, respectively, were reported for HIZs and concordant pain during discography. In contrast, another report indicated low rates. Although most papers reported high sensitivity and specificity for this relationship, it remains controversial. Regarding the pathology of HIZs, inflammatory granulation tissues are found at sites showing HIZs. Such inflammatory tissues produce pro-inflammatory cytokines and mediators, which sensitize the nociceptors within the disc and cause pain. An effective treatment for this condition is yet to be established. Recently, minimally invasive surgery using percutaneous endoscopic discectomy (PED) under local anesthesia was introduced. After removal of the degenerated disc material, the HIZ is identified with the endoscope and then coagulated and modulated with a bipolar radio pulse. This technique is called thermal annuloplasty. In conclusion, HIZs is an important sign of painful intervertebral disc disruption, if identified precisely based on factors such as location and intensity. J. Med. Invest. 63: 1-7, February, 2016.


Stress fracture of the thoracic spine in an elite rhythmic gymnast: A case report.

Spondylolysis, a defect or stress fracture of the vertebral pars interarticularis, occurs most frequently in the lower lumbar spine and occasionally in the cervical spine, but is extremely rare in the thoracic spine. We report the case of a 17 year-old girl, an elite rhythmic gymnast, who reported with early-stage thoracic spondylolysis at T10 and T11 levels. Physicians should be aware that performance of unusual athletic movements, such as those by gymnasts, may lead to spondylolysis in rare locations. J. Med. Invest. 63: 119-121, February, 2016.


Hysterical conversion paralysis in an adolescent boy with lumbar spondylolysis.

We describe a case of recurrent hysterical paralysis triggered by low back pain because of lumbar spondylolysis. A 16-year-old male soccer player was referred to our institution with five previous episodes of acute paralysis triggered by severe low back pain. We performed direct surgical repair of the terminal-stage bilateral spondylolysis at L4 using a hook-rod system. His chronic low back pain was completely resolved, and no further episodes of hysterical paralysis have occurred after surgery. Spine surgeons should be aware of possible hysterical conversion paralysis when there is discrepancy between radiological and neurological findings.

Journal of Pediatric Orthopaedics. Part B


Intradural lumbar disc herniation after percutaneous endoscopic lumbar discectomy: case report.

A 64-year-old man was referred to the authors with low-back pain (LBP) and right leg pain with a history of previously diagnosed lumbar disc herniation (LDH) at L4-5. He had undergone 2 percutaneous endoscopic lumbar discectomies (PELDs) for the herniation at another institution, and according to the surgical record of the second surgery, a dural tear occurred intraoperatively but was not repaired. Postoperative conservative treatments such as an epidural block and blood patch had not relieved his persistent LBP or right leg pain. Upon referral to the authors, MRI and myelography revealed an intradural LDH. The herniated mass was removed by durotomy, and posterior lumbar interbody fusion was performed. His symptoms were partially improved after surgery. Primary suture is technically difficult when a dural tear occurs during PELD. Therefore, close attention should be paid to avoiding such tears, and surgeons should increase their awareness of intradural LDH as a possible postoperative complication of PELD.


Percutaneous Endoscopic Discectomy via Transforaminal Route for Discal Cyst.

Background. Discal cyst has been identified as a rare cause of low back pain and radiating leg pain. The pathogenesis and management of this condition are still debated. The largest number of reported cases had undergone microsurgery while very few cases have been treated with percutaneous endoscopic discectomy (PED). Methods. An 18-year-old boy complained of low back pain radiating to right leg after a minor road traffic accident. Diagnosis of a discal cyst at L4-L5 level was made based on magnetic resonance imaging (MRI). Despite conservative management for 6 months, the low back pain and radiating leg pain persisted so surgical treatment by PED was performed under local anesthesia. As the patient was a very active baseball player, his physician recommended a minimally invasive procedure to avoid damage to the back muscles. Results. The patient's low back pain and leg pain disappeared immediately after surgery and he made a rapid recovery. He resumed mild exercise and sports practice 4 weeks after surgery. Complete regression of the cystic lesion was demonstrated on the 2-month postoperative MRI. Conclusion. A minimal invasive procedure like PED can be an effective surgical treatment for discal cyst, especially in active individuals who play sports.


Consecutive assessment of FA and ADC values of normal lumbar nerve roots from the junction of the dura mater.

Our study demonstrated that ADC and FA values of each L4, 5, and S1 at the proximal portion from the junction of the dura matter changed linearly. It would be useful to know the normal profile of DTI values by location of each nerve root so that we can detect subtle abnormalities in each nerve root.

ADC values of all L4, 5, and S1 nerve roots decreased linearly up to 15 mm from the dura junction and was constant distally afterward. ADC values in the proximal portion demonstrated S1 > L5 > L4 (p < 0.05). On the other hand, FA values increased linearly up to 15 mm from the dura junction, and was constant distally afterward. FA values in the proximal portion showed L4 > L5 > S1 (p < 0.05).


Tenosynovial Giant Cell Tumor, Diffuse Type/Pigmented Villonodular Synovitis in a Pars Defect: A Case Report.


A review of the pathomechanism of forward slippage in pediatric spondylolysis : The Tokushima theory of growth plate slippage

Spondylolysis is a stress fracture of the pars interarticularis, which in some cases progresses to spondylolisthesis (forward slippage of the vertebral body). This slip progression is prevalent in children and occurs very rarely after spinal maturation. The pathomechanism and predilection for children remains controversial despite considerable clinical and basic research into the disorder over the last three decades. Here we review the pathomechanism of spondylolytic spondylolisthesis in children and adolescents, and specifically the Tokushima theory of growth plate slippage developed from our extensive research findings. Clinically, we have observed the slippage site near the growth plate on MRI; then, using fresh cadaveric spines, we found the weakest link against forward shear loading was the growth plate. We subsequently developed an immature rat model showing forward slippage after growth plate injury. Moreover, finite element analysis of the pediatric spine clearly showed increased mechanical stress at the growth plate in the spondylolytic pediatric spine model compared with the intact pediatric spine. Thus, spondylolysis progresses to spondylolisthesis (forward slippage) in children and adolescents with the growth plate as the site of the slippage. Repetitive mechanical loading on to the growth plate may serve to separate the growth plate and subsequently progress to spondylolisthesis.

The Journal of Medical Investigation : JMI


Percutaneous Endoscopic Lumbar Discectomy for a Huge Herniated Disc Causing Acute Cauda Equina Syndrome : A Case Report

Microsurgery for lumbar disc herniation that requires surgical intervention has been well described. The methods vary from traditional open discectomy to minimally invasive techniques. All need adequate preanesthetic preparation of patients as general anesthesia is required for the procedure, and nerve monitoring is necessary to prevent iatrogenic nerve injury. Conventional surgical techniques sometimes require the removal of the corresponding lamina to assess the nerve root and herniated disc, and this may increase the risk for posterior instability of the vertebral body. Should this occur, fusion surgery may be needed, further increasing morbidity and cost. We present here a case of lumbar herniated disc fragments causing acute cauda equina syndrome that were endoscopically resected through a transforaminal approach in an awake patient under local anesthesia. Percutaneous endoscopic discectomy under local anesthesia proved to be a better alternative to open back surgery as it made immediate intervention possible, was associated with fewer perioperative complications and morbidity, minimized soft tissue damage, and allowed early rehabilitation with a better outcome and greater patient satisfaction. In addition to these advantages, percutaneous endoscopic discectomy protects other approaches that may be needed in subsequent surgeries, whether open or minimally invasive.


Local administration of zoledronic Acid for giant cell tumor of bone.

Giant cell tumor of bone is a locally aggressive tumor with a high local recurrence rate. Several adjuvant therapies have been employed to reduce the recurrence rate, but their effectiveness remains controversial. The authors attempted local administration of zoledronic acid, a nitrogen-containing bisphosphonate that strongly inhibits bone resorption, as an adjuvant treatment for histologically proven giant cell tumor of bone in 5 patients at their institution. After biopsy, 4 patients were treated with local administration of zoledronic acid with artificial bone and 1 was treated with zoledronic acid without artificial bone. Histologic response to the treatment was evaluated with surgically resected specimens. The 4 patients treated with artificial bone showed local control, with histologic tumor necrosis rates of 90%, 90%, 50%, and 10%. Magnetic resonance imaging showed poor gadolinium enhancement, and histologic examination after local zoledronic acid treatment showed tumor necrosis. One patient without artificial bone showed no histologic tumor necrosis and had local recurrence in soft tissue 18 months after tumor resection. A 3-week waiting period between biopsy and zoledronic acid treatment appears reasonable from the histological study. Complication of this therapy was delayed wound healing and it occurred in 2 cases. Taken together, this case series suggests that local administration of zoledronic acid with artificial bone is a potential adjuvant therapy for giant cell tumor of bone. On the other hand, effective local administration of zoledronic acid requires some bone matrix, including artificial bone. Campanacci's grading is important for predicting the effect of local administration of zoledronic acid. [Orthopedics. 2015; 38(1):e25-e30.].


State-of-the-art ultrasonographic findings in lower extremity sports injuries.

Athletes sometimes experience overuse injuries. To diagnose these injuries, ultrasonography is often more useful than plain radiography, computed tomography (CT), or magnetic resonance imaging (MRI). Ultrasonography can show both bone and soft tissue from various angles as needed, providing great detail in many cases. In conditions such as osteochondrosis or enthesopathies such as Osgood-Schlatter disease, Sinding-Larsen-Johansson disease, bipartite patella, osteochondritis dissecans of the knee, painful accessory navicular,and jumper's knee, ultrasonography can reveal certain types of bony irregularities or neovascularization of the surrounding tissue. In patients of enthesopathy, ultrasonography can show the degenerative changes at the insertion of the tendon. Given its usefulness in treatment, ultrasonography is expected to become essential in the management of overuse injuries affecting the lower limb in athletes. J. Med. Invest. 62: 109-113, August, 2015.


Foraminoplastic transforaminal percutaneous endoscopic discectomy at the lumbosacral junction under local anesthesia in an elite rugby player.

Percutaneous endoscopic discectomy (PED) is the least invasive disc surgery available at present. The procedure can be performed under local anesthesia and requires only an 8 mm skin incision. Furthermore, damage to the back muscle is considered minimal, which is particularly important for disc surgery in athletes. However, employing the transforaminal (TF) PED approach at the lumbosacral junction can be challenging due to anatomical constraints imposed by the iliac crest. In such cases, foraminoplasty is required in addition to the standard TF procedure. A 28-year-old man who was a very active rugby player visited us complaining of lower back and left leg pain. His visual analog scale (VAS) score for pain was 8/10 and 3/10, respectively. MRI revealed a herniated nucleus pulposus at L5-S level. TF-PED was planned; however, the anatomy of the iliac crest was later found to prevent access to the herniated mass. Foraminoplasty was therefore performed to enlarge the foramen, thereby allowing a cannula to be passed through the foramen into the canal without causing exiting nerve injury. The herniated mass was then successfully removed via the TF-PED procedure. Pain resolved after surgery, and his VAS score decreased to 0/10 for both back and leg pain. The patient returned to full rugby activity 8 weeks after surgery. In conclusion, even with an intracanalicular herniated mass at the lumbosacral junction, a TF-PED procedure is possible if additional foraminoplasty is adequately performed to enlarge the foramen. J. Med. Invest. 62: 238-241, August, 2015.


State of the art: Intraoperative neuromonitoring in spinal deformity surgery.

Application of deformity correction spinal surgery has increased substantially over the past three decades in parallel with improvements in surgical techniques. Intraoperative neuromonitoring (IOM) techniques,including somatosensory evoked potentials (SEPs), muscle evoked potentials (MEPs), and spontaneous electromyography (free-run EMG), have also improved surgical outcome by reducing the risk of iatrogenic neural injury. In this article, we review IOM techniques and their applications in spinal deformity surgery. We also summarize results of selected studies including hundreds of spinal correction surgeries. These studies indicate that multimodal IOM of both motor and sensory responses is superior to either modality alone for reducing the incidence of neural injury during surgery. J. Med. Invest. 62: 103-108, August, 2015.


Recurrence of type I Modic inflammatory changes in the lumbar spine: effectiveness of intradiscal therapy.

Here we report a case of recurrence of Modic type I inflammatory changes in the lumbar spine. A 49-year-old man was referred to our department with a history of chronic low back pain of at least 20 years. At the first consultation, he complained of low back pain only and had no other symptoms such as leg pain, numbness, or weakness. Although his pain was typically mild, he experienced one or two episodes of severe and incapacitating low back pain a year. After two intradiscal steroid injections, his pain disappeared immediately and completely. After 6 months of conservative treatment, Modic type I change switched to Modic type II change. However, 12 months after the first treatment, he once again experienced severe low back pain. Follow-up magnetic resonance imaging (MRI) indicated recurrence of Modic type I change that was stronger than the first occurrence. Two intradiscal injections relieved the pain. Six months after the second episode, follow-up MRI showed another switch of Modic type I change to Modic type II change. Switches of Modic change have been controversial, with mixed findings on pain, natural history, and degenerative changes. The present case reinforces the notion that Modic type I change corresponds to reversible local inflammation.


Complete resolution of a case of calcific tendinitis of the longus colli with conservative treatment.

Acute calcific tendinitis of the longuscolli is a self-limiting inflammatory condition caused by calcium hydroxyapatite deposition in the longuscolli tendon. Although several case reports have described its radiological presentation, few reports provide detailed chronological accounts through symptomatic and radiologic resolution. A 59-year-old woman presented with severe neck pain and stiffness of a few days duration as well as moderate discomfort when swallowing. Lateral radiographs revealed a large calcium deposit anterior to the C1.C2 joint and swelling of the prevertebral soft tissue from C1 to C5. CT and magnetic resonance imaging showed fluid in the retropharyngeal gap.A soft collar and non-steroidal anti-inflammatory drug were prescribed, without antibiotics. At 4 months after presentation, the calcium deposit and all symptoms had resolved completely. Although this disease is comparatively rare, physicians should keep it in mind when a patient presents with acute severe neck pain.


Analysis of MRI signal changes in the adjacent pedicle of adolescent patients with fresh lumbar spondylolysis.

MRI revealed a higher prevalence of L3 or L4 spondylolysis than observed with CT.

MRI signal changes were detected in 150 adjacent pedicles of 101 vertebrae. Of these vertebrae, MRI signal changes in only 67 (66.3 %) corresponded to L5, while changes in 34 (33.7 %) corresponded to L3 or L4. In our follow-up study, the bone-healing rate with no vertebral defect was 100 % at L3, 97.1 % at L4, and 84.4 % at L5. In addition, 11 of 34 (32.4 %) vertebrae with signal changes at L3 or L4 occurred with L5 terminal-stage spondylolysis (no MRI signal change).


Minimally Invasive Microendoscopic Resection of the Transverse Process for Treatment of Low Back Pain with Bertolotti's Syndrome.

Bertolotti's syndrome is characterized by anomalous enlargement of the transverse process of the most caudal lumbar segment, causing chronic and persistent low back pain or sciatica. We describe the case of a 45-year-old woman who presented with left sciatic pain and low back pain due to a recurrent lumbar disc herniation at L4-5 with Bertolotti's syndrome. Selective L5 nerve root block and local injection of lidocaine into the articulation between the transverse process and sacral ala temporarily relieved the left sciatic pain and low back pain, respectively. To confirm the effect of local injection on low back pain, we gave a second local injection, which once again relieved the low back pain. Microendoscopic resection of the pseudoarticulation region and discectomy successfully relieved all symptoms. This report illustrates the effectiveness of minimally invasive resection of the transverse process for the treatment of low back pain with Bertolotti's syndrome.


Intradural extramedullary capillary hemangioma in the upper thoracic spine: a review of the literature.

Capillary hemangiomas are benign tumors found in the skin and soft tissues in younger people. They occur in the central nervous system only rarely, and intradural occurrence is extremely rare. We report here a 60-year-old man presenting with thoracic girdle pain and progressive gait disturbance. Magnetic resonance images of the thoracic spine showed a 12 × 8 × 20 mm, well-defined intradural mass at the T2 level, compressing the spinal cord laterally. Relative to the spinal cord, the mass was hypo- to isointense on T1-weighted images and relatively hyperintense on T2-weighted images, with strong enhancement on contrast-enhanced T1-weighted images. The patient underwent T1-2 hemilaminectomy with resection of the intradural extramedullary tumor, which showed characteristics of a capillary hemangioma on histologic examination. The patient's symptoms improved following the surgery and no clinical or radiological evidence of recurrence was noted at the 2-year follow-up. We present this case with a review of the literature, highlighting features for differential diagnosis.


Discoscopic findings of high signal intensity zones on magnetic resonance imaging of lumbar intervertebral discs.

A 32-year-old man underwent radiofrequency thermal annuloplasty (TA) with percutaneous endoscopic discectomy (PED) under local anesthesia for chronic low back pain. His diagnosis was discogenic pain with a high signal intensity zone (HIZ) in the posterior corner of the L4-5 disc. Flexion pain was sporadic, and steroid injection was given twice for severe pain. After the third episode of strong pain, PED and TA were conducted. The discoscope was inserted into the posterior annulus and revealed a migrated white nucleus pulposus which was stained blue. Then, after moving the discoscope to the site of the HIZ, a migrated slightly red nucleus pulposus was found, suggesting inflammation and/or new vessels penetrating the mass. After removing the fragment, the HIZ site was ablated by TA. To our knowledge, this is the first report of the discoscopic findings of HIZ of the lumbar intervertebral disc.


Magnetic resonance imaging in adolescent symptomatic navicular tuberosity.

The accessory navicular bone is one of the most common accessory ossicles, which sometimes become symptomatic. Abnormalities in magnetic resonance (MR) image, e. g. edema-like bone marrow pattern, have been reported for symptomatic accessory navicular. However, it has not been completely understood the edema-like bone marrow pattern correlates to the symptom of navicular tuberosity. We investigated the edema-like bone marrow pattern in correlation with alleviation of the symptom and the presence of accessory navicular bone. Ten adolescents with pain localized to the navicular tuberosity were recruited and seven cases were further examined with consecutive MR images. Edema-like bone marrow pattern was found in all symptomatic navicular but not in asymptomatic navicular. Intensity of the pattern diminished with alleviation of the symptom. Moreover, this correlation was recognized even in the patients who had no accessory navicular bones. MR images could be used not only for diagnosis but for monitor of healing in adolescent symptomatic navicular. There may be different pathologic mechanism for adolescent symptomatic navicular tuberosity, such as an osteitis, in adolescents.

The Journal of Medical Investigation : JMI


Diffusion-weighted imaging and diffusion tensor imaging of asymptomatic lumbar disc herniation.

Diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) were performed on a healthy 31-year-old man with asymptomatic lumbar disc herniation. Although the left S1 nerve root was obviously entrapped by a herniated mass, neither DWI nor DTI showed any significant findings for the nerve root. Decreased apparent diffusion coefficient (ADC) values and increased fractional anisotropy (FA) values were found. These results are contrary to those in previously published studies of symptomatic patients, in which a combination of increased ADC and decreased FA seem to have a relationship with nerve injury and subsequent symptoms, such as leg pain or palsy. Our results seen in an asymptomatic subject suggest that the compressed nerve with no injury, such as edema, demyelination, or persistent axonal injury, may be indicated by a combination of decreased ADC and increased FA. ADC and FA could therefore be potential tools to elucidate the pathomechanism of radiculopathy.


Clinical Outcome of Minimally Invasive Repair of Pars Defect Using Percutaneous Pedicle Screws and Hook-Rod System in Adults with Lumbar Spondylolysis.


Multi-level spondylolisthesis required transdiscal screws due to the rare vertebral deformities.A case report.


Late-onset Non-dysraphic Intradural Spinal Cord Lipoma: A Case Report and Literature Review.


State of the Art: Transforaminal Approach for Percutaneous Endoscopic Lumbar Discectomy under Local Anesthesia.

Minimally invasive percutaneous endoscopic discectomy (PED) with a transforaminal approach under local anesthesia was started in the late 20th century. As the procedure requires a skin incision of only 8 mm, it is the least invasive disc surgery procedure at present, and owing to advances in instruments and optics, the use of this technique has gradually spread. In Japan, Dr. Dezawa from Teikyo University Mizonokuchi Hospital introduced this technique in 2003. Thanks to his efforts, the number of surgeons who can perform PED has increased, although the number of active PED surgeons is still only around 20. The first author (K.S.) started PED in 2010. In this review article, we explain the state-of-the-art PED transforaminal technique for minimally invasive disc surgery and present three successful cases. J. Med. Invest. 61: 217-225, August, 2014.


The state of the art in arthroscopic hip surgery.

Hip arthroscopy is among the most rapidly evolving arthroscopic techniques in the last decade and offers the benefits of being both a minimally invasive procedure and an excellent diagnostic tool. Improvements in instrumentation and surgical skills have advanced our ability to accurately diagnose and treat various conditions of the hip joint, and hip arthroscopy has elucidated several pathologies that cause disabling symptoms. Many of these conditions were previously unrecognized and left untreated. The indications for hip arthroscopy include the management of early osteoarthritis, synovial disorders (e. g., synovial osteochondromatosis), labral tears, chondral lesions, and femoroacetabular impingement (FAI), which is increasingly recognized as a disorder that can lead to the development of early cartilage and labral injury. A better understanding of hip arthroscopy, including the anatomy, improved surgical techniques, indications, and complications of the procedure, is essential for its success. This review article discusses the state of the art of arthroscopic hip surgery. J. Med. Invest. 61: 226-232, August, 2014.


State of the art: elbow arthroscopy: review of the literature and application for osteochondritis dissecans of the capitellum.

Elbow arthroscopy has become a safe and effective treatment option for a number of elbow disorders. The most rewarding and successful indication is the removal of loose bodies. Loose bodies are often a result of osteochondritis dissecans (OCD) of the capitellum, and arthroscopy in this case is useful for performing debridement, thereby eliminating the need for a more extensive open procedure associated with complications. In this review, we describe our arthroscopic technique for OCD of the capitellum. We usually conduct arthroscopy in the supine position, and use 2.9-mm arthroscopes of 30° and 70°. The 70° arthroscope provides a greater operative field than the 30° arthroscope. Arthroscopic treatment for OCD may require 2 anterior and 2 posterior portals. Loose bodies are commonly found in the radial fossa, coronoid fossa, and in the olecranon fossa. Once the loose bodies are removed, all unstable cartilage of the capitellum lesion is removed to create a stable bed. If any sclerotic changes to the lesion bed are observed, we create microfractures in the lesion bed. The most significant complication in arthroplasty is neurovascular injury. However, we have never experienced this devastating complication, which can be avoided by paying careful attention to detail. J. Med. Invest. 61: 233-240, August, 2014.


Surgery Related Complications in Percutaneous Endoscopic Lumbar Discectomy under Local Anesthesia.

The minimally invasive percutaneous endoscopic discectomy (PED) as the postero-lateral approach with the local anesthesia was started in the late 20th century. The procedure only requires 8 mm of skin incision; thus, it is the least invasive disc surgery presently. The surgery related complications were reviewed in the initial 100 cases from the single surgeon (K. S., first author). Two cases showed exiting nerve irritation, and complained of leg paresthetic pain for 6 to 12 weeks after the surgery (2.0%). The symptoms got better with medicines. One showed post-surgical epidural hematoma, and required surgical removal of the mass (1.0%). Two cases complained neck pain during surgery (2.0%). Surgeons would be aware of the specific complications for the postero-lateral approach of PED procedure. J. Med. Invest. 61: 264-269, August, 2014.


Hybrid technique of cortical bone trajectory and pedicle screwing for minimally invasive spine reconstruction surgery: A technical note.

The pedicle screw (PS) system is widely used for spinal reconstruction. Recently, screw insertion using the cortical bone trajectory (CBT) technique has been reported to provide increased holding strength of the vertebra, even in an osteoporotic spine. CBT is also beneficial due to its low invasiveness. We have been performing hybrid reconstruction with CBT at the cranial level and PS at the caudal level based on the concept of minimal invasiveness. We applied this hybrid technique to 6 cases of degenerative spondylolisthesis. Surgery was completed with a small skin incision of around 5-6 cm, which is shorter than that of the conventional PS procedure. The mean percent slippage before surgery was 19.8%, and this was reduced to 3.9% after surgery and almost maintained 3 months after surgery. Furthermore, no major surgical complications were observed. Here, we introduce the minimally invasive hybrid technique of CBT-PS. Surgeons should be aware of the procedure as an option for minimally invasive lumbar spine reconstructive surgery. J. Med. Invest. 61: 388-392, August, 2014.


Reconstruction of chronic Achilles tendon rupture using the semitendinosus tendon: a case report.

Achilles tendon rupture is a common trauma requiring surgical management. For chronic Achilles tendon rupture in particular, reconstructive surgery is desirable and several methods have been described. Here we present a case of chronic Achilles tendon rupture reconstructed using the semitendinosus tendon because of the difficulty in pulling down the proximal stump to reach the distal stump and due to an insufficient margin for hooking a suture to the distal stump. Postoperatively, the patient had a fully functional tendon and resumed his normal activities of daily living. Using this surgical technique, we expect favorable outcomes in cases of Achilles tendon rupture. J. Med. Invest. 61: 417-420, August, 2014.

The Journal of Medical Investigation : JMI


Spontaneous rupture and hemorrhage of myxopapillary ependymoma of the filum terminale: a case report and literature review.

We present a rare case of acute onset cauda equina syndrome caused by a ruptured myxopapillary ependymoma with accompanying hemorrhage. A 26-year-old healthy woman developed muscle weakness and sensory disturbances in her bilateral lower extremities. Magnetic resonance imaging showed a huge mass from the L1 body to the L2-3 disc level. She was able to ambulate with crutches after the tumor was successfully removed. To prevent recurrence, she received whole brain and spinal cord radiation. No sing of recurrence were detected at the 8 month follow up. J. Med. Invest. 61: 430-435, August, 2014.


Efficacy of hip arthroscopy in the diagnosis and treatment of synovial osteochondromatosis: a case report and literature review.

Here we report a rare case of synovial osteochondromatosis of the hip and provide a brief review of the literature. A 37-year-old woman was referred to our department with a 3-year history of right hip pain. At initial consultation, she complained of pain upon standing and when sitting down, occasional pain at rest and nocturnal pain in the right hip, and worsening of the pain at premenstruum. The range of motion of the affected hip was totally limited by pain. Plain radiography revealed a slightly calcified (or ossified) lesion at the acetabular fossa of the right hip. Computed tomography showed clusters of loose bodies filling the acetabular fossa. Synovial osteochondromatosis was suspected and she underwent hip arthroscopic surgery. Complete resection was performed using the lateral and anterior portals. Postoperatively, her symptoms disappeared entirely and she was discharged 4 days after surgery. The patient regained full range of motion of the right hip and follow-up CT revealed no remaining loose bodies in the right hip. Hip arthroscopy is considered to be effective for the diagnosis and treatment of synovial osteochondromatosis of the hip and is minimally invasive. J. Med. Invest. 61: 436-441, August, 2014.


Persistent tight hamstrings following conservative treatment for apophyseal ring fracture in adolescent athletes: critical appraisal.

Apophyseal ring fracture is a unique disease in children and adolescents. Its clinical features include low back pain, sciatica, paravertebral muscle spasm and tenderness, restricted back motion, neurological symptoms, and tight hamstrings. For all athletes, body flexibility is one of the most important factors for better performance. Therefore, persistent tight hamstrings has a negative influence on athletic performance. In this report, we present two adolescent athletes with apophyseal ring fracture treated successfully by conservative treatment for severe low back pain (LBP) and leg pain, despite having persistent tight hamstrings for more than one year. Unlike herniated nucleus pulposus, bony fragments in the spinal canal never disappear. Although conservative treatment can alleviate LBP and leg pain, surgical removal of fragments is considered when symptoms such as tight hamstrings and restricted lumbar motion due to canal stenosis are found, particularly in athletes. J. Med. Invest. 61: 446-451, August, 2014.


Endoscope Assisted Excision of a Juxtafacet Cyst in an Adolescent Athlete: A Case Report.

Juxtafacet cysts (JFCs) are a cause of back and radicular pain that can be treated conservatively and operatively. Such strategies include lumbosacral brace, epidural injection, open surgery, and minimally invasive surgery; although surgical treatment is usually reserved for unsuccessful conservative treatment. The role of minimally invasive surgery in athletic youth with JFCs has yet to be determined. The patient is a 16-year-old basketball player with a JFC. We performed endoscope-assisted cystectomy. Endoscope-assisted JFC excision immediately and completely resolved the patient's lower back and leg pain with no recurrence of symptoms 4 years after surgery. We suggest that JFCs of the lumbar spine be a part of the differential diagnosis in young patients with back and radicular pain. Furthermore, we recommend that endoscope-assisted surgery be employed in the treatment of JFCs in young athletes.

Journal of Neurological Surgery. Part A, Central European Neurosurgery


Comparison between high-resolution isotropic three-dimensional and high-resolution conventional two-dimensional FSE MR images of the wrist at 3 tesla: a pilot study.

With regard to clinical applications, 3D MRI of the wrist has almost equal potential to 2D MRI.

The 2D MRI demonstrated significantly higher scores than 3D in anatomic delineation of the SL ligament (P = 0.013), fat suppression (P = 0.013), and image blur (P = 0.003). The remaining quantitative analyses, including overall quality, revealed no statistical significances between 2D and 3D MRI. There were no statistical differences in relative SI of each structure between 2D and 3D imaging, except for bone marrow with fat suppression. There were no significant differences in relative fluid to TFCC and fluid to bone marrow contrast between 2D and 3D imaging, suggesting that both sequences have similar rates of detection for TFCC pathology and bone marrow lesions.

Journal of Magnetic Resonance Imaging : JMRI


Quantitative measurement of femoral condyle cartilage in the knee by MRI: validation study by multireaders.

Inter- and intraobserver reproducibility of cartilage segmentation using semiautomated software was validated. Although there was no statistical significance, there was a tendency of under- or overestimating CV by each sequence.


Percutaneous Endoscopic Lumbar Discectomy for Athletes


Lumbar spondylolysis in juveniles from the same family: a report of three cases and a review of the literature.

Spondylolysis is reported as a stress fracture of the pars interarticularis with a strong hereditary basis. Three cases of lumbar spondylolysis in juveniles from the same family are reported, and the genetics of the condition are reviewed. The first boy, a 13-year-old soccer player, was diagnosed with terminal stage L5 bilateral spondylolysis with grade 1 slippage. The second boy, a 10-year-old baseball player, had terminal stage right side unilateral spondylolysis. The third boy, also a 10-year-old baseball player, was diagnosed with early stage bilateral L5 spondylolysis. The second and third boys are identical twins, and all three cases exhibited concomitant spina bifida occulta. Lumbar spondylolysis has a strong hereditary basis and is reported to be an autosomal dominant condition.


Jack-knife stretching promotes flexibility of tight hamstrings after 4 weeks: a pilot study.

Tight hamstrings are reported to be one of the causes of low back pain. However, there have been few reports on effective stretching procedures for the tight hamstrings. The so-called jack-knife stretch, an active-static type of stretching, can efficiently increase the flexibility of tight hamstrings. To evaluate hamstring tightness before and after the 4-week stretching protocol in healthy volunteer adults and patients aged under 18 years with low back pain. For understanding the hamstrings tightness, we measured two parameters including (1) finger to floor distance (FFD) and (2) pelvis forward inclination angle (PFIA). Eight healthy adult volunteers who had no lumbar or hip problems participated in this study (mean age: 26.8 years). All lacked flexibility and their FFD were positive before the experiment. Subjects performed 2 sets of the jack-knife stretch every day for 4 weeks. One set consisted of 5 repetitions, each held for 5 s. Before and during the 4-week experiment, the FFD and PFIA of toe-touching tests were measured weekly. For 17 of the sports players aged under 18, only FFD was measured. In adult volunteers, FFD was 14.1 ± 6.1 cm before the experiment and decreased to -8.1 ± 3.7 cm by the end of week 4, indicating a gain in flexibility of 22.2 cm. PFIA was 50.6 ± 8.2 before the experiment and 83.8 ± 5.8 degrees after. Before and after the experiment, the differences were significant (p < 0.05). For those aged under 18, FFD was 8.1 ± 8.0 and -9.6 ± 6.8, before and after the stretching, respectively. This difference was significant (p < 0.05). The jack-knife stretch is a useful active-static stretching technique to efficiently increase flexibility of tight hamstrings.

European Journal of Orthopaedic Surgery & Traumatology


Clinical outcomes of spinal surgery in patients treated with hemodialysis.

Even in patients treated with long-term HD, spinal surgeries reliably obtain neurological and functional improvement if surgeons judge the preoperative inclusion criteria correctly. However, if surgeries are necessary for these patients, surgeons should consider the patients' comorbidity-related survival rate after the spinal surgeries.

Journal of Spinal Disorders & Techniques


Synchronic multiple stress fractures of L5 left hemilamina:a case of an unusual type of lumbar spondylolysis


Two types of laminolysis in adolescent athletes.

Bony defects in the spine are divided into three main types: spondylolysis, pediculolysis, and laminolysis. Lumbar spondylolysis is a well-known stress fracture that occurs frequently in adolescent athletes. Pediculolysis means stress fracture of the pedicle, which sometimes occurs subsequent to unilateral spondylolysis. Laminolysis is a rarely reported stress fracture similar to spondylolysis and pediculolysis that sometimes causes low back pain (LBP). However, its pathomechanism has not been elucidated. Recently, we encountered four adolescent athletes with symptomatic laminolysis. Mean age was 15.8 (range 15-17) years. All subjects reported severe LBP exacerbated by extension of the lumbar spine, and radiology revealed two types of laminolysis: hemilaminar type and intralaminar type. To elucidate the mechanisms of each type, we reviewed a biomechanical study, and found that the hemilaminar type was thought to be subsequent to contralateral spondylolysis, while the intralaminar type might be a result of a stress fracture due to repetitive extension loading.

Journal of Orthopaedics and Traumatology


Flavokawain B, a novel, naturally occurring chalcone, exhibits robust apoptotic effects and induces G2/M arrest of a uterine leiomyosarcoma cell line.

To examine the effects of flavokawain B (FKB), a novel kava chalcone, on the growth of uterine leiomyosarcoma (LMS) cells and investigated its utility in the treatment of uterine LMS. Uterine leiomyosarcoma (SK-LMS-1), endometrial adenocarcinoma (ECC-1) and the non-malignant, human endometrium fibroblast-like (T-HESC) cell lines were cultured and treated with different concentrations of FKB. Cell viability was determined by MTT assays and the IC(50) was estimated. Fluorescent-activated cell sorting (FACS) analysis of apoptosis and cell cycle was performed. Real-time reverse-transcription polymerase chain reaction and western blot analysis were utilized to evaluate differences in the expression of apoptotic markers. FKB preferentially inhibited the growth of SK-LMS-1 and ECC-1 cells compared to T-HESC control cells. FKB significantly increased both early and late apoptosis in SK-LMS-1 and ECC-1 cells relative to control. Cell cycle analysis illustrated an increase in the G2/M fraction in treated cell lines relative to control. Furthermore, FKB induced the expression of pro-apoptotic death receptor 5 (DR5), Bim, and Puma, and decreased expression of an inhibitor of apoptosis, survivin. FKB also acted synergistically when combined with docetaxel and gemcitabine (combination index = 0.260). FKB treatment results in cell cycle arrest and a robust induction of apoptosis in SK-LMS-1 and ECC-1 cell lines. This natural product deserved further investigation as a potential therapeutic agent in the treatment of uterine LMS.

The Journal of Obstetrics and Gynaecology Research


Conservative treatment for pediatric lumbar spondylolysis to achieve bone healing using a hard brace: what type and how long?

Various kinds of trunk braces have been used to achieve bone healing in cases of pediatric lumbar spondylolysis. However, the optimal brace for achieving bone healing is unclear. The purpose of the present study was to determine in what types of spondylolysis bone healing can be achieved and how long it takes. In this prospective study, 63 pars interarticularis defects (spondylolysis) among 37 patients who were younger than 18 years (mean 13.5 ± 2.7 years) were treated using a hard brace. The youngest patient was 8 years old. Based on the results of CT scanning, the lyses were classified into 3 categories: early, progressive, and terminal defects. Progressive defects were further divided into 2 types according to STIR MRI findings: those with high signal intensity at the adjacent pedicle and those with low signal intensity (that is, a normal appearance). A hard brace, such as a molded plastic thoracolumbosacral orthosis, was used to immobilize the trunk. Approximately every 3 months, CT scanning was performed to evaluate bone healing until approximately 6 months. The union rates were 94%, 64%, 27%, and 0% for the early, progressive with high signal intensity, progressive with low signal intensity, and terminal defects, respectively. It was noted that no terminal defect was healed using conservative treatment. The mean time to healing among the defects that showed bone healing was 3.2, 5.4, and 5.7 months for the early, progressive with high signal intensity, and progressive with low signal intensity groups, respectively. Patients with early-stage defects are the best candidates for conservative treatment with a hard brace because more than 90% of such cases can be healed in 3 months.


MRI Changes of the Spinal Subdural Space after Lumbar Spine Surgeries: Report of Two Cases.

Although magnetic resonance imaging (MRI) is frequently used to assess the lumbar spine, there are few reports in the medical literature that have evaluated using MRI immediately following spinal surgery. Furthermore, descriptions of the subdural changes after lumbar spine surgery are also infrequent. In this paper, we present two cases with subdural change seen on MRI immediately after lumbar surgery. Both the patients had mild symptoms that resolved spontaneously, and the follow-up MRI scans showed resolution of the subdural changes. Subdural changes should be considered as one of the possible causes of unexpected symptoms in patients following lumbar spinal surgery.


Retrospective Study of Deep Surgical Site Infections Following Spinal Surgery and the Effectiveness of Continuous Irrigation.

Surgical site infection (SSI) is an unfortunate and unpreventable complication of any surgical intervention including spinal surgery. Early deep SSI (EDSSI) after instrumented spinal fusion are particularly difficult to manage due to the implanted, and possibly infected, instrumentation. The purpose of this study is to retrospectively review patients who underwent spinal surgery, investigate the rate of EDSSI, identify patient-related and surgery-related risk factors and to assess the effectiveness of continuous indwelling irrigation on the eradication of these infections. A total of 814 patients (319 women and 495 men) who underwent spinal surgery were enrolled. Mean age at the initial surgery was 57.4 years old. Infections that penetrated the deep fascia within 1 month after the initial operation were considered as EDSSI. The rate of EDSSI, causal organisms, infection management and resolution were studied. Furthermore, we examined the patient-related and the operation-related risk factors. An overall incidence of EDSSI of 1.1% was found. In 177 patients with diabetes mellitus (DM), two patients (1.1%) developed EDSSI. In 28 patients receiving chronic haemodialysis (HD), two patients with infections (7.1%) were identified, which was statistically significantly greater than the other patient populations. Both operative time and intraoperative blood loss were significantly greater in patients with EDSSI than in non-infected patients. Furthermore, the rate of EDSSI in patients undergoing instrumented spinal fusion (3.8%) was significantly higher than that in the other patients. In the nine patients who developed EDSSI, the causal organisms were identified and treated by surgical debridement, antibiotic therapy and continuous indwelling surgical site irrigation. All infections resolved, and no recurrence has been observed at final follow-up. Removal of the instrumentation was required in only one patient. Based on our results, we believe that continuous surgical site irrigation is an effective adjunct in the surgical treatment for early SSI following spinal surgery.


A remarkable case of hypertrophic pseudoarthrosis of the pars interarticularis in a young American football professional player.

Lumbar spondylolysis is a defect of the pars interarticularis regarded as a stress fracture. The bone stump around the pars defect usually appears atrophic and is fibrously united or filled with fibro cartilaginous mass, similar to long bone pseudoarthrosis. Lumbar spondylolysis sometimes causes bone growth resembling that of an osteophyte in osteoarthritis, and in elderly patients, the ragged edges result in radiculopathy around the defect. However, lumbar spondylolysis is rarely reported to cause hypertrophic changes resulting in spinal canal stenosis in young patients. In this report, we present an unprecedented radiological finding of distinctive hypertrophic change around the pars defect, which occurred in a young professional football player.

European Journal of Orthopaedic Surgery & Traumatology


Hemorrhagic Facet Cyst in the Lumbar Spine Causing Contralateral Leg Symptoms: A Case Report

Here we present a case of hemorrhagic lumbar facet cyst presenting with progressive radiculopathy only on the contralateral side. If a patient has previous back pain or neuropathy for several months and then suddenly deteriorates, hemorrhagic facet cyst of the lumbar spine should be part of the differential diagnosis. However, as in the present case, we should be aware that there is a possibility of a contralateral lesion.


Painful lumbar spondylolysis among pediatric sports players: a pilot MRI study.

For children and adolescents who are very active athletes, fresh lumbar spondylolysis is the main pathologic cause of lower back pain (LBP). However, regarding the terminal-stage spondylolysis (pars defect), there have been few studies to clarify the pathomechanism of LBP. The purpose of this study is to clarify the cause of LBP associated with pars defects in athletes. This is the first report showing a possible pathomechanism of LBP in active athletes with painful pars defect. Six pediatric athletes (5 boys and 1 girl) below 18 years old with painful bilateral lumbar spondylolysis were evaluated. In all cases, spondylolysis was identified as terminal stage (pseudoarthrosis) on CT scan. To evaluate the inflammation around the pars defects, short time inversion recovery (STIR) MRI was performed along with the sagittal section. Fluid collection, which is an indicator of inflammatory events, was evaluated in 12 pars defects as well as in 12 cranial and caudal adjoining facet joints. Inflammation (i.e., fluid collection) was observed in all 12 pars defects in six subjects at the pseudoarthrotic pars defects. In terms of facet joints, 7 of 12 (58%) pars defects showed fluid collection at the cranial and/or caudal adjoining joints on STIR MRI. The present study showed that inflammation was always present at the pars defects and in some cases at the adjoining facet joints. Thus, it is not difficult to understand how, during sports activity, inflammation may first occur at the pseudoarthrotic site and then spread to the adjoining facet joints. This mechanism could cause LBP associated with terminal-stage (pseudoarthrotics) spondylolysis in athletes.

Archives of Orthopaedic and Trauma Surgery


Modic Type 1 Change in Lumbar Spine in Golfers.

Low back pain (LBP) is the most prevalent musculoskeletal complaint among professional and amateur golfers; however, associated radiological changes in golf-related LBP have not been examined in the literature. We suspect that Modic Type 1 changes in the lumbar spine are linked to golf-related LBP. In this retrospective case series, four middle-aged golfers (one professional and three high-level amateurs) presented to our clinic with LBP. Inflammation of the right side of endplates in the lumbar spine was suspected based on Modic Type 1 changes detected by magnetic resonance imaging (MRI) in each patient. All four cases were diagnosed with right-sided endplate inflammation and administered intradiscal steroid injections with a non-steroidal anti-inflammatory drug (NSAID). Treatment swiftly alleviated LBP and diminished Modic Type 1 changes on follow-up MRI 3-6 months later in all four patients. We suggest that Modic Type 1 changes play a significant role in the diagnosis and treatment of golf-related LBP.


Anterior Thoracolumbar Reconstruction Surgery for Late Collapse Following Vertebroplasty: Report of Three Cases.

Although vertebroplasty (VP) using polymethylmethacrylate (PMMA) is thought to be an effective procedure for osteoporotic vertebral compression fractures, several complications have been reported. In this paper, we present three patients who developed local kyphotic deformity as a result of late collapse of the cemented vertebrae. In all patients we safely removed the PMMA block through an anterior approach and anterior reconstruction was performed successfully. In only one patient who had a three column unstable injury with fractured posterior elements was additional posterior spinal fixation needed. In conclusion, VP is thought to be an effective and minimal invasive technique to treat osteoporotic compression fractures in older patients. Once collapse or nonunion of the treated vertebral body occurs, however, removal of the cement and anterior reconstruction may be required to realign of the affected segments and reconstruct the spine.

The Journal of Medical Investigation : JMI


Biomechanical rationale of sacral rounding deformity in pediatric spondylolisthesis: a clinical and biomechanical study.

Rounding surface of the sacral dome and wedging deformity of the vertebral body are commonly observed in patients with isthmic spondylolisthesis. Recently, an animal study showed that the deformity can be caused by the growth plate involvement in the immature pediatric vertebral body after biomechanical alteration due to the pars defects. However, the pathomechanism and biomechanics of these deformities have yet to be clarified. To demonstrate that the sacral rounding deformity observed in pediatric patients with spondylolisthesis can be reversed, and to understand the pathomechanism of the deformity from the biomechanical standpoint by analyzing changes of stress around the growth plate of the vertebral body due to spondylolysis. Three-dimensional finite element pediatric lumbar models of the L3-L5 segment were utilized. Unlike the adult model, this pediatric model had growth plates and apophyseal rings. We analyzed stress distribution in response to 351°N axial compression and 10 N m moment in flexion, extension, lateral bending, and axial rotation. Bilateral spondylolysis was created in the model at the L4 level. The stress in the bilateral defect model was compared to the intact model predictions and the results obtained in the pediatric patients with sacral rounding deformity. Two patients presented rounding deformity of the anterior upper corner at S1 at the initial visit. They were asked to stop sports activities and use a soft trunk brace. Twelve months later, no rounding deformity was observed on the radiographs indicating that this deformity was reversible in pediatric cases. The biomechanical study indicated that in the pediatric spondylolytic spine, mechanical stress increased at the anterior upper corner during lumbar motion. In the presence of spondylolysis, mechanical stress increases in the growth plate at the anterior upper corner. Repetitive increases of mechanical stress may cause rounding deformity of the sacral dome mediated by growth plate involvement. When mechanical stress at the growth plate is reduced by wearing a brace, the proper functioning of the growth plate can help to remodel the sacral dome to its normal shape.


Osseous erosion by herniated nucleus pulposus mimicking intraspinal tumor: a case report.

Erosion of spinal osseous structure, so-called scalloping, has been rarely reported associated with herniated nucleus pulposus (HNP). We report a rare case of HNP causing erosion of the spinal osseous structure (including lamina). The patient was an 81-year-old woman with 3-year history of low-back pain and left leg radiating pain. Muscle weakness of the left leg was also apparent. Computed tomography following myelography showed severe compression of the dural sac at the level of L3-L4; furthermore, erosion of the lamina, pedicle, and vertebral body was noted, indicating that the space-occupying mass was most probably a tumorous lesion. The mass also showed calcification inside. During the surgery, the mass was confirmed to be an HNP with calcification. Following resection, the pain disappeared. Surgeons should be aware of the possibility of scalloping of the vertebrae caused by HNP mimicking a tumorous lesion.

Journal of Orthopaedics and Traumatology


Adolescents with symptomatic laminolysis. -Report of two cases-.

Retroisthmic cleft refers to a cleft in the lamina and is rarely reported. It was first described by Brocher, and later Wick et al. proposed the term "laminolysis" to describe the retroisthmic cleft by analogy with the nomenclature of the applied stress fracture of the pars interarticularis (spondylolysis) and the pedicle (pediculolysis). In this paper, we describe two adolescent sports players with symptomatic lumbar laminolysis. Both improved significantly after adequate conservative treatment. Knowledge of laminolysis in adolescent patients with low back pain is necessary to avoid overlooking it and late diagnosis. For correct diagnosis, multidetector three-dimensional computed tomography (CT) is suggested. In addition, magnetic resonance imaging (MRI) also allows detection of inflammation in the defects.


Spondylolysis originates in the ventral aspect of the pars interarticularis: a clinical and biomechanical study.

Lumbar spondylolysis is a stress fracture of the pars interarticularis. We have evaluated the site of origin of the fracture clinically and biomechanically. Ten adolescents with incomplete stress fractures of the pars (four bilateral) were included in our study. There were seven boys and three girls aged between 11 and 17 years. The site of the fracture was confirmed by axial and sagittal reconstructed CT. The maximum principal tensile stresses and their locations in the L5 pars during lumbar movement were calculated using a three-dimensional finite-element model of the L3-S1 segment. In all ten patients the fracture line was seen only at the caudal-ventral aspect of the pars and did not spread completely to the craniodorsal aspect. According to the finite-element analysis, the higher stresses were found at the caudal-ventral aspect in all loading modes. In extension, the stress was twofold higher in the ventral than in the dorsal aspect. Our radiological and biomechanical results were in agreement with our clinical observations.

The Journal of Bone and Joint Surgery. British Volume


Complications of endoscopic lumbar decompression surgery.

Endoscopic lumbar decompression is useful for the treatment of various spinal conditions and is being performed in an increasing number of patients worldwide. We reviewed the surgery-related complications in patients who underwent endoscopic surgery and discuss the learning curve for this procedure. Since the first case in August 2000, a total of 138 patients have undergone endoscopic posterior decompression surgery. Of these, there were 74 patients with Herniated Nucleus Pulposus (HNP), 57 with Lumbar Canal Stenosis (LCS), and 7 with other conditions. From 2003 to 2005, the senior surgeon took a sabbatical, and no endoscopic surgery was conducted. We divided the cases based on the date of surgery: there were 62 patients in the early (E) group (before September 2003), and 76 in the late (L) group (from January 2006 to April 2008). We compared the incidence of surgery-related complications between 2 disease types as well as between the E and L groups. We encountered 11 complications, which included 6 dural tears, 2 post-surgical hematomas, 2 neural complications and 1 fracture of the inferior articular process. The incidence of surgery-related complications was 8.6%. The incidences of complications were 8.1% and 9.3% for HNP and LCS, respectively, and 11.3%, and 5.3% in the E and L groups, respectively. The incidence was particularly high (16.7%) in the E group with LCS. There is a steep learning curve for endoscopic surgery. Based on the data, surgeons should start performing endoscopic techniques for LCS after gaining enough experience of endoscopic surgery for HNP.


Congenital absence of lumbosacral articular facet joint associated with conjoined nerve root.

We report a rare case of congenital absence of the L5-S1 facet joint, which was associated with a conjoined nerve root. Combination of these two anomalies has been quite rarely reported in the literature. A 39-year-old man presented with acute low back pain and right leg radiating pain. Muscle weakness and sensory disturbance of the right leg were also apparent in the region innervated by L5 and S1 nerve roots. Preoperative multidetector three-dimensional computed tomography (3D-CT) showed complete absence of the right S1 superior articular process. Magnetic resonance (MR) images showed lumbar disc herniation at right L5-S1 level that migrated cranially. Intraoperative findings revealed that the right L5 nerve root and S1 nerve root were conjoined, and the conjoined nerve root was compressed by L5-S1 disc herniation, which led to impairment of the conjoined nerve root by a single-level lumbar disc herniation. After removal of the disc herniation, his right leg pain immediately subsided, however muscle weakness and sensory disturbance persisted. Surgeons should be aware of this nerve root anomaly when examining a patient who shows an unusual clinical presentation and/or congenital osseous anomaly.


Incidence and etiology of lumbar spondylolysis: review of the literature.

Lumbar spondylolysis is a defect of the pars interarticularis known to occur as a stress fracture. Its incidence varies considerably depending on ethnicity, sex, and sports activity. However, there are few literature reviews describing its incidence in different ethnic groups or in people who engage in different sports. We reviewed the most relevant articles on spondylolysis published in scientific journals. First, we focused on its incidence in various ethnic groups distributed by sex, the familial occurrence, and in patients with relevant diseases. Second, we focused on the incidence of spondylolysis in relation to the sports practiced by the patients. Although placing special emphasis on the incidence of lumbar spondylolysis in the general population in Japan, we also reviewed the Japanese and English literature to investigate its incidence among those who engage in different sports. The incidence of lumbar spondylolysis in the general Japanese population was 5.9%. Most studies report that the incidence in higher in male subjects than in female subjects. We found that Japanese rugby and judo players were prone to suffer lumbar spondylolysis, at an incidence of about 20%. However, the incidence for Japanese professional soccer and baseball players was much higher, at 30%, which was more than five times the incidence in the general Japanese population. The incidence of lumbar spondylolysis varies depending on ethnicity, sex, family history, relevant disease, and sports activity.


Significance of magnetic resonance imaging signal change in the pedicle in the management of pediatric lumbar spondylolysis.

Prospective study. To investigate the time course of signal changes in the adjacent pedicle in fresh pediatric lumbar spondylolysis. A recent study reported that high signal change (HSC) on T2-magnetic resonance image (MRI) in the pedicle adjacent to the pars interarticularis could be an indicator of early spondylolysis. In addition, the HSC-positive pars defects showed significant better bony healing than the HSC-negative pars defects. However, there has been no report on the time course and the duration of HSC. We prospectively investigated 10 boys and 5 girls with fresh lumbar spondylolysis showing HSC in the adjacent pedicle. Their mean age was 15.1 years, ranging from 10 to 17 years. Two patients had multilevel unilateral spondylolysis. Among 15 patients, HSC was found in 22 (12 unilateral and 5 bilateral) pedicles. At the first presentation, the diagnosis of spondylolysis was made based on the plain radiograph findings, multidetector computed tomograms (CTs), and MRI. Every month from the first presentation, follow-up MRIs were taken. When HSC disappeared, multidetector CT was taken to confirm bony healing of the pars defect. Bony healing of the pars was obtained in 21 out of 22 defects. The bony healing rate was 95.6%. In 19 pedicles of 12 patients, HSC gradually diminished by every month until it disappeared 3 months later, and radiologic osseous healing was confirmed by CT in all but 1 patient. In the 3 remaining pedicles of 3 patients, HSC took more than 4 months to disappear. In this study, HSC disappeared in most pedicles on the 3-month follow-up MRI. In patients who did not comply with treatment, HSC tended to last longer. These results led us to hypothesize that MRI at the third month during follow-up can indicate whether the conservative treatment is being successful or not.


Significance of surgical treatment for severe dystrophic changes in the cervical spine associated with neurofibromatosis type I: a case report.

There have been several reports about the treatments for dystrophic changes in the thoracic or lumbar spines owing to neurofibromatosis type-1. However, dystrophic changes in the cervical spine have been rarely reported. In this study, we present the case of a 13-year-old boy with severe dystrophic changes (dural ectasia) in the cervical spine owing to neurofibromatosis type-1. Although he had no neurological deficit, imaging studies revealed cervical kyphotic deformity and osteolysis of vertebral bodies. Thinning of vertebral bodies and laminae from C2 to C5 was remarkable, suggesting that the patient was at risk of suffering a spinal injury. The patient underwent cervical posterior fusion. At the 2-year follow-up examination, there was complete posterior bony fusion and no obvious progression.

Journal of Pediatric Orthopaedics. Part B


Minimally invasive endoscopic bilateral decompression with a unilateral approach (endo-BiDUA) for elderly patients with lumbar spinal canal stenosis.

Endoscopic spinal surgery has become increasingly common year for year because it is a minimally invasive procedure. In our hospital, we introduced endoscopic bilateral decompression with a unilateral approach (endo-BiDUA) in 2006. In this paper, we review clinically and radiographically the elderly patients who underwent the endo-BiDUA. Fifteen patients aged over 65 years were included in this review. They had undergone endo-BiDUA between January 2006 and July 2008. Operation time, blood loss, complications, clinical outcome using the Japanese Orthopedic Association (JOA) score, and enlargement ratio of the dural tube on magnetic resonance imaging (MRI), were evaluated. The mean operation time per level of endo-BiDUA was 144 min. Blood loss was about 60.2 mL. One patient had a post-surgical hematoma and required an additional laminectomy and removal of the hematoma 2 days after the surgery. No other complications such as dural tear, nerve root injury, or infection were encountered. All patients but one, who had a post-surgical hematoma, could start walking within 2 days following the surgery. Before surgery, the mean JOA score was 17.0 and it improved to about 23.3 after the surgery. The area of the dural tube increased to 408.0% after the surgery (range: 211-774%). Endo-BiDUA facilitated the return of elderly patients with lumbar spinal canal stenosis to their original daily activities.


Diffuse arachnoid ossification and multiple arachnoid cysts presenting with progressive thoracic myelopathy.

An ossified arachnoid membrane combined with cystic formation is rarely reported as a cause of spinal cord compression. We report the case of a 60-year-old man who presented with diffuse ossification of the arachnoid membrane (arachnoid ossification) and multiple cystic changes (arachnoid cyst) at the thoracic and lumbar spine. The lesions were surgically removed and progressive deterioration was prevented, although no marked improvement of neurological symptoms was attained.


Hematoma in the Cervical Ligamentum Flavum. Report of a Case and Review of the Literature.

Hematoma of the cervical ligamentum flavum is very rare, and its pathogenesis is unknown. We describe a case of ligamentum flavum hematoma in the cervical spine causing severe myelopathy. Postoperative histological examination suggested it was the result of the rupture of a hemangioma or of an arteriovenous malformation in the ligamentum flavum. After removal of the lesion, the patient's condition immediately improved. Review of all three reported cases, including this one, showed that complete resection of the mass resulted in immediate relief of symptoms of incomplete paraplegia. The findings of magnetic resonance imaging (MRI) of the hematoma may vary with time, and they may show no characteristic intensity. However, MRI of this case revealed that the tissues surrounding the mass were enhanced with gadolinium diethylene triamine penta-acetic acid, and an area of homogeneous iso-intensity was clearly surrounded by a low-intensity area (flavum) on T2-weighed short-tau inversion recovery images. These findings could be characteristic of the ligamentum flavum hematoma and might help in the differentiation from a cervical epidural hematoma.


Causes of radiculopathy in young athletes with spondylolysis.

The main clinical symptom of lumbar spondylolysis is lower back pain. Radiculopathy rarely occurs without vertebral slippage. Hypothesis Spondylolysis in young athletes can cause lumbar radiculopathy. Case series; Level of evidence, 4. Ten patients (7 males and 3 females) were included in this study. The age of the patients ranged from 12 to 27 years. We employed plain radiography, computed tomography, magnetic resonance imaging, and selective radiculography if needed. The pathomechanism was classified into nonspondylolytic radiculopathy (3 cases) and spondylolytic radiculopathy (7 cases). In the nonspondylolytic group, 1 patient had a juxta-facet cyst at L4-5 and 2 patients had a herniated nucleus pulposus. In the other group, spondylolytic-related factors caused radiculopathy, and spondylolysis was in the early or progressive stage in all 7 patients. Radiologic findings indicated that radiculopathy was caused by extraosseous hematoma or edema in the vicinity of the fracture site. The radiculopathy disappeared within a month of nonoperative management, and radiologic abnormalities disappeared 3 to 6 months later. Radiculopathy can occur together with lumbar spondylolysis without slippage in young athletes. We propose extra-osseous hematoma or edema at the site of spondylolysis as the unique pathomechanism causing radiculopathy in young athletes. Radiculopathy is rare in athletes with spondylolysis. Magnetic resonance imaging is a useful tool to clarify the pathologic changes that induce the radiculopathy for both spondylolytic and nonspondylolytic factors.


Radiographic comparison between male and female patients with lumbar spondylolysis.

We studied the lumbar spines of 117 adults (39 women and 78 men) with spondylolysis unrelated to low back pain using multidetector computed tomography (CT). Of the 117 subjects with spondylolysis, including five with multiple-level spondylolysis, there were 124 vertebrae with spondylolysis. In adult lumbar spines with unilateral spondylolysis, there was no significant difference between the incidence of spondylolisthesis in female and male subjects. However, in those with bilateral spondylolysis, there was a significantly higher incidence of spondylolisthesis in female subjects (90.9%) than in males (66.2%). Furthermore, females with bilateral spondylolysis had significant more slippage than males. Lumbar index and lumbar lordosis were not significantly different between male and female subjects, and did not significantly correlate with slippage. In conclusion, to treat acute spondylolysis in adolescents, it is important to obtain bony union at least unilaterally, especially in female subjects, to prevent further slippage.

The Journal of Medical Investigation : JMI


Incidence of lumbar spondylolysis in the general population in Japan based on multidetector computed tomography scans from two thousand subjects.

Epidemiological analysis using CTs. To investigate the true incidence of lumbar spondylolysis in the general population in Japan. Although there have been several reports on the incidence of lumbar spondylolysis, they had some weakness. One of them concerns the subjects investigated, because the incidence of lumbar spondylolysis varies considerably, and some patients are asymptomatic. In addition, most of the past studies used plain radiograph films or skeletal investigation. Therefore, the past reported incidence may not correspond to that of the general population. We reviewed the computed tomography (CT) scans of 2000 subjects (age: 20-92 years) who had undergone abdominal and pelvic CT on a single multidetector CT scanner for reasons unrelated to low back pain. We reviewed them for spondylolysis, spondylolytic spondylolisthesis, and spina bifida occulta (SBO) in the lumbosacral region. The grade (I-IV) of spondylolisthesis was measured using midsagittal reconstructions. Lumbar spondylolysis was found in 117 subjects (5.9%). Their male-female ratio was 2:1. Multiple-level spondylolysis was found in 5 subjects (0.3%). Among these 117 subjects, there were 124 vertebrae with spondylolysis. Of them, 112 (90.3%) corresponded to L5, and 26 (21.0%) had unilateral spondylolysis.SBO was found in 154 subjects. Of them, 25 had spondylolysis (16.2%), whereas, in 1846 subjects without SBO, 92 had spondylolysis (5.0%). The incidence of spondylolysis among the patients with SBO was significantly higher than that in subjects without SBO (Odd ratio was 3.7-fold).Of 124 vertebrae with spondylolysis, 75 (60.5%) showed low-grade (Meyerding grade I or II) spondylolisthesis, and no subject presented high-grade spondylolisthesis. Spondylolisthesis was found in 74.5% of the subjects with bilateral spondylolysis, and in 7.7% of those with unilateral spondylolysis. The incidence of lumbar spondylolysis in the Japanese general population was 5.9% (males: 7.9%, females: 3.9%).


Anterior transvertebral herniotomy for cervical disc herniation: a long-term follow-up study

Retrospective study. To investigate the efficacy and radiologic changes after anterior transvertebral herniotomy (ATH), in patients followed for at least 10 years after the surgery. The theoretical idea of ATH is to remove an extruded herniated mass while preserving disc motion. To our knowledge, no report has been published on the long-term outcome of this procedure. Twenty patients underwent single-level ATH at our institution between 1989 and 1995. Clinical outcome was evaluated by visual analog scale for neck and arm pain according to Japanese Orthopaedic Association (JOA) score, and range of motion (ROM) of the cervical spine. Radiologic outcome was evaluated by measuring disc height and range of intervertebral motion of the site on plain radiographs. We also evaluated the operated and the adjacent segments by magnetic resonance imaging (MRI) for degenerative changes. Fifteen of the 20 patients were evaluated. One patient required additional surgery, 3 patients were lost to follow-up, and 1 patient had died by the time of the evaluation. Therefore, we evaluated the clinical outcome of 15 patients. Both the plain radiographs and MRI were available from 10 patients, and for 3 patients only the plain radiographs were available. Two patients refused x-ray examination at the final follow-up. Regarding clinical outcome, no patient had suffered from neck pain or arm pain. The average visual analog scale was 7.8/100 (%) for neck pain, and 7.0/100 (%) for arm pain. JOA scores improved and remained at a good level. The improvement rate was 88.5%. The average ROM of the cervical spine was 42.7 degrees in flexion, 52.3 degrees in extension, 58.6 degrees in axial rotation, and 25.0 degrees in lateral bending. Although ROM in axial rotation and lateral bending was symmetric, the range was smaller than that in the healthy segments. On plain radiographs, although the disc height in the operated segment was not significantly decreased compared with the other segments, loss of intervertebral motion was noticed on the follow-up roentgenograms in most cases. Only 2 patients had mobility of the operated intervertebral levels (>10 degrees). There was no collapse of the drilled vertebral body in any patient. Four of the 10 patients who underwent MRI showed protrusion of intervertebral discs, including those adjacent to the affected discs. No recurrence of disk herniation at the involved level was seen on the follow-up MRI. In conclusion, ATH provided a good clinical outcome that was maintained for a long time. Although intervertebral motion at the operated level decreased to some extent, degenerative changes at the adjacent levels were not enhanced.

Journal of Spinal Disorders & Techniques


Minimally invasive technique for direct repair of pars interarticularis defects in adults using a percutaneous pedicle screw and hook-rod system.

In this report, the authors described a new minimally invasive technique to repair pars interarticularis defects in adults. The well-established technique using the pedicle screw (PS) and hook-rod system was modified. First, bilateral PSs were inserted percutaneuosly using the Sextant system. Then, through a small skin incision (3-4 cm), an illuminated tubular retractor (Quadrant system; Medtronic Sofamore Danek) was inserted into the pars defect. When this system is used, it is not necessary to detach all the back muscles to access the lytic part. The bursa and fibrocartilaginous mass near the defects were removed. After decortication of the pseudarthrosis at the spondylolytic level, bone grafts were implanted. Finally, the hook part of a hook-rod system was attached to the lamina and the rod was secured at the tulip head of the PSs. The authors performed this procedure in 2 adult patients, 32 and 24 years of age. Immediately after surgery both patients' low-back pain disappeared, and by 3 months postoperatively both had returned to their original work or sports activities.


Intramedullary schwannoma with calcification of the epiconus.

There have been few reports on intramedullary ancient schwannoma. Schwann cells are generally present in the nerve root, not in the spinal cord. Thus, intramedullary schwannomas are rare, and in most cases there is cyst formation without calcification. To report a patient with intramedullary ancient schwannoma at the epiconus together with a review of the previously published cases. Case report. A 78-year-old woman. Retrospective case review. DESCRIPTION OF THE CASE: A 78-year-old woman had presented with severe weakness of the lower extremities, increased patellar reflex, and sensory disturbance of the entire lower extremities. Magnetic resonance imaging showed a tumorous mass in the intramedullary region of epiconus at T11-L1, and computed tomography revealed calcification in the tumor. She underwent total resection of the tumor. Histopathological findings were consistent with the diagnosis of ancient schwannoma. After the operation, although lower extremities weakness and sensory disturbance deteriorated transiently, lower leg pain disappeared. At the final follow-up of 10 months after the operation, lower leg pain did not relapse. We reported a rare case presenting epiconus syndrome due to intramedullary ancient schwannoma, which should be considered for the differential diagnosis of a tumor that shows calcification.


Fresh stress fractures of lumbar pedicles in an adolescent male ballet dancer: case report and literature review.

Stress fracture in the pars interarticularis is a common cause of low back pain in young athletes. Pedicle stress fractures have also been reported in adolescent sport players, and most of them were associated with contralateral spondylolysis. Only a few cases with bilateral pedicle stress fractures have been reported. We report a 14-year-old ballet dancer with fresh bilateral pedicle fractures treated conservatively, together with a review of the literature.

Archives of Orthopaedic and Trauma Surgery


Conservative treatment of lumbar spondylolysis in childhood and adolescence: the radiological signs which predict healing.

It has been noted that bony union of a pars defect can be achieved in children if they wear a trunk brace. Our aim was to evaluate how the stage of the defect on CT and the presence or absence of high signal change in the adjacent pedicle on T2-weighted MRI were related to bony healing. We treated 23 children conservatively for at least three months. There were 19 boys and four girls with a mean age of 13.5 years (7 to 17). They were asked to refrain from sporting activity and to wear a Damen soft thoracolumbosacral type brace. There were 41 pars defects in 23 patients. These were classified as an early, progressive or terminal stage on CT. The early-stage lesions had a hairline crack in the pars interarticularis, which became a gap in the progressive stage. A terminal-stage defect was equivalent to a pseudarthrosis. On the T2-weighted MR scan the presence or absence of high signal change in the adjacent pedicle was assessed and on this basis the defects were divided into high signal change-positive or -negative. Healing of the defect was assessed by CT. In all, 13 (87%) of the 15 early defects healed. Of 19 progressive defects, only six (32%) healed. None of the seven terminal defects healed. Of the 26 high signal change-positive defects 20 (77%) healed after conservative treatment whereas none of the high signal change-negative defects did so. We concluded that an early-stage defect on CT and high signal change in the adjacent pedicle on a T2-weighted MR scan are useful predictors of bony healing of a pars defect in children after conservative treatment.

The Journal of Bone and Joint Surgery. British Volume


Cervical and upper thoracic screwing for spinal fusion: strategy for its safe insertion to avoid major complications.

There are several screwing techniques to attain cervical fusion such as pedicle screw, lateral mass screw, facet screw, transarticular and laminar screw. Each screwing technique has advantages and disadvantages. In this study, we introduce our strategy for safe screwing and its clinical results. Our strategy is as follows: lateral mass screw for C1, 3, 4, 5, 6 and pedicle screw for C2, 7, and thoracic level. When the C2 pedicle is thinner than 3.5 mm, we use C2 laminar screws. We do not use Magerl transarticular screw or facet screw; 146 screws were inserted in 17 patients. There were no major complications such as spinal cord and nerve root injury. We did not observe vertebral arterial injury either. Of the 146 screws, 141 (97.0%) were accurately inserted. As for lateral mass screwing by Roy-Camille's technique and C2 laminar screwing, all screws were inserted in the appropriate site (100%) without any complications. Five pedicle screws were misplaced. Of the 57 pedicle screws, 5 showed a minor tear of the wall at C7, Th1 and Th3, the success rate for all pedicle screws was 91%. All showed solid fusion. For cervical screwing the most important aspect should be safety to avoid severe morbidity. Our strategy, which consists in the combined use of pedicle, lateral mass and laminar screwing, is safe and reliable.


Cervical spondylolysis in a judo player. A case report and biomechanical analysis.

A case report and a biomechanical study using a finite element method. To report a case with the cervical spondylolysis and to understand the biomechanics of the cervical spine with spondylolysis at C6. Cervical spondylolysis, although not a common spinal disorder, can occur in athletes. Presently, the exact pathology, natural history and biomechanics are not known. Thus, treatment strategies for this disorder in athletes are in controversy. To treat and/or advise patients with cervical spondylolysis, the cervical spine biomechanics regarding this disorder should be understood. A case of a 12-year-old male judo player is presented. The patient presented with occipital and upper neck pain. Plain radiographs, reconstructed CT scan and MRIs of this patient were reviewed. Biomechanically, stress distributions were analyzed in response to 73.6 N axial compression and 1.5-Nm moment in flexion, extension, lateral bending, and axial rotation using a FE model of the intact ligamentous C3 to C7 segment. Bilateral spondylolysis was created in the model at C6. The stress results from the bilateral defect model were compared to the intact model predictions. Plain radiographs showed bilateral C6 spondylolysis, and grade I spondylolisthesis. MRI showed mild disc degeneration at C6/7. With conservative treatment, the symptoms disappeared. In the spondylolysis model, the maximum Von Mises Stresses at C6/7 increased in all cervical spine motions, as compared to the intact case. Specifically, in axial rotation, the stress increase was 3.7-fold as compared to the intact model. The range of motion at C6/7 increased in the spondylolysis model as well. Again, during axial rotation, the increase in motion was 2.3-fold when compared to the intact model. Cervical spondylolysis can cause biomechanical alterations, especially in axial rotation, leading to increased disc stresses and range of motion. The increased stresses in the disc and the hypermobility would be a dangerous condition for athletes participating in contact sports such as judo. Thus, we recommended that judo players with cervical spondylolysis should change to non-contact sports, such as jogging.


Newly occurred L4 spondylolysis in the lumbar spine with pre-existence L5 spondylolysis among sports players: case reports and biomechanical analysis.

STUDY DESIGN: Case series and a biomechanical study using a finite element (FE) analysis. OBJECTIVES: To report three cases with multi-level spondylolysis and to understand the mechanism biomechanically. BACKGROUND: Multi-level spondylolysis is a very rare condition. There have been few reports in the literature on multi-level spondylolysis among sports players. METHODS: We reviewed three cases of the condition, clinically. These patients were very active young sports players and had newly developed fresh L4 spondylolysis and pre-existing L5 terminal stage spondylolysis. Thus, we assumed that L5 spondylolysis may have increased the pars stress at the cranial adjacent levels, leading to newly developed spondylolysis at these levels. Biomechanically, we investigated pars stress at L4 with or without spondylolysis at L5 using the finite element technique. RESULTS: L4 pars stress decreased in the presence of L5 spondylolysis, which does not support our first hypothesis. CONCLUSIONS: It seems that multi-level spondylolysis may occur due to genetic and not biomechanical reasons.


Pseudoaneurysm of the thoracoabdominal aorta caused by the severe migration of an anterior spinal device. A case report.

Case report. To describe the case of pseudoaneurysm of the thoracoabdominal aorta caused by the severe migration of an anterior spinal device 5 years after surgery. Case report. A 70-year-old woman was referred to us because of migrated anterior spinal devices and a pseudoaneurysm of the thoracoabdominal aorta. This patient had undergone anterior corpectomy and spinal fusion from Th12 to L2 because of delayed palsy after a burst fracture using a smooth rod Kaneda device (SRK) with bioactive ceramic (apatite-wollastonite containing glass ceramic) at a local hospital. She had persistent low back pain after the surgery. Five years after the initial surgery, the patient was referred to us because of increasing of her low back pain and the migrated SRK devices shown on plain X-ray films. An enhanced computed tomography scan taken in our hospital clearly showed a pseudoaneurysm of the thoracoabdominal aorta surrounding the SRK devices. The pseudoaneurysm was resected, the aortic defect was repaired with an artificial patch, and the migrated SRK devices were removed. The pseudoaneurysm of the aorta can occur secondary to a migrated anterior spinal fixation device and can be successfully treated by revision anterior surgery with vascular repair and implant removal.


Minimally invasive excision of lumbar epidural lipomatosis using a spinal endoscope.

In this report, we describe the case of a patient with a long-term radiculopathy due to epidural lipomatosis at the L3-4 intervertebral disc level. The fatty tissue was located on the dorsal side of the dural sac in the spinal canal and compressed the dural sac. The fatty tissue was removed endoscopically. After surgery, the symptoms disappeared, and neurological deficits normalized. We would like to state that epidural lipomatosis is a good candidate for minimally invasive endoscopic surgery because of its anatomic location.


Myelopathy in a 6-year-old girl caused by neurofibromatosis Type 1: a case report

Even when there is radiological evidence of spinal involvement, young patients with neurofibromatosis Type 1 (NF-1) seldom have symptoms. We report the case of a child who developed rapidly progressive myelopathy. To describe a technique used to prevent postoperative spinal deformity and instability, after removal of a dumbbell-shaped tumor in a 6-year-old child. Case report. A 6-year-old female. Retrospective case review. The patient underwent a resection of the cervical dumbbell tumor using an osteoplastic laminectomy technique to prevent postoperative spinal deformity. At 2-year follow-up, there was no clinical or radiographic evidence of complications or spinal kyphotic deformity. The case of a 6-year-old girl with cervical myelopathy caused by NF-1 was reported. The tumor was removed after osteoplastic laminectomy, which could prevent postoperative kyphotic deformity.


Radiological features of lumbar spinal lesions in patients with rheumatoid arthritis with special reference to the changes around intervertebral discs.

Compared with the cervical spine, little attention has been paid to rheumatoid arthritis (RA)-related lumbar disorders. Only a few articles have described the status of the lumbar spine affected by RA based on plain X-ray films and magnetic resonance imaging (MRI). To describe the features and prevalence of radiological changes of the lumbar spine of patients with RA and to clarify the correlations of such features with disease activity. Transverse radiological study. We radiographically examined 104 patients with RA whose age ranged from 21 to 78 years (mean, 51.0). In each, the duration of RA exceeded 10 years (mean, 17.7 years). Clinical outcomes included Ochi's classification, Lansbury index, C-reactive protein (CRP) (mg/dL), rheumatoid factor (RF) (U/mL), and platelet (count/mm). Radiological outcomes included radiography and MRI. One hundred four RA patients were included in this study regardless of the presence/absence of low back pain. We examined discs from L1-2 to L5-S, including endplates, in each patient on plain X-ray films and magnetic resonance images and used a comprehensive grading system to evaluate each feature of the lumbar spine affected by RA based on the present findings and published reports. The correlations of these radiological features with RA activity and Ochi's classification were examined. To quantify disease activity, we determined the Lansbury index, serum CRP (mg/dL), RF (U/mL), and platelet count (count/mm) at the time of radiological examinations. Of the 104 patients, 47 (45.2%) exhibited a lumbar lesion. There were two types of lumbar disc lesions related to RA: disc narrowing and disc ballooning. The Lansbury index of patients with the most severe lesions was significantly higher than that of patients with less severe lesions (p<.01). The frequency of lumbar involvement also increased as the number of affected peripheral joints increased, and Ochi's classification appeared to be useful in predicting the occurrence of lumbar lesions. Of 104 patients, 47 (45.2%) exhibited abnormalities on X-ray films and MRI. There were two types of disorders, disc narrowing and disc ballooning. Both the Lansbury index and Ochi's classification reflected the severity of lumbar lesions in RA patients.


Vertebral rounding deformity in pediatric spondylolisthesis occurs due to deficient of endochondral ossification of the growth plate: radiological, histological and immunohistochemical analysis of a rat spondylolisthesis model.

A study using rat spondylolisthesis models. To clarify pathomechanism of vertebral rounding deformity in pediatric spondylolisthesis. For high-grade slippage, rounding of sacrum surface associated with L5 spondylolisthesis is reported to be the most responsible risk factor. However, the exact pathomechanism of the rounding deformity is yet to be clarified. Spondylolisthesis rat model (4-week-old) was used. Radiographs were taken weekly for 5 weeks after the surgery. The lumbar spines were harvested for histology. Hematoxylin and eosin, alcian blue staining, and tartrate-resistant acid phosphatase staining were used. Immunohistochemically, the growth plate cartilage was studied for type II and X collagen. A modified bone histomorphometric analysis was also performed. Radiographs showed slippage 1 week after surgery. Rounding deformity was obvious 2 weeks after surgery. The rounding deformity progressed with time. Three weeks after surgery, the specific columns of growth plate were unclear at the anterior corner, which corresponded to the rounding surface observed on radiographs. Instead, a huge mass of cartilage was observed at that site. Tartrate-resistant acid phosphatase-positive cells were observed in the vicinity of the growth plate except in relation with the anterior corner. The growth plate and cartilage mass at the anterior corner stained positive for type II collagen. Chondrocytes in the hypertrophied layer stained positively for type X collagen; however, staining was faint at the anterior corner. The results suggested that the chondrocytes at the anterior did not form, morphologically and functionally, the normal growth plate. From histomorphometrical analysis, the normal posterior growth plate made endochondral bone growth in 510 +/- 20 microm for a week, whereas the anterior corner in 200 +/- 15 microm. Deficient endochondral ossification of the growth plate in the anterior upper corner of the vertebra could be the pathomechanism of the rounding deformity of the sacrum.