Transforaminal full-endoscopic ventral facetectomy: mid-term results and factors associated with poor surgical outcomes.

Full-endoscopic spine surgery (FESS) is a well-established procedure for herniated nucleus pulposus. It is a minimally invasive surgery that can be performed under local anesthesia through only an 8-mm skin incision. With improvements in surgical equipment such as high-speed drills, the indications for FESS have expanded to include lumbar spinal stenosis (LSS). We perform transforaminal full-endoscopic ventral facetectomy (TF-FEVF) for unilateral nerve root-type lateral recess stenosis (LRS) using a transforaminal approach under local anesthesia. PURPOSE The aim of this study was to examine the postoperative results of TF-FEVF for LRS and to identify factors associated with poor surgical outcomes. STUDY DESIGN Retrospective study. PATIENT SAMPLE 85 patients who underwent TF-FEVF for LRS under local anesthesia. OUTCOME MEASURES Clinical outcomes were determined by visual analogue scale (VAS) and the modified MacNab criteria. Evaluation was performed using magnetic resonance imaging (MRI), computed tomography (CT), and flexion-extension radiographs. METHODS This study involved 85 patients (47 male, 38 female) who underwent TF-FEVF for LRS. The mean age was 70.5 years and the mean follow-up duration was 14.8 months. Data were collected on sex, age, level of operation, diagnosis, history of spine surgery at the same level, and duration of follow-up. The diagnosis was categorized as lumbar spinal stenosis with or without disc bulging. Clinical evaluation was performed using the VAS and modified MacNab criteria. MRI was used to evaluate the degree of disc degeneration, vertebral endplate degeneration, disc height, thickening of the ligamentum flavum, and stenosis. Bony stenosis was evaluated using CT. Sagittal translation and sagittal angulation were also measured by flexion-extension radiographs, and Cobb angle was measured using a standing front view radiograph. All variables were compared between patients with excellent/good outcomes (E/G group) and those with fair/poor outcomes (F/P group) using the modified MacNab criteria. Results Postoperative VAS showed that leg pain decreased from 59.0±28.6 preoperatively to 17.9±27.2 at final follow up (P<0.01), and that lower back pain also decreased from 60.7±26.6 preoperatively to 27.3±28.6 at final follow up (P<0.01). According to the modified MacNab criteria, the results during the final follow-up were excellent in 39 cases, good in 21 cases, fair in 13 cases, and poor in 12 cases. There were no significant differences in sex, age, diagnosis, history of spine surgery, and duration of follow-up periods between the 60 cases (70.6%) in the E/G group and the 25 cases (29.4%) in the F/P group. Imaging evaluation revealed statistically significant differences between the E/G group and the F/P group in intervertebral angle flexion (3.2° vs 0.4°, P<0.05), sagittal angulation (4.3° vs 8.1°, P<0.05), slip in flexion (0.9mm vs 2.8mm, P<0.05), sagittal translation (0.7mm vs 1.6mm, P<0.05), and Cobb angle (-0.5° vs -1.9°, P<0.05). Conclusion Mid-term results of TF-FEVF were generally favorable; factors contributing to good or poor TF-FEVF outcomes were large sagittal angulation, large sagittal translation, and concave side.

Journal of Neurological Surgery. Part A, Central European Neurosurgery


Morphological Evaluation of Lumbar Facet Joints in Professional Baseball Players.

The facet joints of professional baseball players were enlarged asymmetrically, with different tendencies observed between pitchers and fielders. Although pitching and batting are movements that transmit the rotation from the lower limbs to the upper limbs, the effects of rotation and lateral flexion were associated significantly with facet joint hypertrophy.


Advantages of revision transforaminal full-endoscopic spine surgery in patients who have previously undergone posterior spine surgery.

Revision lumbar spine surgery via a posterior approach is more challenging than primary surgery because of epidural or perineural scar tissue. It demands more extensive removal of the posterior structures to confirm intact bony landmarks and could cause iatrogenic instability postoperatively; therefore, fusion surgery is often selected. However, adjacent segment disease after fusion surgery could be a problem, and further exposure of the posterior muscles could result in multiple operated back syndrome. To address these problems, we now perform transforaminal full-endoscopic spine surgery (TF-FES) as revision surgery in patients who have previously undergone posterior lumbar surgery. There have been several reports on the advantages of TF-FES, which include feasibility of local anesthesia, minimal invasiveness to posterior structures, and less scar tissue with fewer adhesions. To assess the clinical outcomes of revision TF-FES and outline its advantages. Forty-eight consecutive patients who underwent revision TF-FES (at 60 levels) under local anesthesia. Clinical outcomes of TF-FES performed as revision surgery in patients with a history of posterior lumbar spine surgery. Intraoperative blood loss, operating time, and complication rate were evaluated. Postoperative outcomes were assessed using the modified Macnab criteria and visual analog scale (VAS) scores for leg pain, back pain, and leg numbness. We also compared the outcome of revision FES with that of primary FES. Mean operating time was 70.5±14.4 (52-106) min. Blood loss was unmeasurable. The clinical outcomes were rated as excellent at 16 levels (26.7%), good at 28 (46.7%), fair in 10 (16.7%), and poor at 6 (10.0%). The mean preoperative VAS score was 6.0±2.6 for back pain, 6.8±2.4 for leg pain, and 6.3±2.8 for leg numbness. At the final follow-up, the mean postoperative VAS scores for were 4.3±2.5, 3.8±2.6, and 4.6±3.2, respectively. VAS scores for all three parameters were significantly improved (p<0.05). There was no significant difference in operating time, intraoperative blood loss, or the complication rate between revision FES and primary FES. Clinical outcomes of revision TF-FES in patients with a history of posterior lumbar spine surgery were acceptable (excellent and good in 73.4% of cases). TF-FES can preserve the posterior structures and avoid scar tissue and adhesions. Therefore, TF-FES could be an effective procedure for patients who have previously undergone posterior lumbar spine surgery.


Facet Joint Morphology and Tropism in Adolescents: Association with Lumbar Disc Herniation and Spondylolysis.

Facet tropism in adolescents is similar in the axial and sagittal planes. Facet tropism and specific morphology may be related to lumbar disc herniation and spondylolysis in this age group.

The orientation of all lumbar facet joints was measured in the bidirectional planes on computed tomographic images for 191 patients with low back pain. The patients were divided into four groups according to age (<15 or ≥15 y) and sex. The facet joint angle and tropism rate were compared among the groups. Facet tropism was defined as a difference in bilateral angle of >10° in the axial plane and >5° in the sagittal plane. Facet joint orientation was compared among groups using one-way analysis of variance and Tukey's honestly significant difference test or Games-Howell post hoc test and the incidence of facet tropism using the Kruskal-Wallis test with Bonferroni correction. The association of facet tropism with disease was investigated further by analyzing facet joint orientation and the incidence of facet tropism in 116 patients with single-level lumbar disease.


Preoperative Planning Using Three-dimensional Printing for Full-endoscopic Spine Surgery: A Technical Note.

Transforaminal full-endoscopic spine surgery (TF-FESS) is a novel minimally invasive spine surgery that requires only an 8-mm skin incision and causes minimal damage to the paravertebral muscles. To perform TF-FESS safely and efficiently, preoperative planning is quite important as the intervention requires anatomical understanding and high technical skills. Recently, three-dimensional (3D) printing has become a useful tool in various surgeries, and several studies have addressed its efficacy; however, there are no reports on the application of 3D printing to FESS. In this study, we present two cases of severe lumbar deformities for which preoperative 3D printing was useful. The 3D printing enabled the surgeons to visualize and plan the drilling of the superior articular process for a successful foraminoplasty at a low cost. The manufacturing equipment cost about USD 900 and is able to produce an actual-size model at a cost of less than USD 10 per patient. In conclusion, preoperative planning using 3D printing should be adopted to safely perform FESS.


A Technical Pitfall of Decompression with Direct Repair of a Ragged Edge Using the Smiley-Face Rod Method : A Case Report.

The smiley-face rod method has been reported to be a successful technique for reducing slippage and repairing pars defects in lumbar spondylolisthesis. However, we encountered a patient who developed right L5 radiculopathy with muscle weakness after use of the smiley-face rod method. The patient was a 19-year-old female judo player who had undergone direct repair surgery using the smiley-face rod method for terminal-stage lumbar spondylolysis. Postoperatively, she developed paresthesia on the lateral side of the right thigh with weakness of the right tibialis anterior and extensor hallucis longus. Computed tomography showed right foraminal stenosis at L5 with the floating lamina shifted ventrally and apophyseal ring fracture. In this case, the spondylolysis fracture angle differed between the left and right sides, with the fracture line on the right side running more sagittally. As a result, the floating lamina was shifted ventrally on the right side by compression and the right L5 intervertebral foraminal space was narrowed due to the ventral shift in the floating lamina and the apophyseal ring bone fragment. The shape of the fracture line should be examined carefully before surgery to avoid this technical pitfall. J. Med. Invest. 69 : 308-311, August, 2022.

The Journal of Medical Investigation : JMI


Full-Endoscopic Trans-Kambin Triangle Lumbar Interbody Fusion: Surgical Technique and Nomenclature.

Kambin's triangle lies immediately behind the psoas major. Therefore, we consider KLIF as a lateral LIF procedure comparable with oblique or extreme LIF. However, unlike oblique or extreme LIF, there are no major vessels and organs in the surgical field; therefore, KLIF is the safest type of lateral LIF. Furthermore, using the endoscope, we can perform decompression directly using the facetectomy technique.


Hemangioblastoma of the Cauda Equina : A Case Report and Review of the Literature.

Introduction : Hemangioblastoma in the spine mainly occurs at the cervical and thoracic levels and is often associated with von Hippel-Lindau (VHL) syndrome. Here, we reported a quite rare case of spinal sporadic hemangioblastoma arising from the cauda equina. Case presentation : A 66-year-old woman presented with a 5-year history of low back and leg pain. Imaging revealed a hypervascular intradural extramedullary tumor in the lumbar region. Preoperative angiography helped to identify the feeding arteries and draining vein, and so facilitated subsequent tumor resection. The pain was dramatically improved but weakness of the left tibialis anterior and left extensor hallucis longus muscles persisted. Discussion : We reported a rare case of spinal hemangioblastoma arising from the cauda equina. Preoperative angiography may be useful for diagnosis and understanding of the anatomy of feeding veins. J. Med. Invest. 69 : 312-315, August, 2022.


Role of growth plate (apophyseal ring fracture) in causing modic type changes in pediatric low back pain patients.

Diagnostic: individual l cross-sectional studies with consistently applied reference standard and blinding.

A total of 368 MRI obtained for 240 male and 128 female patients under the age of 18 years with complaints of low back/leg pain were retrospectively examined. All changes in signal intensity in the vertebral endplate and subchondral bone on MRI were defined as MCs. We investigated the relationship between MCs and underlying diseases, including lumbar spondylolysis/spondylolisthesis, and conditions of the growth plate in cases with MCs. The degree of disc degeneration in patients with MCs was evaluated using the Pfirrmann grading system.


Planned Four-stage Transforaminal Full-endoscopic Lumbar Decompression under Local Anesthesia in a Patient with Severe Comorbidity.

A 74-year-old man presented with symptoms of intermittent claudication. A diagnosis of lumbar spinal canal stenosis (LSS) at L3/4 and L4/5 was made based on the clinical and radiological findings. Bilateral lateral recess stenosis was detected at both these levels on magnetic resonance imaging (MRI) and on computed tomography (CT) scans obtained after myelography. Four nerve roots were impinged bilaterally at L4 and L5. The initial plan was to perform conventional laminectomy at L3/4 and L4/5 under general anesthesia. However, the neurologists pointed out that the patient had comorbidities of parkinsonism and severe carotid artery stenosis, meaning that an increase or decrease in blood pressure during general anesthesia could cause a stroke. Therefore, we changed the surgical plan to four-stage full-endoscopic ventral facetectomy at L3/4 and L4/5 bilaterally under local anesthesia. There were no surgery-related complications after any of the four operations. The patient's symptoms improved after the final operation and the modified MacNab criteria indicated a good clinical outcome. Full-endoscopic lumbar decompression surgery under local anesthesia may be effective in elderly patients who are in poor general health.


Successful Full Endoscopic Surgery for L5 Radiculopathy Due to L4-5 Discal Cyst and Disc Herniation in a Professional Baseball Player.

Discal cysts are rare intraspinal extradural cysts that communicate with the corresponding intervertebral discs, and the diagnosis is difficult to distinguish from other causes of low back pain and radiculopathy. Optimal management for this type of cyst has not been determined because of its rarity. Here, we report successful treatment of a discal cyst and lumbar disc herniation using full endoscopic surgery in a professional baseball player with a chief complaint of weakness in his left lower leg. He had been treated conservatively but symptoms did not improve. Discography helped us to differentially diagnose discal cyst from other cystic lesions. Conventional surgical treatment would have resulted in considerable loss of baseball playing time for the patient. We opted to perform minimally invasive transforaminal full endoscopic surgery under local anesthesia to treat the discal cyst and lumbar disc herniation simultaneously without resection of bone and ligament handling. We removed the discal cyst and disc herniation, which released tension on the left nerve root at the L5 level, and then performed thermal annuloplasty to avoid recurrence. Postoperative course was good and he returned to play baseball at his original competitive level 3 months later. To our knowledge, there have been no previous reports of successful full endoscopic surgery for discal cyst and lumbar disc herniation performed simultaneously in a professional baseball player. It can be difficult to decide on the proper treatment for discal cysts, but full endoscopic surgery for symptomatic discal cyst might be one good option especially for elite athletes.


Prompt Return to Work after Bilateral Transforaminal Full-endoscopic Lateral Recess Decompression under Local Anesthesia: A Case Report.

Transforaminal full-endoscopic lumbar diskectomy became established early in the 21st century. It can be performed under local anesthesia and requires only an 8-mm skin incision, making it the least invasive disk surgery method available. The full-endoscopic technique has recently been used to treat lumbar spinal canal stenosis. Here, we describe the outcome of simultaneous bilateral decompression of lumbar lateral recess stenosis via a transforaminal approach under local anesthesia in a 60-year-old man. The patient presented with a complaint of bilateral leg pain that was preventing him from standing and walking, and he had been able to continue his work as a dentist by treating patients while seated. Imaging studies revealed bilateral lumbar lateral recess stenosis with central herniated nucleus pulposus at L4/5. We performed simultaneous bilateral transforaminal full-endoscopic lumbar lateral recess decompression (TE-LRD) under local anesthesia. Both decompression and diskectomy were successfully completed without complications. Five days after TE-LRD, he was able to return to work, and 3 months after the surgery, he resumed playing golf. Full-endoscopic surgery under local anesthesia can be very effective in patients who need to return to work as soon as possible after surgery.

Journal of Neurological Surgery. Part A, Central European Neurosurgery


Full-endoscopic trans-Kambins triangle lumbar interbody fusion: technique and review of literature.

Journal of Minimally Invasive Spine Surgery and Technique


Risk Factor for Additional Intravenous Medication during Transforaminal Full-endoscopic Lumbar Discectomy under Local Anesthesia.

Transforaminal full-endoscopic lumbar discectomy (TELD) can be performed under local anesthesia. However, there have been no reports on risk factors for a change in vital signs or the need for additional medications to maintain adequate analgesia during this procedure. The purpose of this study was to identify risk factors for additional intravenous medication during TELD under local anesthesia. The following factors were retrospectively evaluated in 113 consecutive patients who underwent TELD under local anesthesia at our institution: demographic characteristics, radiological features at the intervertebral disc level, distance between the superior articular process and the exiting nerve root, height of the intervertebral disc, height of the bulging disc, height of the intervertebral foramen, and distance from the insertion site to the spinous process on magnetic resonance imaging (MRI) and computed tomography (CT) scans of the lumbar spine. Logistic regression analysis was performed to determine factors associated with the need for additional drugs. In all, 23 cases (20.4%) required additional intraoperative medications because of hypertension, hypotension, bradycardia, or pain. Logistic regression analysis revealed that age (partial regression coefficient 0.05, p = 0.02) and bulging disc height (partial regression coefficient -0.7, p = 0.003) influenced the need for additional drugs. There were significant associations of need for additional intravenous medication with older age (>62 years) and a smaller bulging disc height (<8.2 mm). Patients with these factors require close monitoring for changes in vital signs or increasing pain when performing TELD under local anesthesia and may need additional intravenous medication.


Bone Formation During Correction of Vertebral Rounding Deformity in a Rat Model of Pediatric Spondylolisthesis.

Correction of vertebral rounding deformity was associated with improvement of chondrocyte differentiation; furthermore, there is possible involvement of a third mechanism, namely transchondroid bone ossification.Level of Evidence: N/A.


Return to the Original Work Activity Following the Full-endoscopic Lumbar Surgery under the Local Anesthesia.

Transforaminal full-endoscopic spine (TF-FES) surgery is minimally invasive and can be performed under local anesthesia. Thus, it is expected that the patient can return to work (RTW) quickly. However, information in the literature regarding this is sparse. The purpose of this study is to review the timing of RTW after TF-FES surgery. This study involved 50 patients (14 women, 36 men; mean age 44.5 years, age range: 20-65 years) who underwent TF-FES surgery between January 2016 and April 2018. All the patients were active workers. Occupations varied widely (e.g., physician, nurse, helper, clerk, construction worker, chef, and schoolteacher). There were no surgery-related complications. Median time to RTW was 21 days. More than half of the patients could RTW within 21 days. In all, 12 cases (24%) could have RTW within 7 days. Occupations of 12 patients who achieved RTW within 7 days included physician, company owner, and restaurant owner, with 11 in the Light work, 1 was in the Medium work, and none in the Heavy work. All 12 had a quick RTW because their work was Light and they could not take prolonged sick leave. Prompt RTW is possible with TF-FES surgery. The biggest merit of TF-FES surgery is minimal invasiveness to the muscles of the back. Also, it can be performed under local anesthesia. Our findings reveal quicker RTW after surgery, depending on occupational type.


Extraosseous Signal Changes on Magnetic Resonance Imaging in Pediatric Patients with Early-Stage Lumbar Spondylolysis.

Purpose : To analyze extraosseous signal changes (ESCs) on magnetic resonance imaging (MRI) in pediatric patients with stress fractures occurring in the lamina. Methods : This study was a retrospective review of 69 consecutive pediatric patients with stress fractures occurring in the lamina. We analyzed MRI scans obtained at the first presentation. Results : We used mainly axial short tau inversion recovery images acquired through the pedicle of these 84 fracture sites to identify the ESCs. These were then divided into three groups: "invisible" when no ESC was detected, "periosteal" for ESC seen on only the dorsal side of the lamina, and "perimuscular" for ESC distinctly spread around / in the paravertebral muscles. In total, 78 (92.9%) fracture sites showed ESCs on the dorsal side of the lamina among which 72 ESCs were located on only the "dorsal" side, while 6 ESCs were on the ventral side against the transverse process. Conclusion : ESCs on MRI were detected in more than 90% of patients before stress fracture became apparent in the lamina, which was considered similar to findings of periosteal thickening / edema detected at the onset of stress fracture in long bone. J. Med. Invest. 68 : 136-139, February, 2021.

The Journal of Medical Investigation : JMI


A new surgical strategy for the intractable chronic low back pain due to type 1 Modic change using transforaminal full-endoscopic disc cleaning (FEDC) surgery under the local anesthesia : A case report and literature review.

It has been reported that Modic change of the lumbar spine endplate includes three types: i.e. . edema or inflammation for type 1, fatty marrow change for type 2 and sclerotic change for type 3. Basically, type 1 Modic change may be related to the chronic low back pain. There are two kinds of the treatment for the type 1 Modic change to heal the pain : the anti-inflammatory drugs, and intra-discal injection of steroid. When the inflammatory change would be intractable, surgical intervention is needed. The gold standard for the surgical intervention is the segmental fusion of the affected level. The fusion surgery may cause the adjacent degeneration ; thus, motion preservation surgery is better, if possible. Our department started the motion preservation full-endoscopic intradiscal debridement surgery for this pathology, since some of the type 1 Modic change may be chronic discitis by P. Acnes. In this paper, we describe the first patient of type 1 Modic change who was successfully treated by the full-endoscopic intra-discal debridement and drainage under the local anesthesia. We named this procedure as transforaminal full-endoscopic disc cleaning surgery (FEDC). Finally, pathology, conservative and surgical intervention of Modic change was discussed. J. Med. Invest. 68 : 1-5, February, 2021.


Early outcomes of transforaminal percutaneous endoscopic lumbar discectomy for high school athletes with herniated nucleus pulposus of the lumbar spine.

There are no reports in the literature on the clinical outcomes of percutaneous endoscopic lumbar discectomy (PELD) for high school athletes suffering from herniated nucleus pulposus (HNP) of the lumbar spine. PELD is a minimally invasive surgical procedure that can be performed under local anesthesia via an 8-mm skin incision. This study examined the outcomes of transforaminal PELD in high school athletes suffering from HNP. Subjects were 18 patients [14 males and four females; mean age 17 (15-18) years] who underwent PELD at our institutions. The events in which the patients competed were baseball (n = 6), softball (n = 2), rugby (n = 2), basketball (n = 2), table tennis (n = 2), American football (n = 1), wrestling (n = 1), track and field (n = 1), and dance (n = 1). All patients underwent PELD under local anesthesia. Back pain was assessed using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) and a visual analog scale (VAS) before and after surgery. Time to return to competitive sport, complications, and rate of recurrence of herniation were examined. All factors assessed by the JOABPEQ were significantly improved after surgery. VAS score was also improved after surgery. Time to return to competitive sport was 7 weeks on average. The rate of return to play was 94.4%. There were no complications, such as dural tear, exiting nerve root injury, or hematoma. One patient had recurrence of HNP. PELD is a promising minimally invasive and effective procedure for high school athletes with HNP.

Journal of Pediatric Orthopaedics. Part B


Full-endoscopic Decompression of Foraminal Stenosis Caused by Facet Hypertrophy Contralateral to the Dominant Hand in a Baseball Pitcher: A Case Report.

Back pain and lower extremity pain have various causes and occasionally occur simultaneously, creating diagnostic difficulties. In addition, athletes require special consideration in terms of treatment. Here, we report a case of foraminal stenosis as a result of lumbar disc prolapse combined with facet hypertrophy contralateral to the dominant hand in a baseball pitcher that was successfully treated by minimally invasive full-endoscopic surgery. A 31-year-old left-handed male baseball pitcher presented with complaints of low back pain and right buttock pain while pitching. A diagnosis of foraminal stenosis caused by a disc bulge combined with facet hypertrophy contralateral to the dominant hand was made on the basis of physical and radiological findings. His symptoms improved immediately after transforaminal full-endoscopic lumbar discectomy and foraminoplasty under local anesthesia. He returned to play 3 months after surgery. Foraminal stenosis due to facet hypertrophy may occur in the side contralateral to the throwing arm in pitchers. Minimally invasive decompression using a full-endoscopic procedure is required for high-level athletes at this position.


Spontaneous Laminar Fracture during Successful Conservative Treatment of Lumbar Spondylolysis at the Adjacent Spinal Level: A Case Report.

Although lumbar spondylolysis (LS) is regarded as a stress fracture, the underlying pathomechanism has yet to be fully elucidated. Here, we present a case that casts doubt on the notion that LS is truly a stress fracture. An 11-year-old female basketball player was brought to our clinic with a 2-week history of persistent low back pain. Magnetic resonance imaging with short TI inversion recovery (STIR-MRI) showed high signal intensity changes at the L4 pedicles bilaterally. Computed tomography (CT) revealed a faint fracture line at the left pars interarticularis. We made a diagnosis of stress fracture and recommended conservative treatment, including cessation of sports activities and wearing of a hard brace. Compliance with treatment was excellent. As expected, the STIR-MRI findings at L4 gradually resolved and bone healing was achieved. However, a follow-up STIR-MRI scan 10 weeks later revealed high signal intensity at the left L5 pedicle. Conservative treatment was continued for the findings at L5, which were considered to indicate a stress fracture (spondylolysis). Five weeks later, CT revealed a bony defect in the lamina at L5 on the left and bone union at L4. Although LS is generally considered to be a stress fracture, there have been several reports of familial occurrence and genetic predisposition. This patient's mother had also been treated for spondylolysis at L5. These observations suggest an underlying genetic etiology in this case.


Morphometric Analysis of Subaxial Cervical Spine with Myelopathy: A Comparison with the Normal Population.

The morphometry of the sagittal diameter of the spinal canal, sagittal-transverse ratio, and canal-body ratio on axial reconstructive CT images appears useful for distinguishing cervical spinal canal stenosis involving myelopathy.


Surgical management of stress fracture of the contralateral pedicle in a baseball player with unilateral lumbar spondylolysis : A case report.

We describe successful surgical treatment in a case of L5 unilateral spondylolysis with contralateral pedicle stress fracture that was not resolved by conservative treatment in a high-performing college baseball player. The 20-year-old man presented with left low back pain that stopped his sports activities. Over the previous year, he had experienced a couple of episodes of pain that subsided with cessation of sports but reappeared after a return to sports. Computed tomography and magnetic resonance imaging revealed a right terminal stage pars fracture and a left pedicle stress fracture at L5. The pain originated from the left pedicle fracture, with no pain from the right unilateral spondylolysis. Given that conservative treatment for 1 year had not been effective, we decided on surgical treatment. Bilateral pedicle screws and the smiley face rod method were applied, and both fractures subsequently healed. In the 2 years since the surgery, the patient has returned to sports and has the potential to become a professional player. J. Med. Invest. 67 : 382-385, August, 2020.


Debridement for Infectious Spondylodiscitis in a 9-year-old Girl Using Full-Endoscopic Discectomy System : a Case Report and literature review.

Objective : Infectious spondylodiscitis (IS) is rarely seen in healthy elementary school age children. Conservative treatment with antibiotics is usually preferable but sometimes fails because of the low identification rate of the pathogen by percutaneous needle biopsy. When surgical treatment is indicated, selecting the appropriate procedure is crucial in terms of invasiveness for such young children. Case report : We present the case of a 9-year-old otherwise healthy girl with IS who successfully underwent debridement and identification of the causative pathogen using full endoscopic discectomy (FED) system. Methicillin-susceptible Staphylococcus aureus was identified on several cultures of samples. Immediately after the surgery, the LBP was significantly decreased and the remittent fever resolved dramatically. At the 1-year follow-up, she had no symptoms and plain radiographs showed bony fusion. Conclusion : This is the first report on IS in elementary school-age children treated with the FED system. Debridement using this system could provide minimally invasive and effective curettage of the infected disc space and can be helpful in identifying the pathogen even for small children. J. Med. Invest. 67 : 351-354, August, 2020.


Successful full-endoscopic decompression surgery under local anesthesia for L5 radiculopathy caused by L5-Sforaminal stenosis and L4-5 lateral recess stenosis : A case report.

In this report, we presented a 65 year-old male case having right leg pain due to L5 radiculopathy. Based on the radiological examination including CT, MRI and radiculography, double crash impingement of L5 nerve root due to L4-5 lateral recess and L5-S foraminal stenosis was diagnosed. Because of the strong pain, he could not work anymore. His job was a general manager of big hospital, he needed to return to job as soon as possible. We decided to conduct the full-endoscopic decompression surgery of ventral facetectomy (FEVF) for L4-5 lateral recess stenosis and foraminoplasty (FELF) for L5-S foraminal stenosis. The technique can be done under the local anesthesia with only 8 mm skin incision; thus, it must be the least invasive spine surgery. Soon after the surgery, he could return to the original job as a general manager. In conclusion, the full-endoscopic decompression surgery for the spinal canal stenosis such as FELF and FEVF would be minimally invasive procedure and it enable patients the quick return to the original activity. J. Med. Invest. 67 : 192-196, February, 2020.

The Journal of Medical Investigation : JMI


Distribution of the Spinal Arteries in Adult Patients with Lumbar Spondylolysis.

INTRODUCTION : The pathology of lumbar spondylolysis is generally thought to begin with a stress fracture in adolescence. Stress fractures of the lower extremities occur in watershed areas with a poor vascular supply because of an inability to respond to stress and heal. This pathology has not been well researched in the lumbar spine. The aim of this study was to evaluate the distribution of the spinal arteries in patients with lumbar spondylolysis. METHODS : The extraosseous distribution of the arteries around the pars interarticularis was retrospectively investigated in 14 patients with colon cancer who underwent abdominal contrast-enhanced computed tomography (CE-CT) as part of a preoperative assessment at our hospital and were found to have spondylolysis at L5. RESULTS : All patients were found to have terminal-stage spondylolysis at L5 (1 unilateral, 13 bilateral). L5 segmental artery was absent in all cases. However, separate spinal arteries supplying the pars interarticularis at L5 were found above and below the transverse process at this level. CONCLUSION : All the patients had two separate arteries originating from the cranial and caudal sides that distributed to the superior and inferior articular processes, suggesting that the pars interarticularis is a posterior element containing a vascular watershed area. J. Med. Invest. 67 : 62-66, February, 2020.


Operating Costs of Full-endoscopic Lumbar Spine Surgery in Japan.

For full-endoscopic lumbar discectomy, operating costs are also important because expensive equipment are necessary. We surveyed the operating costs of surgical equipment necessary for full-endoscopic surgery together with surgical procedure reimbursement fees. A total of 295 cases of full-endoscopic surgery via a transforaminal approach were retrospectively analyzed. We calculated the frequency of damage and the unit purchase price of devices such as endoscopes, and surgical instruments such as grasping forceps for nucleotomy, high-speed drill bar, and bipolar forceps, and examined the operating costs in Japanese yen against the procedure fee per case. Endoscope breakage occurred seven times, and a payment of ¥760,000 was necessary for trade-in and purchase of a new endoscope. The total breakage number of grasping forceps was 58, and the purchase price per unit was ¥116,000. Therefore, a total of ¥12,020,000 was required for the 295 cases, and the calculated operating cost that accompanies equipment breakage was ¥40,000 per case. In addition, about ¥118,000 was required for disposable bipolar forceps and high-speed drill bar to be used intraoperatively for each case. Thus, for one case it is calculated that total ¥158,000 is utilized for equipment from the surgical reimbursement fee per case specified by the Japanese Ministry of Health being ¥303,900. Minimally invasive procedures provide great benefit to patients; however, the eventual contribution to hospital profits is small and may not be sufficient. To resolve this issue, the cost of surgical equipment should be lowered and/or the surgical reimbursement fee of the full-endoscopic surgery should be raised.


Early return to activity after minimally invasive full endoscopic decompression surgery in medical doctors.

Full endoscopic surgery including discectomy (FED) and ventral facetectomy (FEVF) is a minimally invasive lumbar decompression surgery that only requires an 8 mm skin incision and can be done under the local anesthesia and sedation. Six male medical doctors underwent the endoscopic decompression (FED/FEVF) for common degenerative lumbar spine problems. Their age ranged from 27 to 63 years of age with a mean of 40 years. Five doctors underwent FED surgery for herniated nucleus pulposus (HNP), and the remaining one physician had FEVF for lumbar lateral recess stenosis. There were no surgery related complications. Postoperatively, 5 out of the 6 physician patients returned the original job within a week because they had clinical duties. The shortest duration to return to work was reported by a 63-year-old orthopedic surgeon resumed working in his clinic 2 days after the FEVF surgery. The longest duration to return to work occurred in general medicine resident who took almost 2 weeks for the sick leave because he did not have clinical duties. The mean duration for the returning to work was 5.8 days after the surgery. At final follow-up ranging from 6 to 30 months, all physician patients were working without any residual pain. In the hands of the authors, the full endoscopic transforaminal decompression surgery is the preferred surgical option and allowed early return to work-an observation that is not the norm in Japan.


Intracanalicular Osteochondroma in the Lumbar Spine.

resection of the osteochondroma with the ligamentum flavum relieved the symptoms. Spinal osteochondroma occurs relatively frequently in elderly individuals compared with peripheral lesions and mimics a degenerative spinal disorder. Careful physical examination and imaging evaluation can reveal this tumor and surgery is effective for relieving the symptoms.


Imaging Features of Non-Isthmic Spondylolysis: A Case Report.


What Type of Orthosis is Optimal for Conservative Treatment of Lumbar Spondylolysis?: A Biomechanical Analysis.

HO showed high restriction in all directions. RS showed higher restriction in extension than NB and less restriction in flexion and side bending than other custom-made LSOs. DC was the only soft LSO showing higher restriction than NB in flexion.


Transforaminal full-endoscopic lumbar discectomy under local anesthesia in awake and aware conditions: the inside-out and outside-in techniques.

Initially, TELD was performed as the "inside-out" technique but was associated with reports of postoperative dysesthesia due to exiting nerve injury. Recently, the "outside-in" technique after foraminoplasty was proposed for safer insertion of the cannula into the disc. Foraminoplasty can widen the narrow foramen, thereby allowing the 8-mm cannula to pass through easily and safely, and thus injury to the exiting nerve root can be theoretically avoided. We described two types of the TELD in this review. Surgeons should be familiar with the inside-out and outside-in techniques for TELD; therefore, we can select appropriate technique for each case.

Current Reviews in Musculoskeletal Medicine


Multiple Loose Bodies in the Lumbar Facet Joint: Case Report.

We describe here a patient diagnosed with multiple loose bodies in the lumbar facet joint. The patient was a 52-year-old woman who presented with left sciatic pain. Neurological findings indicated L5 radiculopathy. Radiological findings revealed lateral recess stenosis at the L4-L5 level, and loose bodies in the left L4-L5 facet joint were noted that compressed the left L5 nerve root. We performed laminotomy at the left L4-L5 level, and removed five loose bodies located on the dorsal side of the ligamentum flavum. Following removal of the loose bodies and flavectomy, the L5 nerve root was decompressed. Postoperatively, the patient's symptoms improved markedly. Symptomatic multiple loose bodies in the lumbar facet joint are very rare, and can cause lumbar radiculopathy. It is important for spine surgeons to recognize this pathology.


A Rare Case of Acute-Onset Spastic Quadriparesis Caused by a Chondroma of the Cervical Spine.

Chondromas are benign cartilaginous tumors that occur very rarely in the spine. Moreover, chondromas of the extraskeletal origin are also very rare. In this case report, we describe an extremely rare case of chondroma arising from the ligamentum flavum in the cervical spine. A 67-year-old man presented to our clinic with acute-onset spastic quadriparesis. We performed emergent magnetic resonance imaging and found an epidural mass in the right ligamentum flavum at C4-C5. The acute-onset presentation was suspicious for intraligamentous hematoma in the ligamentum flavum at this level. We performed emergency decompression surgery and en bloc removal of the epidural mass with the right C4 and C5 lamina. The lesion had the appearance of cartilaginous tissue rather than hematoma. Based on the histological investigation, the final diagnosis was intraligamentous chondroma of the cervical spine. The quadriparesis improved postoperatively, as did the results of manual muscle testing in the affected area, and he was able to resume walking independently with a cane. At the one-year follow-up, the manual muscle testing results were almost normal. Surgeons should keep in mind the possibility of benign tumors including chondroma of the cervical spine when a patient presents with acute-onset quadriparesis.


Ⅱ各種疾患に対する治療法・モダリティ 腰部脊柱管狭窄症に対する局所麻酔下の全内視鏡手術

整形・災害外科 4月臨時増刊号 脊椎脊髄外科の最近の進歩

整形・災害外科 4月臨時増刊号 脊椎脊髄外科の最近の進歩


Low Back Pain in Adolescent Athletes: Comparison of Diagnoses Made by General Orthopedic Surgeons and Spine Surgeons.

In adolescent athletes, the rate of NSLBP diagnosed by general orthopedic surgeons decreased markedly when the diagnosis was made by spine surgeons. A thorough medical interview, careful physical examination, appropriate diagnostic imaging, and selective nerve block examination can effectively identify the cause of low back pain.


Identification of abnormalities in the lumbar nerve tract using diffusion-weighted magnetic resonance neurography.

Abnormalities of the lumbar nerve tract caused by congenital variations or high nerve root take-off angles are difficult to visualize. Diffusion-weighted magnetic resonance neurography (DW-MRN) has recently been introduced for imaging of the lumbosacral region. The aims of this study were to identify lumbar nerve tract abnormalities caused by congenital variation or a high nerve root take-off angle using DW-MRN and to assess the diagnostic value of this imaging modality.

Congenital variations were identified in 8 patients (9 nerve roots, 1.6%). The most commonly identified variation was in the sacral nerve root (n = 5) followed by the L4 (n = 3) and L5 (n = 1) nerve roots. All variations identified were on the left side. There were 3 cases of type 1a variation, 1 of type 1b, 1 of type 2, and 4 of type 3. In total, 210 (36.6%) of the magnetic resonance images showed high nerve root take-off angles at the intervertebral foramen that was caused by disk herniation, spondylolisthesis, or osteophytes with degeneration. Patients with high nerve root take-off angles were significantly older than those without (P < 0.05). These slides can be retrieved under Electronic Supplementary Material.


Thermal Annuloplasty Using Percutaneous Endoscopic Discectomy for Elite Athletes with Discogenic Low Back Pain.

The purpose of this study was to assess the usefulness of radiofrequency thermal annuloplasty (TA) using percutaneous endoscopic discectomy/TA (PED/TA) in elite athletes with discogenic low back pain. Twelve patients (11 men, 1 woman; mean age 27.9 years) underwent PED/TA under local anesthesia. Clinical data for these patients (17 affected intervertebral discs), including type of sport played, average duration of low back pain, disc level affected, presence or absence of a high signal intensity zone on magnetic resonance imaging, and whether the patient returned to playing competitive sport, were retrospectively reviewed. The most common sport played by the patient was baseball (n = 8), followed by cycling (n = 2), tennis (n = 1), and hammer throw (n = 1). The average duration of low back pain was 24.3 months. The intervertebral disc levels affected were L4/5 (n = 11) and L5/S1 (n = 6). A high signal intensity zone was detected in nine discs. Although two patients required additional surgery, all patients were able to return to their original competitive level of play. Duration for the return to play was 2.8 months after surgery except the two revision cases. PED/TA for discogenic pain enables an early return to competitive sports, and so is particularly useful for elite athletes.


Age-related changes in axial and sagittal orientation of the facet joints: Comparison with changes in degenerative spondylolisthesis.

Despite facet joints being three-dimensional structures, previous computed tomography and magnetic resonance imaging studies have evaluated facet joint orientation in only the axial plane. Facet joint orientation in the sagittal plane has rarely been studied using these imaging techniques. The aim of this study was to elucidate facet joint orientation in both the axial and sagittal planes on computed tomography. A total of 568 patients (343 men, 225 women) (excluding orthopedic outpatients) for whom abdominal and pelvic computed tomography scans were obtained at our hospital between September 2010 and October 2012 were included. Mean age was 63 (range 21-90) years. Patients were divided into a degenerative spondylolisthesis group (67 patients; 30 men, 37 women) and a control group (313 patients; 313 men, 188 women). Facet joint orientation was evaluated in the control group according to patient age (≤50, 51-60, 61-70, or ≥71 years). The findings in the control group were then compared with those in the degenerative spondylolisthesis group. The orientation of the lumbar facet joints at each level was measured in the axial and sagittal planes on computed tomography images. Facet joint angles decreased with age at L4/5 and L5/S1 in women in the axial plane and at L4/5 in men and L3/4 and L4/5 in women in the sagittal plane. The variation in facet joint angle was greatest at L4/5 in women. Patients with degenerative spondylolisthesis showed more sagittally and horizontally oriented facet joints in the axial and sagittal planes; facet tropism showed an association with degenerative spondylolisthesis in the axial plane. The axial and sagittal orientation of facet joints in the lower lumbar vertebra, especially L4/5, was negatively correlated with age. This finding could help to explain why older people are more prone to degenerative spondylolisthesis.


Spontaneous lumbar spinal subdural hematoma: a case report.

Spinal subdural hematoma (SSDH) is an uncommon disease causing acute onset of spinal disorder. Several causes of SSDH have been reported, but reports of spontaneous occurrence of SSDH are limited.


Surgical Treatment of Lumbar Herniated Nucleus Pulposus Combined with Residual Bony Fragment of Apophyseal Ring Fracture in High-Level Athletes : A Report of Two Cases.

In this paper, we present 2 cases of herniated nucleus pulposus (HNP) combined with the residual bony fragment of apophyseal ring fracture. HNP typically exists at the narrow lateral recess formed by the bony fragment, and so it has been reported that symptoms may persist. Case 1 was a 22-year-old man, a high-level javelin thrower and Paralympic athlete. He had a history of persistent pain for 4 years due to HNP, and so we performed surgical removal. Case 2 was a 23-year-old male professional baseball player. He was referred to us only 17 days after the onset of pain and presented with muscle weakness, a feature which may prolong the clinical course in addition other features such as pain. Thus, we performed a comparatively quick intervention of surgical removal. In both cases, we had excellent clinical outcomes and better function and performance. In conclusion, in cases with HNP and apophyseal ring separation, surgical intervention in the comparatively early phase can be recommended, particularly if the patients desire quick return to their original level of activity. J. Med. Invest. 66 : 358-361, August, 2019.

The Journal of Medical Investigation : JMI


Minimally invasive cervical micro-endoscopic foraminotomy for C6 radiculopathy with overlooked scapular winging - A case report.

A 73-year-old woman complained of right medial side of scapular pain associated with winged scapula to miss without observing the back in minute detail. Additional treatment was required due to overlooking caused by insufficient examination. We performed micro-endoscopic foraminotomy that provided the disappearance of scapular pain and improvement of winged scapula in relatively early. It was commonly said that winged scapula is an extremely rare condition that causes dysfunction of the upper extremities. We suggest that there are the meaning of winged scapula in diagnosis and the importance of physical examination. Further studies should be required to research the morbidity of winged scapula associated with cervical disease. By sharing our experience of this attention arousing case, we provide information not to repeat the same mistakes. J. Med. Invest. 66 : 340-343, August, 2019.


A semi-rigid thoracolumbar orthosis fitted immediately after spinal surgery : stabilizing effects and patient satisfaction.

Purpose : To evaluate the stabilizing effects of a Fit Cure-Spine® semi-rigid thoracolumbar orthosis and wearer satisfaction after lumbar surgery. Methods : In study 1, the spinal angle, spinal motion angle, and distribution of load were measured in 8 adult male volunteers when the orthosis was worn (1) with no custom-made stay (CMS), (2) with a CMS in the prone position (P-CMS), and (3) with a CMS in the prone position and decreased lordosis (DP-CMS). In study 2, pain scale scores and responses to a questionnaire were recorded in 40 consecutive patients who underwent lumbar spinal surgery in our hospital. Results : In study 1, the mean lumbar lordosis when standing was similar to that in the prone position. When the trunk was bent forward, loads on the back support in P-CMS and DP-CMS were concentrated at the center of the CMS, unlike those for No-CMS. In study 2, there was a significant decrease in postoperative wound pain after wearing the Fit Cure-Spine orthosis for 2 weeks. Most patients who wore the orthosis were satisfied with their pain outcome. Conclusion : Adjustment to lumbar lordosis and the prone position was restricted in volunteers wearing the Fit Cure-Spine with a CMS. J. Med. Invest. 66 : 275-279, August, 2019.


Accurate diagnosis of low back pain in adult elite athletes.

Background : There is few reports evaluated accurately the pain generator of low back pain in elite athletes. The purpose of this report was to show case series and to investigate the cause of unidentified low back pain of elite athletes. Methods : Twenty-three adult elite athletes consulted our sports spine clinic to seek a second opinion for low back pain between April 2013 and March 2016. Their cause of low back pain had not been identified by nearby doctor. Spine surgeons had diagnosed using diagnostic injection and STIR-MRI and the final diagnosis made by the spine surgeon were collected. Results : The mean age of 23 patients (16 male, 7 female) was 30.4 years. The most common sport played was baseball. The final diagnosis made by a spine surgeon was as follows : disc related low back pain (n = 12), facet joint arthritis (n = 5), vertebral endplate injury (n = 4), early-stage lumbar spondylolysis (n = 1), supraspinous ligament injury (n = 1). Conclusions : A thorough medical interview, careful physical examination, appropriate diagnostic imaging, and injection block examination can effectively identify the cause of low back pain. J. Med. Invest. 66 : 252-257, August, 2019.


A novel surgical concept of transforaminal full-endoscopic lumbar undercutting laminectomy (TE-LUL) for central canal stenosis of the lumbar spine with local anesthesia : A case report and literature review.

Full-endoscopic spinal surgery was first developed for the lumbar herniated nucleus pulposus. Mainly, there are two types in the full-endoscopic lumbar surgery : i.e., transforaminal (TF) and interlaminar approach. The surgery can be done under the local anesthesia for the TF approach ; therefore, we need to further develop the TF approach to variety of the spinal disorders. Recently, the TF full-endoscopic surgery has been applied for the spinal canal stenosis. First, transforaminal full-endoscopic lumbar foraminoplasty for the foraminal stenosis ; then, transforaminal lumbar lateral recess decompression for the lateral recess stenosis has been developed. Finally, we have developed the surgical technique to decompress the central stenosis via TF approach under the local anesthesia. Prior to initiate the clinical case, we have attempted the lumbar undercutting laminectomy using a fresh cadaveric spine. After we technically confirmed that the transforaminal full-endoscopic lumbar undercutting laminectomy (TE-LUL) is possible, we applied the technique to the patient whose lung capacity did not allow general anesthesia. The 72 years old female patient with central canal stenosis could be improved her left leg pain and muscle weakness after TE-LUL under the local anesthesia. In this paper, we introduce the surgical technique of the TE-LUL and discuss of the efficacy of the TE-LUL. J. Med. Invest. 66 : 224-229, August, 2019.


Radiological Outcomes of Posterior Lumbar Interbody Fusion Using a Titanium-coated PEEK Cage.

INTRODUCTION Titanium (Ti) coated polyether ether ketone (PEEK) interbody cages (IBCs) have been introduced to overcome any disadvantages. The purpose of this study was to investigate the radiological outcomes of lumbar interbody fusion (LIF) surgery using the Ti-coated PEEK IBC with a minimum of 1-year of follow-up. METHODS A total of 26 intervertebral spaces in consecutive 21 patients who underwent posterior/transforaminal LIF using the Ti-coated PEEK IBC were evaluated. Rates of bone union, screw loosening, cage subsidence and bone cyst formation around the endplate were evaluated on computed tomography scans acquired at least 1 year postoperatively. RESULTS AND DISCUSSION At the 1-year follow-up, bone fusion was achieved in 23 (88.4%) of 26 intervertebral spaces. Cagesubsidence was found in 5 intervertebral spaces ; however,bone fusion was achieved in all these spaces. Bone cysts formed in 4 intervertebral spaces and 4 of 94 screws were found to be loosened. Three of the loosened screws were found in vertebral bodies adjacent to intervertebral spaces with nonunion. However, there was no association between these events. Although more scientific evidence is required to determine the advantages of Ti-coated PEEK IBCs, we believe the clinical outcomes achieved were favorable at the 1 year minimum follow-up. J. Med. Invest. 66 : 119-122, February, 2019.


An Adolescent Athlete with Low Back Pain Associated with Spina Bifida Occulta at the Thoracolumbar Junction : A Case Report.

These results suggest that evaluation of the coordination of the muscles and skeletal structures has an important role in the treatment of cases with an anatomical abnormality such as SBO. J.Med.Invest.66:199-200, February, 2019.


Successful Endoscopic Surgery for L5 Radiculopathy Caused by Far-Lateral Disc Herniation at L5-S1 and L5 Isthmic Grade 2 Spondylolisthesis in a Professional Baseball Player.

Minimally invasive endoscopic surgery is an option for radiculopathy in very active patients who need an early return to their previous level of physical activity.


Kinematically and kinetically, the spinopelvic angles in Dash were considered similar to those in Shoot. Dash could cause mechanical stress at the pars interarticularis of the lumbar spine, similar to that caused by Shoot, thus leading to spondylolysis.


Bony Healing of Discontinuous Laminar Stress Fractures Due to Contralateral Pars Defect or Spina Bifida Occulta.

Contralateral pars defect remains an unfavorable factor for bony healing discontinuous laminar stress fractures.


A New Method of Image Evaluation for Diagnosis of Pain : Clinical Application of Diffusion-weighted Imaging

痛み診断の新規画像評価 : 特に拡散強調画像の臨床応用について (日本腰痛学会 特集号) -- (特集 腰痛治療の革新 : 慢性腰痛・神経障害性疼痛に対する治療のbreakthrough)


Vertebral Lateral Notch as Optimal Entry Point for Lateral Mass Screwing Using Modified Roy-Camille Technique.

The vertebral lateral notch of the cervical spine was an effective landmark to determine the entry point for lateral mass screwing. The modified Roy-Camille technique proposed here may prevent surgical complications and poor outcomes.


Physical features of pediatric patients with lumbar spondylolysis and effectiveness of rehabilitation.

The purpose of this study was to evaluate the physical features of pediatric patients with lumbar spondylolysis (LS), factors that increase the load during compensatory movements at the lumbar spine, and the outcomes of rehabilitation. Twenty patients were included. Fifteen items were used:fingertip-to-floor distance (FFD), straight leg raising (SLR), heel-to-buttock distance (HBD), tightness of the rectus femoris, the lateral and medial rotator muscles, iliopsoas, tensor fascia lata, adductor muscles, soleus muscle, and latissimus dorsi, and trunk rotation, sit-ups and endurance of the abdominal and back muscles. Initial findings were judged as positive or negative using previously reported cut-off values and were re-evaluated 2 or 3 months later. Positive tests were found for HBD and tightness of the rectus femoris in 85% of the patients, for endurance of the abdominal muscles in 75%, SLR and sit-ups in 70%, and FFD and tightness of the external rotator muscles in 60%. The physical features varied according to the type of sport played, and some patients were refractory to rehabilitation. Only 17.6%, 33.3%, and 40.0% of patients with initially positive findings for HBD, tightness of the external rotator muscles, and endurance of the abdominal muscles, respectively, achieved improvements after rehabilitation. J. Med. Invest. 65:177-183, August, 2018.

The Journal of Medical Investigation : JMI


Role of Epiligament in Ligamentum Flavum Hypertrophy in Patients with Lumbar Spinal Canal Stenosis:a Pilot Study.

Ligamentum flavum (LF) hypertrophy is one of the main factors of lumbar spinal canal stenosis (LSCS). The primary object of this study is to clarify the existence of epiligament in the LF and its role in hypertrophy, and to develop an LF hypertrophy animal model. A cadaveric spine from a 30-year-old man was used to investigate the existence of epiligament in LF. Five LF samples from LSCS patients were obtained to evaluate hypertrophied LF. To create a rat model, we destabilized the lumbar spine. Each LF was sagittally cut for histological evaluation. The epiligament was clearly evident in normal LF specimens, which stained pink on Elastica van Gieson and green on Masson Trichrome. One layer was observed on the dural side and another on the dorsal side of the LF. LSCS patients had an enlarged dorsal epiligament, at around 30 times that of the regular thin epiligament on the dural side. The destabilized rat model showed an enlarged dorsal epiligament, with a mean thickness 8-fold that of the control. LF hypertrophy may be due to enlargement of the dorsal epiligament. Mechanical loading of the LF is an important factor for inducing hypertrophy in the rat model. J. Med. Invest. 65:85-89, February, 2018.


Utility of STIR-MRI in Detecting the Pain Generator in Asymmetric Bilateral Pars Fracture: A Report of 5 Cases.

Lumbar spondylolysis usually occurs as a stress fracture in the pars interarticularis of the vertebra. It is a prevalent sports-related disorder and a common cause of low back pain. We encountered five athletes (4 males, 1 female) with severe low back pain. Mean age was 14.5 years. All five patients were found to have bilateral pars fracture. In all cases, staging based on the findings from computed tomography scan of the right and left pars fracture was different. On short tau inversion recovery magnetic resonance imaging (STIR-MRI) of the comparatively newer more recently injured side, high signal intensity changes were obvious and dominant at the intra- and extraosseous area, which would indicate tissue edema and/or bleeding. Furthermore, the imaging findings corresponded to the side of the low back pain. In conclusion, STIR-MRI can effectively distinguish between painful pars fracture and painless pars fracture.


Bone Bruise of the Thoracic Spine Caused by Mild Physical Activity in Children.

Vertebral bone bruise (VBB) in children commonly occurs following a fall from a height, and more than one vertebral body may be affected. We encountered 6 children each with a single VBB caused by mild physical activity. All the children had tenderness on the corresponding spinous process with no neurologic findings. Magnetic resonance imaging (MRI) showed typical findings of VBB in all cases. The children were treated conservatively with a soft thoracolumbar brace and instructed to rest with no physical activity for a month. At follow-up 1 month later, the back pain had diminished, and the signal changes seen on MRI had disappeared in all cases. We conclude that mild physical activity may be a cause of VBB in children and good clinical results can be achieved by using a soft thoracolumbar brace and rest.


Magnetic resonance imaging and diffusion-weighted imaging findings in posterior spinal cord infarction: Case report.


Study of lesions of the lumbar endplate based on the stage of maturation of the lumbar vertebral body: the relationship between skeletal maturity and chronological age.

The lesion of the lumbar endplate is sometimes identified in the vertebrae of children and adolescents. The purpose of this study is to compare between skeletal maturity and chronological age. The second purpose of this study is to clarify the lesions of the lumbar endplate based on the maturation of the lumbar vertebral body. Six hundred and thirty-two (485 men and 147 women) consecutive patients were included. The mean age at the first medical examination was 13.8 years. Their skeletal maturity was evaluated based on the appearances of the secondary ossification center of L3. The area of the endplate lesions was classified into five types. The apophyseal stage was observed from 10 years old to 18 years old, and the apophyseal stage was shown the peak at 14 years old. The appearance of the apophyseal ring was observed earlier in female patients than in male patients. For the concave type, the lesion at upper level vertebra was more prevalent. The anterior and middle type of the lesion at upper level vertebra was more prevalent. For the posterior type, the lesion of the inferior rim of L4 and the lesion of the rim of L5 were more prevalent. This study emerged after comparing skeletal maturity based on the maturation of the lumbar vertebral body with the chronological age of a large number of patients and examining the lesions of the lumbar endplate based on the stage of maturation of the lumbar vertebral body.

European Journal of Orthopaedic Surgery & Traumatology


Pediatric isthmic spondylolisthesis showing radiologic evidence of slippage after physis injury.

The pathogenesis of slippage in pediatric spondylolisthesis is still unclear, although epiphyseal injury may account for many cases based on preclinical studies. However, no reports have described a pediatric case of isthmic spondylolisthesis showing radiologic evidence of epiphyseal injury. We report such evidence in a 13-year-old boy with low-back pain. Radiography revealed rounding of the S1 surface, a fracture line below the S1 endplate surface, and a bone marrow lesion in addition to slippage. Slippage and the rounding deformity were partially reversed (from 20 to 14% and from 42 to 27%, respectively) with conservative treatment and natural bone remodeling.

Journal of Pediatric Orthopaedics. Part B


Degenerative Changes of the Facet Joints in Adults with Lumbar Spondylolysis.

Degenerative changes of the facet joints in patients with lumbar spondylolysis were more severe than those without spondylolysis.


Anatomical considerations of the iliac crest on percutaneous endoscopic discectomy using a transforaminal approach.

From the results of this study, the trajectory of TF-PED can be limited by the surrounding anatomical structures. The maximum inclination angle indicated that treatment for the central type of LDH at the L5-S1 disc level was considered more difficult than that at the L4-L5 disc level because of the iliac crest. In the clinical setting, such anatomical particularities can be overcome by using a more perpendicular approach (hand-down technique) with the possible addition of a foraminoplasty. Moreover, we found that we must consider the laterality of the trajectory of TF-PED in terms of the patients' age or sex.

Percutaneous endoscopic discectomy is a minimally invasive procedure for the surgical treatment of lumbar disc herniation (LDH). It can be performed under local anesthesia and requires a skin incision of only 8 mm, with minimal disruption of the spinal structures including ligaments and muscles. However, performing percutaneous endoscopic discectomy with a transforaminal approach (TF-PED) for the lower lumbar spine is associated with some anatomical problems, such as interference from the iliac crest. This study sought to assess the operability of TF-PED for the lower lumbar spine.


Conservative Treatment for Bony Healing in Pediatric Lumbar Spondylolysis.


Pediatric Patient with Incidental Os Odontoideum Safely Treated with Posterior Fixation Using Rod-Hook System and Preoperative Planning Using 3D Printer: A Case Report.

Os odontoideum is often found incidentally. Surgical treatment is recommended for patients with atlantoaxial instability or neurologic deficits. Although various techniques have been used for C1-C2 fusion in adults, the use of these procedures in children is not widely accepted. We present a 12-year-old boy with incidental os odontoideum and obvious C1-C2 instability, in which bony union was achieved safely and successfully by posterior fixation using a rod-hook system and perioperative planning using a three-dimensional printer. At the 2-year follow-up, bone formation around the gap of the dens, which has been generally considered as pseudoarthrosis, was obtained after union of the posterior element of C1-C2.

Journal of Neurological Surgery. Part A, Central European Neurosurgery


Answer to the Letter to the Editor of C. Birkenmaier concerning "Rehydration of a degenerated disc on MRI synchronized with transition of Modic changes following stand-alone XLIF" by K. Kita, T. Sakai, M. Abe, Y. Takata and K. Sairyo (Eur Spine J; 2017). doi:10.1007/s00586-017-4945-6.


Etiology of Adult-onset Stress Fracture in the Lumbar Spine.

Although lumbar spondylolysis is generally recognized to occur in childhood or adolescence, fresh lumbar spondylolysis should be included in the differential diagnosis of adult low back pain when patients are high-level athletes. Conservative treatment should be attempted for adult patients.


Radiation Exposure to the Hand of a Spinal Interventionalist during Fluoroscopically Guided Procedures.

Our findings indicated that the cumulative radiation dose measured at the dominant hand may exceed the annual dose limit specified by the International Commission on Radiological Protection. Spinal interventionalists should take special care to limit the duration of fluoroscopy and radiation exposure.


Surgical Removal of Circumferentially Leaked Polymethyl Methacrylate in the Epidural Space of the Thoracic Spine after Percutaneous Vertebroplasty.

Background The major complication of percutaneous vertebroplasty (PVP) using polymethyl methacrylate (PMMA) is epidural leakage of PMMA that damages the spinal cord. Methods This is a case report. Result A 77-year-old man presented to our institution with a 6-month history of muscle weakness and an intolerable burning sensation of both lower limbs after PVP with PMMA for thoracic compression fracture at T7 at another hospital. His past medical history was significant for hypertension. He had no history of smoking and alcohol. Computed tomography revealed massive leakage of PMMA into the T6 and T7 spinal canal circumferentially surrounding the spinal cord that caused marked encroachment of the thecal sac. Magnetic resonance images revealed cord compression and intramedullary signal change from T6 to T7 level. After we verified that the leaked PMMA could be easily detached from the dura mater in the cadaveric lumbar spine, surgical decompression and removal of epidural PMMA was performed. The leaked PMMA was carefully thinned down with a high-speed diamond burr. Eight pieces of PMMA were detached from the dura mater easily without causing a dural tear. No neurologic deterioration was observed in the postoperative period. The burning sensation resolved, but the muscle weakness remained unchanged. One and a half years postoperatively, the muscle weakness has improved to ⅘ on the manual muscle strength test, but he could not walk without an aid because of spasticity. Conclusion This report demonstrates the catastrophic epidural extrusion of PMMA following PVP. Extravasated PMMA can be removed through a working space created by means of laminectomy and subtraction of the affected pedicle. Spine surgeons should recognize the possible neurologic complications of PVP and be prepared to treat them using suitable approaches.


Rehydration of a degenerated disc on MRI synchronized with transition of Modic changes following stand-alone XLIF.

Lumbar intervertebral disc degeneration (LDD) is known to be associated with low back pain (LBP) and leads to degenerative lumbar disease. LDD is considered to be irreversible, and no truly effective treatment that suppresses LDD or regenerates the degenerated disc has been established thus far. Here, we report the case of a 42-year-old woman with a 10-year history of persistent LBP. Magnetic resonance imaging (MRI) demonstrated degenerative changes (Pfirrmann classification: grade IV) in the L4-5 intervertebral disc with type I and III mixed Modic changes adjacent to the disc. Conservative treatments were not effective, so we opted for stand-alone extreme lateral interbody fusion (XLIF). One year after the operation, the LBP had almost disappeared. Follow-up MRI revealed transition of the Modic changes from type I to type III. In addition, rehydration of the degenerated disc behind the XLIF cage was evident (Pfirrmann classification changed from grade IV to grade II). To our knowledge, this is the first report of a change in LDD. Several factors are likely responsible for the regenerative response, including curettage of the hyaline cartilaginous endplates and auto-iliac cancellous bone grafting, which were considered to have affected nucleus pulposus cells in the residual disc.


Changes of posture and muscle activities in the trunk and legs during walking in patients with lumbar spinal stenosis after decompression surgery. A preliminary report.

Neurogenic intermittent claudication is a main symptom in lumbar spinal stenosis (LSS), and postural change is often observed during walking. This study aimed to identify the changes in posture and muscle activity in the trunk and legs during walking in patients with LSS by examining 6 patients who had undergone decompression surgery. None of them had significant paralysis. Gait analysis using Vicon motion capture system(®) with electromyographic recordings of the paravertebral muscles (PVM) and vastus lateralis muscle (VL) was performed preoperatively and 2 weeks postoperatively. Results showed that the thorax angle indicating the degree of trunk flexion after walking decreased significantly and the pelvic angle tended to decrease after surgery. However, there were no difference in the spine angle, which is a measure of the motion of the thoraco-lumbar spine among the evaluations. The knee angle increased significantly after surgery both at the beginning and at the end of walking, but the angles of the hip and ankle did not change significantly after surgery. Knee torques increased significantly after surgery both at the beginning and at the end of walking. The activity of the PVM decreased and that of the VL increased after surgery. The results indicate that patients with LSS walk in a forward-bending position without flexing the spine, which can be one of the neurologic symptoms. Increases in knee torque and VL activity seemed to reflect the increase of walking speed, and the decrease of PVM activity appeared to be caused by postural improvement after surgery.


Eight-year follow-up findings of surgical treatment for severe dystrophic changes in the cervical spine associated with neurofibromatosis type I: a case report.

Long-term follow-up findings for dystrophic changes in the cervical spine caused by neurofibromatosis type 1 have been rarely reported. A 13-year-old boy with severe dural ectasia in the cervical spine underwent cervical posterior fusion from C1 to C5 for prevention of cervical spine fracture and spinal injury. We followed him up for 8 years after surgery. We measured the progression of the destruction on yearly MRI. The dural ectasia gradually progressed until 3 years postoperatively. Subsequently, no further enlargement of the dural sac occurred. At the 8-year follow-up examination, the patient had no limitations in the activities of daily life.

Journal of Pediatric Orthopaedics. Part B


非特異的腰痛診断に陥りやすい椎間板性腰痛

非特異的腰痛診断に陥りやすい椎間板性腰痛

Japanese Journal of Orthopaedic Sports Medicine

日本整形外科スポーツ医学会雑誌


Signal intensity changes of the posterior elements of the lumbar spine in symptomatic adults.


The reduction and direct repair of isthmic spondylolisthesis using the smiley face rod method in adolescent athlete: Technical note.

Presently, lumbar spondylolisthesis did not have the indication of direct repair surgery because of the difficulty to reduce the slippage. In this report, we presented a case and described a minimally invasive direct repair surgery to reduce and repair the pars interarticularis defects of lumbar spondylolisthesis. First, curettage and removal of the synovium of the pars interarticularis and decompression of nerve root are conducted. Next, cancellous bone is harvested from the iliac crest. And then the Percutaneous Pedicle Screws are inserted bilaterally. A rod is bended and placed just caudal to the spinous process. We can make reposition of slipped vertebra and stabilize the loose lamina more firmly using a reduction tool and a rod pusher. Finally, bone grafts are implanted onto the pars defects. The Smiley face rod method is very useful to reduce the slippage and repair the pars defects in the lumbar spondylolisthesis especially in adolescent athletes. J. Med. Invest. 64: 168-172, February, 2017.

The Journal of Medical Investigation : JMI


Natural Correction and Adaptation of a Severely Deformed Sacral Dome in an Adolescent with Isthmic Spondylolisthesis: A Case Report.

Vertebral deformity in children can be reversible. Orthopaedic surgeons should be aware that pediatric patients with a severe deformity of the sacral dome and vertebral slippage can be managed nonoperatively.


Accurate diagnosis of chronic low back pain in a high-level college athlete: a case report.

A 21-year-old woman who was high-level college softball player presented with a 6-month history of low back pain that had been treated unsuccessfully by medication at local clinics. There was tenderness in the left paravertebral muscle at the lower lumbar level. X-ray and computed tomography revealed congenital scoliosis and an L6 hemivertebra. Short tau inversion recovery magnetic resonance imaging showed a fluid collection at the left L6-S1 facet joint. We performed a diagnostic facet injection, consisting of 1% lidocaine and steroids, that was infiltrated into the left facet joint at L6-S1. Her persistent low back pain disappeared immediately after the facet block. We diagnosed left-sided facet arthritis at L6-S1. Due to her multiple congenital anomalies, excessive loading occurred at the facet joint. Therefore, we opted for conservative management, including mobilization of the thoracic spine and stretching of hamstrings and quadriceps. This case report underscores the importance of accurate diagnosis of low back pain and of the diagnostic utility of short tau inversion recovery magnetic resonance imaging and lumbar facet block in young athletes with chronic spinal pain. J. Med. Invest. 64: 313-316, August, 2017.


Percutaneous full endoscopic lumbar foraminoplasty for adjacent level foraminal stenosis following vertebral intersegmental fusion in an awake and aware patient under local anesthesia: A case report.

Percutaneous endoscopic surgery for the lumbar spine has become established in the last decade. It requires only an 8 mm skin incision, causes minimal damage to the paravertebral muscles, and can be performed under local anesthesia. With the advent of improved equipment, in particular the high-speed surgical drill, the indications for percutaneous endoscopic surgery have expanded to include lumbar spinal canal stenosis. Transforaminal percutaneous endoscopic discectomy has been used to treat intervertebral stenosis. However, it has been reported that adjacent level disc degeneration and foraminal stenosis can occur following intervertebral segmental fusion. When this adjacent level pathology becomes symptomatic, additional fusion surgery is often needed. We performed minimally invasive percutaneous full endoscopic lumbar foraminoplasty in an awake and aware 50-year-old woman under local anesthesia. The procedure was successful with no complications. Her radiculopathy, including muscle weakness and leg pain due to impingement of the exiting nerve, improved after the surgery. J. Med. Invest. 64: 291-295, August, 2017.


Radiographic changes of cervical destructive spondyloarthropathy in long-term hemodialysis patients: A 9-year longitudinal observational study.

Analyses of radiographic changes and clinical symptom of destructive spondyloarthropathy (DSA) on consecutive 42 patients managed with long-term hemodialysis were performed to elucidate radiographic changes of DSA and the factors that influence to the destructive changes. Patients underwent plain radiographs of the cervical spine with 9 years interval. Grading of radiological feature from lateral view was classified into grade 0 to grade 3. Clinical symptom was evaluated using modified Japanese Orthopaedic Association scoring system for cervical myelopathy (mJOA score). Destructive changes were observed in 3 patients at the first examination, and those were observed in 15 patients 9 years after the first examination. There is no statistically significant difference between the duration of hemodialysis and the grade. The mean age at the onset of hemodialysis, however, was significantly higher in patients of grade 2 and 3 than those of grade 1. Older patients with long-term hemodialysis had destructive changes. Destructive changes commonly observed in lower cervical spine. The average numbers of the involved disc level were 1.6 in grade 2 and 1.0 in grade 3. Clinical symptoms were varied in each grade and there was no statistically significant difference in total mJOA score among these grades. J. Med. Invest. 64: 68-73, February, 2017.


High intensity zone in lumbar spine and its correlation with disc degeneration.

Purpose; To investigate the prevalence, clinical significance of high intensity zone (HIZ), and associated disc degeneration. Materials and methods; We undertook retrospective analysis of 228 patients, aged from 15 to 55 years, who had undergone magnetic resonance (MR) imaging of lumbar spine in outpatient clinic from 2013 to 2014. HIZ was defined as a presence of high intensity signal in the annulus on T2-weighted images. All HIZ positive discs were classified according to Pfirrmann grading system for presence of disc degeneration. Results; Forty-three patients (18.8%) with 53 intervertebral discs demonstrated HIZ. There was no significant predominance about age and gender for the presence of HIZ. HIZ occurred mainly at L4-5 (43.3%) and L5-S1 (30.2%) levels, infrequently at L3-4 (17%) and rarely at upper levels. The prevalence of disc degenerations with Pfirrmann grade 3, 4, and 5 were significantly higher in HIZ positive patients than in randomly selected 35 HIZ negative patients (64% vs. 46%, respectively). Conclusion; In this study we identified that the presence of HIZ was directly proportional to increased incidence of disc degeneration in remaining lumbar discs. The prevalence of significant degeneration was significantly higher in HIZ positive patient at lower three lumbar levels. J. Med. Invest. 64: 39-42, February, 2017.


A new concept of transforaminal ventral facetectomy including simultaneous decompression of foraminal and lateral recess stenosis: Technical considerations in a fresh cadaver model and a literature review.

Percutaneous endoscopic surgery for the lumbar spine, which was established in the last decade, requires only an 8-mm skin incision and causes minimal damage to the paravertebral muscles; thus, it is considered to be a minimally invasive technique for spinal surgery. It has been used to perform percutaneous endoscopic discectomy via two main approaches: the TF approach is a posterolateral one through the intervertebral foramen and can be done under local anesthesia; the IL approach is a more traditional one through the interlaminar space and is difficult to perform under local anesthesia. Recently, these techniques have been applied for lumbar spinal stenosis (LSS), the TF method for foraminal stenosis under local anesthesia, and the IL method for central and lateral recess stenosis under general anesthesia. In this study, using a fresh human cadaver model, we performed simultaneous decompression of the lateral recess and foraminal stenosis at L4-5 using the TF approach. Computed tomography confirmed enlargement of the lateral recess and intervertebral foramen. This technique, which can be performed under local anesthesia, should benefit elderly patients with LSS and poor general condition due to multiple comorbidities. Finally, we introduce the concept of percutaneous transforaminal ventral facetectomy using a spinal percutaneous endoscope. J. Med. Invest. 64: 1-6, February, 2017.


Diffusion tensor imaging and tractography of the sciatic nerve: assessment of fractional anisotropy and apparent diffusion coefficient values relative to the piriformis muscle, a preliminary study.

Piriformis muscle syndrome (PMS) is underdiagnosed. To evaluate the potential of diffusion tensor imaging and diffusion tensor tractography as innovative tools for the diagnosis of PMS by functional assessment of the sciatic nerve, the aims of this study are to assess the reproducibility and to evaluate the changes in the parameters at levels proximal and distal to the piriformis. Fractional anisotropy (FA) and the apparent diffusion coefficient (ADC) of the sciatic nerve at three levels were quantified twice each by two examiners using the fiber-tracking method. In the first part of the study, laterality and reproducibility were evaluated using intraclass correlation coefficients (ICC) in ten healthy volunteers. In the second part of the study, the healthy side and symptomatic side were assessed in ten consecutive patients with sciatica. There were three patients with no findings on lumbar magnetic resonance imaging (MRI). There was no laterality in either FA or ADC values in asymptomatic patients at any level. The mean intra-rater ICC was 0.90 and the mean inter-rater ICC was 0.87. FA was significantly lower and ADC significantly higher on the symptomatic side at each level in patients with sciatica. In the three sciatica patients with no findings on lumbar MRI, FA was significantly lower and ADC was significantly higher only at levels distal to the piriformis. These patients experienced full pain relief after ultrasound-guided injection of local anesthesia. Diffusion tensor imaging and diffusion tensor tractography might be innovative tools for the diagnosis of PMS.


Variations in arterial supply to the lower lumbar spine.

Various distributions of arteries around the lower spine were identified.

Each segmental artery was visible at the L1-4 spinal levels, running from the vertebra through the lamina in 91.0 % on the right side, in 90.7 % on the left side, while it was visible in 4.6 % on the right side, in 8.7 % on the left side at the L5 level. The extra-osseous arterial supply to the L5 lamina was basically provided by two vessels on each side. One was mostly derived from the L4 segmental artery (right: 92.6 %; left: 92.0 %) that was distributed around the superior articular process, the other was derived from the iliolumbar artery (right: 62.9 %; left: 55.7 %) that was distributed around the inferior articular process through the lamina. There were mainly four combination patterns of those arteries. These combinations, which had been considered as regular patterns in textbooks, were observed in approximately 50 % (right: 55.7 %; left: 48.6 %) of patients.


Proteomic Analysis of Human Tendon and Ligament: Solubilization and Analysis of Insoluble Extracellular Matrix in Connective Tissues.

Connective tissues such as tendon, ligament and cartilage are mostly composed of extracellular matrix (ECM). These tissues are insoluble, mainly due to the highly cross-linked ECM proteins such as collagens. Difficulties obtaining suitable samples for mass spectrometric analysis render the application of modern proteomic technologies difficult. Complete solubilization of them would not only elucidate protein composition of normal tissues but also reveal pathophysiology of pathological tissues. Here we report complete solubilization of human Achilles tendon and yellow ligament, which is achieved by chemical digestion combined with successive protease treatment including elastase. The digestion mixture was subjected to liquid chromatography-mass spectrometry. The low specificity of elastase was overcome by accurate mass analysis achieved using FT-ICR-MS. In addition to the detailed proteome of both tissues, we also quantitatively determine the major protein composition of samples, by measuring peak area of some characteristic peptides detected in tissue samples and in purified proteins. As a result, differences between human Achilles tendon and yellow ligament were elucidated at molecular level.


A Rare Case of Progressive Palsy of the Lower Leg Caused by a Huge Lumbar Posterior Endplate Lesion after Recurrent Disc Herniation.

A lesion of the lumbar posterior endplate is sometimes identified in the spinal canal of children and adolescents; it causes symptoms similar to those of a herniated disc. However, the pathology of the endplate lesion and the pathology of the herniated disc are different. We present a rare case of a 23-year-old woman who developed progressive palsy of the lower leg caused by huge lumbar posterior endplate lesion after recurrent disc herniation.


Vacuum Phenomenon of the Sacroiliac Joint: Correlation with Sacropelvic Morphology.

These data suggest that differences in sacropelvic morphology can influence the biomechanical environment and contribute to SJVP in men. Presence of SJVP did not affect JOA or RDQ scores.


Radiation Exposure to the Surgeon and Patient During a Fluoroscopic Procedure: How High is the Exposure Dose? A Cadaveric Study.

Seven fresh cadavers were irradiated for 1, 3, and 5 min with C-arm fluoroscopy. The X-ray source was positioned under the table, over the table, and laterally. Radiation exposure doses were measured at different simulated areas such as the center area, and the surgeon's hand or thyroid gland.


Lumbar Posterior Apophyseal Ring Fracture Combined with Spondylolysis in Pediatric Athletes: A Report of Three Cases.

In patients with severe low back and radicular pain in whom spondylolysis is suspected, it is important to perform not only magnetic resonance imaging and radiography but also computed tomography for identifying posterior apophyseal ring fractures.


Compression Myelopathy due to Proliferative Changes around C2 Pars Defects without Instability.

We report a case with compression myelopathy due to proliferative changes around the C2 pars defects without instability. A 69-year-old man presented with progressive clumsy hands and spastic gait. Plain radiographs showed bilateral spondylolysis (pars defects) at C2 and fusion between C2 and C3 spinous processes. Dynamic views revealed mobility through the pars defects, but there was no apparent instability. Computed tomography showed proliferative changes at the pars defects, which protruded into spinal canal. On magnetic resonance imaging, the spinal cord was compressed and intramedullary high signal change was found. A diagnosis of compression myelopathy due to proliferative changes around the C2 pars defects was made. We performed posterior decompression. Postoperatively, symptoms have been alleviated and images revealed sufficient decompression and no apparent instability. In patients with the cervical spondylolysis, myelopathy caused by instability or slippage have been periodically reported. The present case involving C2 spondylolysis is extremely rare.


Prevalence of Symptomatic Lumbar Spondylolysis in Pediatric Patients.

Lumbar spondylolysis, a stress fracture of the pars interarticularis, is prevalent in adolescent athletes. Recent advances in diagnostic tools and techniques enable early diagnosis before these fractures progress to complete fractures through the pars. However, because patients often consult family physicians for primary care of low back pain and these physicians may not have access to diagnostic modalities such as magnetic resonance imaging (MRI) and computed tomography, stress fractures can be missed. This study surveyed the prevalence of symptomatic spondylolysis in pediatric patients who consulted an orthopedic clinic for primary care and investigated whether such acute stress fractures may be overlooked without MRI. The prospective study investigated 264 patients who were younger than 19 years and had low back pain. Of the 153 patients (58.0%) with low back pain persisting for longer than 2 weeks, 136 who agreed to undergo MRI were included in the study. This group included 11 elementary school students, 71 junior high school students, and 54 high school students. The overall prevalence of lumbar spondylolysis was 39.7% (54 of 136) and was 9.3% in elementary school students (5 of 11, 45.5%), 59.3% in junior high school students (32 of 71, 45.1%), and 31.5% in high school students (17 of 54, 31.5%). All 54 patients with spondylolysis had a history of athletic activity. Primary care physicians should recognize that approximately 40% of pediatric patients presenting with low back pain persisting for longer than 2 weeks may have spondylolysis and should consider MRI in those with a history of athletic activity. Because the spine is immature in this age group, almost half of affected elementary school and junior high school students may have lumbar spondylolysis. [Orthopedics.].


Risk Assessment of Lumbar Segmental Artery Injury During Lateral Transpsoas Approach in the Patients with Lumbar Scoliosis.

This study demonstrated that female patients with lumbar scoliosis with an intersegmental Cobb angle > 14.5° would be at high risk for potential injury to the lumbar artery during a transpsoas approach for XLIF from the concave side.


Sacral fatigue fractures in children with sacral spina bifida occulta.

In this report, we present two cases of 9-year-old children with spina bifida occulta (SBO) of the sacrum, who were diagnosed with sacral fatigue fractures. In both patients, MRI showed a linear signal void and high signal in sacral ala on the short tau inversion recovery sequence. Sacral SBO at the same level of the sacral fracture was observed in each patient on computed tomography images. These lesions healed with rest. This is the first literature reporting cases with sacral stress fractures who had SBO at the same level of fracture.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially. http://creativecommons.org/licenses/by-nc-nd/4.0/.

Journal of Pediatric Orthopaedics. Part B


Clinical features of patients with pars defects identified in adulthood.

Lumbar spondylolysis is considered a stress fracture of the pars interarticularis that occurs during growth. However, it is sometimes insidious and identified in adults as pseudoarthrosis, the terminal-stage of spondylolysis. The purpose of this study was to identify the clinical features of patients with terminal-stage spondylolysis that first manifested during adulthood.

Approximately 90 % of patients with terminal-stage spondylolysis that was first diagnosed in adulthood involved the L5. Also, about 40 % had no history of athletic activity or experience of LBP during their growth period. In addition, only some patients with L5 spondylolysis had SBO, and all but one of these patients was male. This suggests that male patients with L5 spondylolysis may have some congenital predisposition.

European Journal of Orthopaedic Surgery & Traumatology


Risk Management for Avoidance of Major Vascular Injury due to Lateral Transpsoas Approach.

At the L3-4 level, the dorsal tangential line of the major vein located in zone A was found in 18% of subjects, in zone I in 74%, and in zone II in 8%. The line of the major artery was located in zone A in 92.6% of subjects and in zone I in 7.1%. At the L4-5 level, the line of the major vein was located in zone A in 5% of subjects, in zone I in 75%, in zone II in 20%, and in zone III in only 1 subject. The line of the major artery was identified in zone A in 87% of subjects, in zone I in 12%, and in zone II in 1%. Women had significant dorsal-migrated veins and arteries at both spinal levels (p < 0.01).


Postoperative discal cyst: An unusual complication after microendoscopic discectomy in teenagers.

Various complications after microendoscopic discectomy (MED) are well known, but postoperative discal cyst is a unique and relatively unknown complication. Here, we report on two teenage patients who presented with postoperative discal cyst after MED for herniated nucleus pulposus (HNP), which resolved after conservative treatment. The patients were diagnosed with HNP at L4-5 and L5-S1 based on MRI and then treated by MED. Postoperative discal cyst was diagnosed on MRI after recurrence of symptoms. Both patients were managed conservatively. T2-weighted MRI demonstrated hyperintense collections adjacent to the operated intervertebral disc level, which were communicating with the corresponding disc annulus. Because the clinical symptoms were relatively mild, the patients were managed conservatively; both made a complete clinical recovery with radiological evidence of improvement. Postoperative discal cyst is a relatively unknown complication after MED for HNP. Surgeons should be aware of this postoperative complication when operating on young individuals with HNP.


Characteristics of lumbar spondylolysis in elementary school age children.

Lumbar spondylolysis in elementary school age children was commonly a terminal-stage bone defect at L5, which was not necessarily related to history of athletic activity and was sometimes asymptomatic. It was often associated with SBO, indicating a possible congenital predisposition. These findings may provide further insight into the pathogenesis of lumbar spondylolysis.

Among the 30 patients, 27 (21 boys, 6 girls) had L5 spondylolysis (90.0 %). Only 2 patients had no history of athletic activity at the first consultation. All patients, except for 2 whose diagnosis was incidental, complained of low back pain. In the 27 patients with L5 spondylolysis, 17 (63.0 %) had terminal-stage fracture and 25 (92.6 %) had spina bifida occulta (SBO) involving the S1 lamina. Sixteen of the 27 (59.3 %) had SBO involving the affected lamina (L5) and S1 lamina. In contrast, the 3 patients with L3 or L4 spondylolysis had no evidence of SBO. With respect to skeletal age, 23 of the 27 L5 spondylolysis patients (85.2 %) were in the cartilaginous stage while the remaining 4 patients were in the apophyseal stage.


Delayed Diagnosis of Primary Bone and Soft Tissue Tumors Initially Treated as Degenerative Spinal Disorders.

Background Symptoms of primary bone and soft tissue tumors located in the trunk mimic those of degenerative spinal disorders such as low back pain or pain or numbness of the legs. Due to their rarity, especially in sarcoma located in the trunk, diagnosis is sometimes delayed. Methods A retrospective review was performed of the records of 383 patients with primary bone and soft tissue tumors who visit our out patient clinic from 2011 to 2013 at a single institution. Patients with delayed diagnosis of primary bone and soft tissue tumors initially treated as degenerative spinal disorders for more than 2 months were identified. Results Of the 383 patients, 5 (1.3%) were initially diagnosed as having degenerative spinal disorders. All 5 patients had bone or soft tissue tumors in the lumbar spine or pelvis. Three patients had a malignant tumor (osteosarcoma, chondrosarcoma, or small round cell sarcoma) at the progressive stage, and 1 died of lung metastasis. Two patients had a benign tumor (aneurysmal bone cyst or simple bone cyst). Conclusions Our findings suggest that when low back pain and leg pain are refractory to conservative treatment, further radiological examination should be conducted. J. Med. Invest. 63: 274-277, August, 2016.

The Journal of Medical Investigation : JMI