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

STUDY DESIGN: Cross-sectional, observational. OBJECTIVE: To investigate the incidence of bidirectional lumbar facet tropism and its relationship with lumbar spine disease in adolescents. SUMMARY OF BACKGROUND DATA: There is limited information on facet joint asymmetry in the sagittal plane in adolescents. MATERIALS AND METHODS: 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. RESULTS: Facet tropism was observed in 8.7% of axial views and 7.5% of sagittal views. The incidence of axial facet tropism was significantly higher in male patients aged ≥15 years, especially at L4/5. Facet joint morphology in the axial plane was more coronal at L3/4 and L4/5 in male patients ≥15 years than in those <15 years. Facet joint morphology in the sagittal plane was unchanged at around 15 years of age in both sexes. Axial facet tropism was found at L4/5 in 55.6% of patients with herniated nucleus pulposus. There was a significant difference in sagittal facet orientation in patients with spondylolysis at L5. The facet angle was significant larger in patients with L5 spondylolysis at L3/4 and L4/5. CONCLUSION: 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.

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

BACKGROUND: Full-endoscopic lumbar surgery is used for decompression of lumbar spinal canal stenosis. Now, a cage can be inserted through Kambin's triangle for lumbar interbody fusion (LIF). We have been performing full-endoscopic trans-Kambin triangle LIF (KLIF) at our institution since 2018. In this article, we describe this technique and present our results. METHODS: We performed full-endoscopic one-level KLIF in 10 patients. The procedure is as follows. First, percutaneous pedicle screws are inserted. Listhesis is reduced if necessary. The endoscope is inserted in Kambin's triangle. Next, the superior articular process is partially removed, enlarging Kambin's triangle to allow safe insertion of the cage. A cannula is inserted into the disk to avoid damaging the exiting nerve. The disk material is shaved and curetted. Finally, the harvested bone is packed in a cage and inserted into the disk space. We analyze the complications, visual analog scores (VAS), and MacNab's criteria. RESULTS: One patient had an irritation in the exiting nerve at L4-L5. The VAS for back pain and leg pain decreased from 69 to 9 and from 60 to 9, respectively. The clinical outcome was considered excellent in eight and good in two patients. CONCLUSIONS: 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.

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.

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

STUDY DESIGN: A study using rat spondylolisthesis models. OBJECTIVE: The aim of this study was to elucidate the mechanism for correction of vertebral rounding deformity. SUMMARY OF BACKGROUND DATA: Vertebral rounding deformity is the strongest risk factor for high-grade slippage associated with spondylolisthesis in adolescents. We previously reported that inadequate endochondral ossification of the anterior upper corner of the vertebral growth plate in response to mechanical stress could be the pathological mechanism of vertebral rounding deformity. METHODS: We created a model of spondylolisthesis using 4-week-old rats. They were divided into a tail suspension group that underwent tail suspension to decrease mechanical stress starting at 2 weeks postoperatively and a ground control group with no intervention. Radiographs and microcomputed tomography scans were obtained once weekly for 6 weeks postoperatively. The lumbar spines were then harvested for histological analysis. Immunohistochemical studies detected types I, II, and X collagen in the growth plate cartilage. Bone histomorphometrical analysis was also performed. RESULTS: Radiological and histological evidence in the ground control group showed progress the rounding deformity with time as previously reported. Formation of normal cancellous bone was observed radiologically over time in the tail suspension group, indicating correction of rounding deformity. Histologically, the site showing radiological evidence of correction was derived from cartilage tissue. After starting tail suspension, the growth plate stained positive for type X collagen and the corrected site stained for types II and X collagen in a mosaic pattern. Chondrocytes expressing types I and II collagen and tartrate-resistant acid phosphatase-positive cells were also present at the corrected site. Histomorphometrically, more endochondral bone was detected at the corrected site than in the posterior aspect of the normal growth plate. CONCLUSION: 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.

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.

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.

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.

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.

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.

Return to play in professional baseball players following transforaminal endoscopic decompressive spine surgery under local anesthesia.

Transforaminal endoscopic discectomy has been established as the least minimally invasive spine surgical procedure because it avoids the surgical morbidity from surgical dissection and denervation of normal anatomy responsible for the functional stability of the spine. There have been few reports on endoscopic spine surgery for professional athletes who are dependent on the preservation of vital anatomy to maintain the highest level of function. This report is on five Japanese professional baseball players who underwent transforaminal endoscopic foraminoplasty-discectomy with pulsed radiofrequency thermal annuloplasty under the local anesthesia. There were no adverse surgical events nor complications. Three athletes suffered from discogenic back pain, one from symptomatic herniated nucleus pulposus (HNP), and another player from sciatica due to foraminal stenosis. Three players decided to undergo surgery at the beginning of the off-season. Therefore, they returned to professional play at the beginning of the following season. The remaining two players underwent surgery just before the beginning of the next season. They all returned to play sooner than with traditional open decompression. Two players returned to play about one month after the start of the season. All five players quickly returned to their sport within three months despite the rigors required of their sport to maintain high proficiency and were able to complete the season.

Intracanalicular Osteochondroma in the Lumbar Spine.

Osteochondroma is a common benign bone tumor that is relatively rare in the spine. Here, we report two cases of symptomatic solitary osteochondroma of the lumbar spine. The first case was a 61-year-old man who presented with a 2-year history of right leg numbness. Imaging findings showed that the cause of the radiculopathy was osteochondroma of the right inferior articular process at L4. The tumor was removed en bloc, and the numbness resolved. The second case was a 62-year-old man with osteochondroma of the right superior articular process at L5 that caused pain and numbness in the right leg. En bloc 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.

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.

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.

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.

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.

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.

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

PURPOSE OF THE REVIEW: Transforaminal full-endoscopic lumbar discectomy (TELD) under local anesthesia was first introduced in Japan in 2003. Initially referred to as percutaneous endoscopic discectomy, in 2018, a consensus was reached worldwide and the preferred term is now TELD. The procedure requires only an 8-mm skin incision and causes minimal damage to the paravertebral muscles. Thus, it is the least invasive disc surgery. In this review, we introduce two types of the TELD surgery. RECENT FINDINGS: 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.