Evaluation of the efficacy and safety of conventional and interlaminar full-endoscopic decompressive laminectomy to treat lumbar spinal stenosis (ENDO-F trial): Protocol for a prospective, randomized, multicenter trial.

Lumbar spinal stenosis is a common spinal degenerative condition. Minimally invasive interlaminar full-endoscopic decompressive laminectomy provides greater patient satisfaction and faster recovery than open decompressive laminectomy. The aim of our randomized controlled trial will be to compare the safety and efficacy of interlaminar full-endoscopic laminectomy and open decompressive laminectomy. Our trial will include 120 participants (60 per group) who will undergo surgical treatment for lumbar spinal stenosis. The primary outcome will be the Oswestry Disability Index measured at 12 months postoperatively. Secondary patient-reported outcomes will include back and radicular leg pain measured via a visual analog scale; the Oswestry Disability Index; the Euro-QOL-5 Dimensions score measured at 2 weeks and at 3, 6, and 12 months postoperatively; and patient satisfaction. The functional measures will include time to return to daily activities postoperatively and walking distance/time. The surgical outcomes will include postoperative drainage, operation time, duration of hospital stay, postoperative creatine kinase (an indicator of muscle injury) level, and postoperative surgical scarring. Magnetic resonance and computed tomography images and simple radiographs will be obtained for all patients. The safety outcomes will include surgery-related complications and adverse effects. All evaluations will be performed by a single assessor at each participating hospital who will be blinded to group allocation. The evaluations will be conducted preoperatively and at 2 weeks and 3, 6, and 12 months postoperatively. The randomized, multicenter design of the trial, blinding, and justification of the sample size will reduce the risk of bias in our trial. The results of the trial will provide data regarding the use of interlaminar full-endoscopic laminectomy as an alternative to open decompressive laminectomy that results in similar surgical findings with less invasiveness. Trial registration: This trial is registered at cris.nih.go.kr. (KCT0006198; protocol version 1; 27 May 2021).

Comparative Analysis of ABM/P-15, Bone Morphogenic Protein and Demineralized Bone Matrix after Instrumented Lumbar Interbody Fusion.

OBJECTIVE: ABM/P-15 (anorganic bone matrix/15-amino acid peptide fragment) is a commercially available synthetically manufactured P-15 collagen peptide fragment, that is adsorbed on ABM. This study was done to investigate the efficacy of ABM/ P-15 in achieving fusion in the lumbar spine and comparing it with that of recombinant bone morphogenic protein-2 (rhBMP-2) and demineralized bone matrix (DBM). METHODS: A retrospective observational study of prospectively collected data of 140 patients who underwent lumbar spinal fusion surgeries in a single specialty spine hospital between 2016 and 2020, with a minimum 6-month follow-up was conducted. Based on the material used for the augmentation of the bone graft at the fusion site, the patients were divided into three categories namely ABM/P-15, rhBMP-2, and DBM group. RESULTS: ABM/P-15, rhBMP-2, and DBM were used in 46, 44, and 50 patients, respectively. Patient characteristics like age, gender, bone mineral density, smoking history, and presence of diabetes mellitus were comparable amongst the three groups. Average follow-up was 16.0±5.2, 17.9±9.8, and 26.2±14.9 months, respectively in ABM/P-15, rhBMP-2, and DBM groups. The fusion was achieved in 97.9%, 93.2%, and 98% patients while the average time-to-union was 4.05±2.01, 10±4.28, and 9.44±3.49 months (p<0.001), respectively for ABM/P-15, rhBMP-2, and DBM groups. The average pre-operative Visual analogue scale score was 6.93±2.42, 7.14±1.97, 7.01±2.14 (p=0.900) for ABM/P-15, rhBMP-2 and DBM groups, respectively, which reduced to 1.02±0.80, 1.21±0.96, and 0.54±0.70 (p=0.112), respectively at the last follow up. Pre-operative Oswestry disability index scores were 52.7±18.02, 55.4±16.8, and 53.56±19.6 (p=0.751) in ABM/P-15, rhBMP-2, and DBM groups, which post-operatively reduced to 33.77±15.52, 39.42±16.47, and 38.3±15.89 (p=0.412) and further to 15.74±8.3, 17.41±10.45, and 16.76±9.81 (p=0.603), respectively at the last follow-up. CONCLUSION: ABM/P-15 appears to achieve union significantly earlier than rhBMP-2 and DBM in lumbar spinal fusion cases while maintaining a comparable clinical and complication profile.

Comparative study of the efficacy and safety of minimally invasive interlaminar full-endoscopic discectomy versus conventional microscopic discectomy in single-level lumbar herniated intervertebral disc (ENDO-F Trial): a multicenter, prospective, randomized controlled trial protocol.

BACKGROUND: Advances in minimally invasive surgery have expanded the indications for interlaminar full-endoscopic discectomy. Although the clinical outcomes for this approach may be equivalent to those of conventional microscopic discectomy, the supporting evidence is still based on small, single-center, prospective, and retrospective studies. Therefore, a multicenter randomized controlled trial is warranted. METHODS: This will be a prospective, multicenter, randomized controlled trial comparing the efficacy and safety of interlaminar full-endoscopic discectomy to those of conventional microscopic discectomy. The trial will enroll 100 participants with a lumbar disc herniation, 50 in each group. The primary outcome will be the Oswestry Disability Index (ODI) score at 12 months post-surgery. Secondary outcomes will be back and leg pain (visual analog scale); the ODI; the EuroQol-5-dimension score; patient satisfaction; and walking distance/time and time to return to daily activities post-surgery. Surgical outcomes will include postoperative drainage, operative time, duration of hospital stay, postoperative creatine kinase level as an indicator of muscle injury, and postoperative scarring. Postoperative magnetic resonance imaging, computed tomography, and simple radiography will be performed to evaluate radiographic outcomes between the two surgical approaches. Surgery-related complications and adverse effects will be evaluated as safety outcomes. A single assessor at each participating hospital, blinded to group allocation, will assess the enrolled participants at baseline, at 2 weeks, and at 3, 6, and 12 months postoperatively. DISCUSSION: This trial is designed to determine whether interlaminar full-endoscopic discectomy is clinically comparable to microscopic discectomy to treat lumbar disc herniations. All efforts will be made to reduce bias, including adequate sample size, blinded analyses, and multicenter prospective registration. The outcomes will inform practice, providing the evidence needed for using interlaminar full-endoscopic over microscopic discectomy by confirming the potential of this technique to improve patient satisfaction and clinical outcomes. TRIAL REGISTRATION: Clinical Research Information Service; cris.nih.go.kr. (KCT0006277); protocol version (v1, June 8, 2021).

CT-guided percutaneous aspiration of Tarlov cyst: a case report of 2-year follow up.

Tarlov cysts are a rare pathology characterized by sac formations at the nerve root in the sacrum. Although many options have been proposed, there is still no consensus regarding the optimal treatment strategy. The authors report a case involving a 43-year woman with a sacral perineural cyst causing buttock pain and anus discomfort for 4 years. The patient successfully underwent computed tomography (CT)-guided aspiration. She currently has no symptoms, and 2-year follow-up magnetic resonance imaging revealed a decrease in cyst size. CT-guided aspiration is a safe and effective treatment option, and leads to improvement in cyst-related symptoms with minimal risk.

Interlaminar Percutaneous Endoscopic Lumbar Discectomy: Rotate and Retract Technique.

BACKGROUND: Interlaminar percutaneous endoscopic lumbar discectomy (PELD) is a minimally invasive technique to treat soft disc herniation. However, the currently used single working channel does not allow for safe nerve root retraction. This study aims to describe the rotate and retract technique for safe nerve root retraction during L5-S1 interlaminar PELD. METHODS: A total of 17 patients who underwent interlaminar PELD with the rotate and retract technique between November 2016 and August 2017 were retrospectively evaluated. Both pre- and postoperative visual analog scale (VAS) scores (back and leg) and Oswestry Disability Index (ODI) scores were used for clinical assessment. RESULTS: The mean preoperative VAS scores for back and leg pain were 3.84 ± 1.15 (range, 2-6) and 8.7 ± 0.2 (range, 8-10), respectively. The mean preoperative ODI score was 64.2 ± 13.2 (range, 48-90). The mean VAS scores for back and leg pain decreased to 1.24 ± 1.34 (range, 0-6) and 1.15 ± 0.65 (range, 0-4), respectively, at the last follow-up (P < 0.001). The mean ODI score also improved to 13.2 ± 5.1 (range, 9-29) at the last follow-up (P < 0.001). CONCLUSIONS: The rotate and retract technique for interlaminar PELD is an effective maneuver for the treatment of L5-S1 disc herniations in selected patients if performed by experienced surgeons.

A novel preoperative trajectory evaluation method for L5-S1 transforaminal percutaneous endoscopic lumbar discectomy.

BACKGROUND CONTEXT: L5-S1 transforaminal percutaneous endoscopic lumbar discectomy (PELD) is a demanding procedure because of structures such as iliac crest, L5 transverse process, hypertrophic L5-S1 facet joint, and sacral ala. There has been no definite preoperative evaluation method to evaluate the surgical validity of L5-S1 transforaminal PELD. PURPOSE: The authors report a new preoperative trajectory evaluation method for L5-S1 transforaminal PELD using magnetic resonance imaging (MRI) or computed tomography (CT) examinations. STUDY DESIGN/SETTING: This is a technical report study. PATIENT SAMPLE: Patients who were diagnosed L5-S1 soft disc herniation were included in the present study. OUTCOME MEASURES: Success rate of transforaminal PELD according to height of iliac crest was measured. METHODS: Twelve patients who were diagnosed L5-S1 disc herniation were preoperatively evaluated with this new method. A skin marker is attached to patient's back as a tentative skin entry point, which was determined by usual preoperative MRI or CT. A new tilted axial and coronal MRI or CT scan is performed according to axis of L5-S1 transforaminal working channel. The images show good relationship between working channel and iliac crest. RESULTS: Six patients underwent a transforaminal PELD, and the results were successful. The other six patients were considered to be "unsuitable" for transforaminal PELD because of the probable blockade by iliac crest. CONCLUSIONS: The tilted MRI or CT provides precise evaluation for L5-S1 transforaminal PELD trajectory and may achieve good outcome.

Transforaminal Percutaneous Endoscopic Lumbar Diskectomy for Downmigrated Disk Herniations: Lever-Up, Rotate, and Tilt Technique.

BACKGROUND AND STUDY AIMS: Although transforaminal percutaneous endoscopic lumbar diskectomy (PELD) offers certain advantages in the treatment of disk herniations, it used to be limited to nonmigrated or low-migrated herniations. With improvements in endoscopic spinal surgery, the range of indications for PELD has expanded. Various techniques including transforaminal and interlaminar approaches for migrated disk herniations are described in the literature. This study describes a transforaminal PELD approach to address downmigrated intracanal soft disk herniations effectively using the lever-up, rotate, and tilt technique. PATIENTS AND METHODS: We performed a retrospective review of 18 patients who had been operated on with the described technique between October 2012 and December 2015. We assessed clinical outcomes using the visual analog scale (VAS) for back and leg pain and the Oswestry Disability Index (ODI) preoperatively at their respective clinical visits and postoperatively at the patients' final follow-up examinations. RESULTS: The mean preoperative VAS scores for back and leg pain were 3.75 + 1.34 (range: 2-6) and 8.3 + 0.6 (range: 8-10), respectively. The mean preoperative ODI was 67.3 + 15.3 (range: 48-90). The mean VAS scores for back and leg pain improved to 1.38 + 1.58 (range: 0-6) and 1.19 + 0.75 (range: 0-3), respectively, at the last follow-up. The mean ODI also improved to 14.1 + 6.2 (range: 8-30) at the last follow-up. All differences between the preoperative and last follow-up scores were statistically significant (p < 0.05), Two surgeries failed because of a remnant disk fragment. CONCLUSIONS: The lever-up, rotate, and tilt technique for transforaminal PELD is an effective maneuver to treat downmigrated disk herniations in selected patients by experienced surgeons.

Three cases of L4-5 Baastrup's disease due to L5-S1 spondylolytic spondylolisthesis.

PURPOSE: Baastrup's disease is characterized by degeneration of spinous processes and interspinous soft tissue, which may cause spinal stenosis. Purpose of this article is to report the possible new cause of Baastrup's disease and result of surgical treatments. METHODS: Authors treated three cases of Baastrup's disease on L4-L5 with L5-S1 spondylolytic listhesis. Conservative treatment did not relieve the pain; therefore, surgical treatments were planned according to each specific disease condition. RESULTS: In one case, anterior lumbar interbody fusion of L5-S1 was performed, and after surgery, the size of epidural cyst on L4-L5 was decreased. L4-L5 bilateral laminectomy was performed to directly decompress posterior epidural cyst in a case with stable L5-S1 spondylolytic listhesis. In last case, facet joints and spinous process were removed by L5-S1 posterior lumbar interbody fusion (PLIF) surgery. After the surgery, patients' back and leg pain was improved and postoperative MRI revealed successful decompression of the spinal canal. Improvement in back and leg symptoms was noted at 12-month follow-up. CONCLUSIONS: Baastrup's disease at the L4-L5 level may have developed from the instability caused by L5-S1 spondylolytic spondylolisthesis. Viable treatment options include the fusion of L5-S1 or a laminectomy at the L4-L5 level.

Biportal Endoscopic Lumbar Decompression for Lumbar Disk Herniation and Spinal Canal Stenosis: A Technical Note.

Background and Study Aims Endoscopic lumbar diskectomy through the interlaminar window is gaining recognition. Most of the literature describes these endoscopic procedures using specialized uniportal multichannel endoscopes. However, a single portal limits the motion of the instruments and obscures visualization of the operating field. To overcome this limitation, we propose a new technique that utilizes two portals to access the spinal canal. The biportal endoscopic lumbar decompression (BELD) technique uses two portals to treat difficult lumbar disk herniations and also lumbar spinal stenoses. Patients and Methods Seventeen patients were treated with BELD for 11 lumbar disk herniations and 6 lumbar spinal stenoses. Preoperative back and leg visual analog scale (VAS-B and VAS-L, respectively) scores and the Oswestry Disability Index (ODI) were recorded and compared with corresponding values on final follow-up. Results There was an average follow-up of 14 months. For the disk herniation group, preoperative VAS-L (7.8750 ± 1.24) and ODI (51.73 ± 18.57) was significantly different from follow-up postoperative VAS-L (0.87 ± 0.64, p = 0.000) and ODI (9.37 ± 4.83, p = 0.001). For the stenosis group, preoperative VAS-B (6.17 ± 1.94), VAS-L(7.83 ± 1.47), and ODI (63.27 ± 7.67) were significantly different from follow-up postoperative values (2.5 ± 1.04, p = 0.022; 2.00 ± 1.67, p = 0.001; 24.00 ± 6.45, p = 0.000, respectively). One patient underwent revision microdiskectomy for incomplete decompression. Conclusions BELD can achieve a similar decompression effect as microdiskectomy and unilateral laminotomy for bilateral decompression with a smaller incision than tubular diskectomy.

Lamina Fenestration Technique for Treatment of Thoracic Ossified Ligamentum Flavum: 2-Year Follow-Up Result.

Background The incidence of thoracic ossification of ligamentum flavum (OLF) is increasing, and the available surgical techniques were invasive. Study Aims To evaluate the surgical outcome and prognostic factors in relation to clinicoradiologic variables with a novel minimally invasive lamina fenestration technique in patients with thoracic OLF. Patients and Methods Between July 2005 and November 2010, 27 levels with 50 lesions in 17 patients were treated with the lamina fenestration technique for the decompression of thoracic OLF. This technique creates a keyhole in the lamina, preserving lower lamina bone, facet joint, and ligamentum flavum. Patient outcome was analyzed using the Japanese Orthopaedic Association (JOA) score and progression of kyphosis on simple X-ray. Results All patients were successfully treated with the laminar fenestration technique. There was one dural tear but no neural complication or injury. Mean length of follow-up was 49 months. Mean JOA score improved from 4.88 to 7 (p = 0.000). Six patients had an excellent surgical outcome; 10 had a good surgical outcome according to JOA scoring. Conclusion The lamina fenestration technique for the treatment of thoracic OLF had a successful outcome with few complications. This technique can be a minimally invasive surgical option for the treatment of thoracic OLF.

Long-term Follow-up Results of Percutaneous Endoscopic Lumbar Discectomy.

BACKGROUND: Open lumbar microdiscectomy (OLM) has been considered the gold standard in the management of lumbar disc herniation (LDH) for its favorable outcomes in long-term follow-up. Nowadays, percutaneous endoscopic lumbar discectomy (PELD) is gaining recognition. However, greatest limitation of studies of PELD is the lack of long-term follow-up outcomes. OBJECTIVE: To investigate the long-term outcomes of PELD in terms of clinical and radiographic findings and revision surgery rate. STUDY DESIGN: Retrospective study. SETTING: Spine hospital. METHODS: Sixty-two patients who underwent PELD 10 years previously were contacted for follow-up. Clinical parameters such as the visual analog scale scores for the back and legs (VAS-B and VAS-L, respectively), the Oswestry disability index (ODI), and radiographic findings such as the disc-height ratio and change in the difference between flexion and extension were recorded and compared to the preoperative values. RESULTS: For 62 followed patients, 38 met our inclusion criteria (35 transforaminal, 3 interlaminar). Excluded were 6 patients (9.4%) who underwent revision OLM at same level and 17 patients (26.6%) who underwent lumbar spine surgery at other levels. The average follow-up period was 11.22 (± 0.83) years. For the remaining 38 patients who had no further surgery, the postoperative VAS-B (2.53 ± 1.98), VAS-L (1.82 ± 1.92), and ODI (12.69 ± 11.26) were significantly different from the pre-operative values (8.45 ± 1.52, 7.40 ± 3.04, and 55.33 ± 24.63, respectively; all P = 0.01). The average disc-height ratio was 81.54% of the original disc height. There was no evidence of instability after long-term postoperative follow-up. LIMITATION: Retrospective nature of data collection. CONCLUSION: PELD has favorable long-term outcomes.Key words: Long-term, PELD, endoscopic lumbar discectomy, revision rate, disc height, instability.

Arthroscopic repair of the posterior root of the medial meniscus using knotless suture anchor: A technical note.

There are numerous methods for repairing posterior root tears of the medial meniscus (PRTMM). Repair techniques using suture anchors through a high posteromedial portal have been reported. The present study found that using a knotless suture anchor instead of suture anchor seemed easier and faster because it avoided passing the sutures through the meniscus and tying a knot in a small space. This study describes a knotless suture anchor technique through a high posteromedial portal, and its clinical results.

Direct bursoscopic ossicle resection in young and active patients with unresolved Osgood-Schlatter disease.

PURPOSE: The aim of this study was to determine the outcomes of bursoscopic ossicle excision in young and active patients with unresolved Osgood-Schlatter disease. METHODS: This retrospective study included 18 male military recruits. A direct bursoscopic ossicle excision was performed using low anterolateral and low anteromedial portals. Outcomes were evaluated using the Lysholm knee score, pain score on a visual analog scale (VAS) (from 0 to 10), and Tegner activity scale score. In addition, patients were asked whether they could kneel or squat and whether they were able to return to their duty after surgery. Patient satisfaction was evaluated using the VAS and by asking whether patients thought that the prominence of the tibial tuberosity was reduced and whether they would recommend the same surgical treatment to others. Complications after surgery were also evaluated. RESULTS: The mean Lysholm knee score was 71 preoperatively and improved to 99 after surgery. The mean VAS pain score was 6.5 in the preoperative period and decreased to 0.9 after surgery. In addition, the mean Tegner activity scale score improved from 2.7 preoperatively to 6.2 at final follow-up. However, 4 patients were not able to return to their duty, and 4 patients still had difficulties with kneeling after surgery. A superficial infection occurred in 1 patient, and a recurrent ossicle formation was found in 1 patient. Of 18 patients, 17 were satisfied with their surgical outcomes, and the mean VAS score for patient satisfaction was 8.8. Furthermore, all but 1 patient would recommend the same surgical treatment to others. However, 6 patients did not believe that the prominence of the tibial tuberosity was reduced. CONCLUSIONS: Bursoscopic ossicle excision showed satisfactory outcomes in selective young and active patients with persistent symptoms. However, bursoscopic surgery showed limitation in reducing the prominence of the tibial tuberosity. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Twist technique for removal of spinal extradural arachnoid cyst: technical note.

STUDY DESIGN: We document a spinal extradual arachnoid cyst treated by twist technique. The cyst is tightly adherent to the neural tissue or the dura, and the communication stalk is little or short. OBJECTIVE: To demonstrate the effectiveness of twist technique of closure of the communication stalk for the removal of spinal extradural arachnoid cyst. The standard treatment for a spinal extradural arachnoid cyst is complete excision of the cyst, followed by obliteration of the communication stalk and repair of the dural defect. To our knowledge, twist technique of the communication stalk for removal of spinal extradural arachnoid cyst has not been reported. METHODS: A 44-year-old woman presented with a 10-year history of pain and dysesthesia, initially in the posterior neck region and extending gradually to the distal portion of the right upper extremity. Pain and dysesthesia were exaggerated when she was lying down and relieved when standing or walking. She was diagnosed with an extradural arachnid cyst ranging from spinal regions T1 to T3 using MRI. Computerized tomography myelography revealed a mass located posterior to the spinal cord. Pooling of contrast medium was observed in the lesion indicating communication with the subarachnoid space. Laminectomy of the T1-T3 region was performed, preserving the spinous processes and the facet joints. A short communication stalk was found at the proximal root sleeve of right T3. This stalk was closed using twist technique. RESULTS: The patient experienced marked reduction of pain and dysesthesia after surgery, and the headache and blurred vision completely disappeared. Five days after the operation, she was discharged home in good condition. Postoperative 1 year later, the patient had completely recovered and resumed her normal life. CONCLUSIONS: Twist technique can be seen safe and effective as another surgical option for spinal extradural arachnoid cysts containing a short stalk and dense fibrous adhesion with the dura mater.

Compatibility of the HINTEGRA prostheses with Korean ankles as evaluated on the basis of cadaveric measurements.

The purpose of this study was to obtain anatomical measurements of the distal tibia and talus of Korean ankles and to evaluate, based on those measurements, the compatibility of the HINTEGRA prostheses in the context of total ankle replacement (TAR). We measured the length, width, height, and angles of the distal tibia and talus of 51 cadavers and compared these measurements with the corresponding dimensions of the HINTEGRA prostheses. The male ankles were larger than the female ones as was expected, but their overall shapes did not differ, which fact validates use of the prostheses irrespective of patients' sex. The dimensions of the talus itself did not differ significantly from those previously reported for American whites and blacks and South African whites. This might suggest a possibility that the HINTEGRA prostheses, being used in these countries, would be compatible to Korean ankles, too. In fact, the length range of the talar components was generally compatible with those derived from cadaveric measurements of the trochlea. However, the widths of the tibial and talar components were not completely compatible to Korean ankles. Above all, the length of the large-sized tibial components was much longer than the largest ankles, which would confine the choice of prosthesis mainly to small-sized ones for arthroplasty in Korea. Even though these prostheses are currently used, some modifications are needed to extend their usability in Korea, such as shortening and width/length ratio adjustment of the tibial component, and of the talar component accordingly.

MRI versus CT for the diagnosis of lumbar spinal stenosis.

OBJECTIVE: The purpose of the study was to compare the effectiveness of CT and MRI in visualizing soft tissues in lumbar spinal stenosis (LSS), and to correlate the images with preoperative symptoms. MATERIALS AND METHODS: A total of 163 patients who had undergone unilateral laminotomy for bilateral decompression to treat LSS at L4-5 were retrospectively analyzed. The narrowed spinal canal area was measured on axial images with CT and MRI, and compared with the acquired dimensions from preoperative Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) scores. RESULTS: The mean compromised spinal canal areas were 75.08 mm(2) on MRI and 63.13 mm(2) on CT, which were significantly different. Mean VAS for back pain was 5.37, and 7.94 for leg pain. Mean ODI was 55.17%. There was no significant correlation noted between clinical parameters and narrowed spinal canal area. CONCLUSION: Spinal canal area was more narrowed on CT than on MRI in axial cuts. This finding can be explained by the superior ability of multidetector CT to discriminate cortical bone from soft tissue such as the ligamentum flavum. Our study highlights the value of CT examination in combination with MRI prior to LSS surgery.

Spinal meningeal melanocytoma in the S-1 nerve root sheath with paraspinal extension mimicking schwannoma.

BACKGROUND: Spinal melanocytomas are variants that can be extradural or intradural and are most often located in the intradural extramedullary compartment of the main thecal sac as in schwannomas. However, origin of this variant from the pure peripheral compartment of rootlets is exceedingly rare. CASE DESCRIPTION: The authors present a case of spinal melanocytoma with confusing pathologic and radiologic features. This patient presented clinically with severe radiating pain on the right lower extremity. Before surgery, clinical and radiologic findings were consistent with a schwannoma. However, on operation, a coal-black pigmented lesion mimicking old blood clot was found inside the right S-1 root sheath, attached to the dura. The mass was completely removed and consequently the patient's symptoms improved. CONCLUSIONS: The spinal melanocytoma should be included as a differential diagnosis before giving a presumptive diagnosis of schwannoma or hemorrhage for the patient with a space-occupying lesion at a peripheral rootlet. Intraoperative gross morphology and histopathologic findings facilitate differential diagnosis.

Modified transcorporeal anterior cervical microforaminotomy assisted by O-arm-based navigation: a technical case report.

This study was done to present our surgical experience of modified transcorporeal anterior cervical microforaminotomy (MTACM) assisted by the O-arm-based navigation system for the treatment of cervical disc herniation. We present eight patients with foraminal disc herniations at the C5-C6, C6-C7, and C7-T1 levels. All patients had unilateral radicular arm pain and motor weakness. The inclusion criteria for the patients were the presence of single-level unilateral foraminal cervical disc herniation manifesting persistent radiculopathy despite conservative treatment. Hard disc herniation, down-migrated disc herniation, concomitant moderate to severe bony spur and foraminal stenosis were excluded. We performed MTACM to expose the foraminal area of the cervical disc and removed the herniated disc fragments successfully using O-arm-based navigation. Postoperatively, the patients' symptoms improved and there was no instability during the follow-up period. MTACM assisted by O-arm-based navigation is an effective, safe, and precise minimally invasive procedure that tends to preserve non-degenerated structures as much as possible while providing a complete removal of ruptured disc fragments in the cervical spine.

Non-operative treatment of ACL rupture with mild instability.

PURPOSE: This study examined whether or not conservative treatment of an acutely injured anterior cruciate ligament (ACL) could be successful in a select group of patients. Routine ACL reconstruction surgery in all acute ACL-injured patients should be avoided. We hypothesize that acutely injured ACL with mild instability at the initial physical examination could be improved even if there is disruption of ACL fibers on magnetic resonance images (MRI). MATERIALS AND METHODS: Among 232 acute ACL-injured patients who visited our institution from March 1997 to April 2006, 48 were treated non-operatively. Patients diagnosed with an acute ACL injury by MRI with Lachman test < or =grade 1 were treated non-operatively. In this study, 30 male and 18 female patients with a mean age of 31.8 years were enrolled. The initial and follow-up Lachman test and pivot shift test were performed 3 weeks after the injury. The Lysholm knee scoring scale, International Knee Documentation Committee (IKDC) score and KT-2000 were obtained at the last follow-up. RESULTS: There were 12 complete (25%) and 36 incomplete ACL ruptures (75%). The patients were followed up clinically and with MRI for 21.5 and 11.3 months, respectively. The follow-up Lachman test improved to grade 0 in 41 patients (87%). Thirty-six patients (76%) showed no laxity in the follow-up pivot shift test. The last follow-up IKDC score was a mean value of 91.1 points. KT 2000 was performed in 40 patients with a mean side-to-side difference of 2.85 mm. Of 48 patients, 46 showed restored ACL continuity and 39 (84%) showed restored low signal intensity on MRI. CONCLUSION: A selective group of ACL tears with mild instability (Lachman < or =grade 1), though these seem to be complete tears on MRI, can show restoration of their continuity and signals on the MRI. Joint laxity on physical examination was improved at follow-up. These results suggest that a select group of patients with an acute ACL injury can successfully undergo non-operative treatment. In addition, unnecessary early ACL reconstruction surgery should be avoided.