Ambulatory uniportal versus biportal endoscopic unilateral laminotomy with bilateral decompression for lumbar spinal stenosis-cohort study using a prospective registry

BACKGROUND

Endoscopic spine surgery has been established as a practical, minimally invasive technique for decompression in patients with lumbar spinal stenosis. However, there remains a paucity of studies prospective cohort study comparing uniportal lumbar endoscopic unilateral laminotomy with bilateral decompression and unilateral biportal endoscopic unilateral laminotomy with bilateral decompression with open spinal decompression-both viable techniques with satisfactory clinical outcomes in the treatment of lumbar spinal stenosis.

OBJECTIVE/AIM

To compare the efficacy of UPE and BPE lumbar decompression surgery for patients with lumbar spinal stenosis.

METHODS

A prospective registry of patients who had undergone spinal decompression for lumbar stenosis via UPE or BPE under a single fellowship trained spine surgeon was studied. Baseline characteristics, initial clinical presentation, and operative details including complications were recorded for all included patients. Clinical outcomes, such as visual analogue scale and Oswestry Disability Index, were recorded at preoperative, immediate postoperative, 2-week, 3-, 6-, and 12-month follow-up periods.

RESULTS

A total of 62 patients underwent endoscopic decompression surgery for lumbar spinal stenosis (29 UPE, 33 BPE). No significant baseline differences were found between uniportal and biportal decompression, when comparing operative duration (130 vs. 140 min; p = 0.30), intraoperative blood loss (5.4 vs. 6mLs; p = 0.05), and length of hospital stay (23.6 vs. 20.3 h; p = 0.35). Two patients (7%) who underwent uniportal endoscopic decompression required conversion to open surgery due to inadequate decompression. Intraoperative complication rates were significantly higher in the UPE group (13.4% vs. 0%, p < 0.05). VAS score (leg & back) and ODI improved significantly (p < 0.001) in both endoscopic decompression groups across all follow-up time points, with no appreciable statistical differences between both groups.

CONCLUSION

UPE has the same efficacy as BPE in the treatment of lumbar spinal stenosis. While UPE surgery enjoys added aesthetic benefits of only one wound, BPE had potentially lower risks of intraoperative complication, inadequate decompression, and conversion to open surgery during early period of learning curve.

Posterior endoscopic decompression combined with anterior cervical discectomy and fusion versus posterior laminectomy and fusion for multilevel cervical spondylotic myelopathy: a retrospective case-control study

OBJECTIVE

To compare the clinical efficacy of surgical treatment for multilevel cervical spondylotic myelopathy (MCSM) between the hybrid procedure, posterior endoscopic decompression (PED) combined with anterior cervical discectomy fusion (ACDF), and posterior cervical laminectomy and fusion (PCLF).

METHODS

A retrospective analysis was performed on 38 patients who received surgical treatment for MCSM from January 2018 to December 2021, including 19 cases in hybrid procedure group (13 males and 6 females), followed up for 10 to 22 (12.8 ± 10.3) months, and 19 cases in PCLF group (15 males and 4 females), followed up for 10 to 21 (11.7 ± 8.9) months. Perioperative information, including operation time, intraoperative blood loss, length of hospitalization, and complications, were compared between two groups. Visual analogue scale (VAS) of pain, neck disability index (NDI) and Japanese Orthopaedic Association (JOA) score were recorded to evaluate clinical efficacy. Cervical lordosis was calculated by radiographic examination.

RESULTS

Intraoperative blood loss, length of hospital stay were less in hybrid group than PCLF group, while operation time is longer in hybrid group, with a statistically significant difference (p < 0.05). Increased lordosis was better in hybrid group. There was no significant difference in preoperative VAS, JOA and NDI at pre-operation and final follow-up between two groups. But at post-operation and final follow-up, VAS was less in hybrid group than PCLF group (p < 0.05). There were 2 cases of neurostimulation symptoms in hybrid group, 2 cases of C5 nerve root palsy, 2 cases of subcutaneous fat necrosis and 1 case of dural tear in PCLF group, and all patients relieved with symptomatic treatment.

CONCLUSION

The hybrid procedure of PED combined with ACDF showed satisfied clinical outcome, with less intraoperative blood loss, shorter length of hospitalization and lower post-operative neck pain than PCLF. It is an effective surgical treatment for MCSM.

[Research progress of different minimally invasive spinal decompression in lumbar spinal stenosis]

Objective

To review the application and progress of different minimally invasive spinal decompression in the treatment of lumbar spinal stenosis (LSS).

Methods

The domestic and foreign literature on the application of different minimally invasive spinal decompression in the treatment of LSS was extensively reviewed, and the advantages, disadvantages, and complications of different surgical methods were summarized.

Results

At present, minimally invasive spinal decompression mainly includes microscopic bilateral decompression, microendoscopic decompression, percutaneous endoscopic lumbar decompression, unilateral biportal endoscopy, and so on. Compared with traditional open surgery, different minimally invasive spinal decompression techniques can reduce the operation time, intraoperative blood loss, and postoperative pain of patients, thereby reducing hospital stay and saving treatment costs.

Conclusion

The indications of different minimally invasive spinal decompression are different, but there are certain advantages and disadvantages. When patients have clear surgical indications, individualized treatment plans should be formulated according to the symptoms and signs of patients, combined with imaging manifestations.

Comparison of the Degree of Expanded Spinal Canal Area between the Hinge-Side Area and the Open-Side Area in Cervical Open-Door Laminoplasty

Background

There have been reports on the significant canal cross-sectional area (CSA) expansion difference between pre- and post-operation, but no comparison of CSA expansion between the hinge-side area (Area H) and the open-side area (Area O) has been reported. This study aimed to measure the spinal CSA expansion between Area H and Area O retrospectively after open-door laminoplasty using new titanium spacers and evaluated this common decompression procedure's effectiveness.

Materials and Methods

This study included 27 patients diagnosed with cervical spondylotic radiculopathy or myelopathy, ossification of the posterior longitudinal ligament, and developmental canal stenosis from February 2021 to October 2022. The CSA difference between pre- and post-cervical laminoplasty (C4-C6 levels) was measured with cervical transverse computed tomography scan images. The CSA difference in Area H and Area O between pre- and post-laminoplasty was similarly calculated.

Results

The spinal canal areas of each segment after open-door laminoplasty were significantly enlarged (P < 0.05). Area O was also significantly enlarged compared to that of Area H (P < 0.05).

Conclusion

Area O was more enlarged than Area H, and both sides were statistically enlarged after open-door laminoplasty.

Spontaneous spinal epidural hematoma in a toddler presenting with torticollis: case report and literature review

INTRODUCTION

Spontaneous spinal epidural hematoma (SSEH) is a rare entity, especially in toddlers and infants. The nonspecificity of its presenting symptoms in children may be a source of delayed diagnosis.

CASE DESCRIPTION

We report the case of a 20-month-old young boy without medical history who presented with irreducible torticollis, worsened a few days later by severe tetraplegia and respiratory distress. Spinal magnetic resonance imaging (MRI) showed a posterior epidural hematoma, extending from C3 to T1 and compressing the spinal cord. An urgent decompressive surgery via an extensive laminectomy and evacuation of the clot was performed. The patient demonstrated a partial neurological recovery on follow-up.

CONCLUSION

SSEH is a rare and serious condition that may compromise the functional and vital prognosis of the patient, hence the importance of prompt diagnosis and urgent treatment.

Differences in spinal cord biomechanics after laminectomy, laminoplasty, and laminectomy with fusion for degenerative cervical myelopathy

OBJECTIVE

Spinal cord stress/strain during neck motion contributes to spinal cord dysfunction in degenerative cervical myelopathy (DCM), yet the effect of surgery on spinal cord biomechanics is unknown. It is expected that motion-preserving and fusion surgeries for DCM will have distinct effects on spinal cord biomechanics. The aim of this study was to compare changes in spinal cord biomechanics after laminectomy with fusion, laminectomy, and laminoplasty using a patient-specific finite element model (FEM) for DCM.

METHODS

A patient-specific FEM of the cervical spine and spinal cord was created using MRI from a subject with mild DCM. Multilevel laminectomy with fusion, laminectomy, and laminoplasty were simulated for DCM using the patient-specific FEM. Spinal cord von Mises stress and maximum principal strain during neck flexion-extension, lateral bending, and axial rotation were recorded. Segmental range of motion, intradiscal pressure, and capsular ligament strain were also measured. FEM outputs were calculated as a change with respect to the preoperative values and compared between the three models.

RESULTS

Across the surgical levels, spinal cord stress increased after laminectomy for neck flexion (+50%), neck extension (+37.8%), and axial rotation (+23%). Similarly, spinal cord strain increased in neck extension (+118.4%) and axial rotation (+75.1%) after laminectomy. Laminoplasty was associated with greater spinal cord stress in neck flexion (+57.4%) and increased strain in lateral bending (+56.7%) and axial rotation (+20.9%). Compared with laminectomy and laminoplasty, spinal cord biomechanics for laminectomy with fusion revealed significantly reduced median extension stress (13.7 kPa vs 9.7 kPa, p = 0.03), lateral bending strain (0.01 vs 0.007, p = 0.007), axial rotation stress (3.7 kPa vs 2.1 kPa, p = 0.04), and axial rotation strain (0.017 vs 0.009, p = 0.04).

CONCLUSIONS

Spinal cord strain decreased in neck flexion in all three models, yet spinal cord stress increased with neck flexion for laminectomy and laminoplasty. Changes in spinal cord biomechanics for laminoplasty parallel those for laminectomy with fusion except during neck flexion, lateral bending, and axial rotation. Compared with motion-preserving approaches such as laminectomy and laminoplasty, laminectomy with fusion was associated with the lowest spinal cord stress and strain in flexion-extension, lateral bending, and axial rotation of the neck.

Insidious onset of spontaneous spinal epidural hematoma in immune thrombocytopenic purpura: a case-based review

INTRODUCTION

Spontaneous spinal epidural hematoma (SSEH) can result from various etiologies with a variable degree of neurological deficits. Here, we describe a rare case of SEH secondary to immune thrombocytopenic purpura (ITP) in a child and review the literature of SSEH caused by ITP.

CASE REPORT

A 9-year-old female who presented with rapid neurological decline, including bowel and bladder incontinence and paraparesis. A SSEH was observed extending from C2 to T6, causing a mass effect on the spinal cord. Her platelet count was only 7000/µL. Multidisciplinary care was established with neurosurgery, pediatric hematology, and pediatric surgery. The patient was managed emergently with splenectomy and surgical evacuation, with multilevel laminectomy and laminoplasty for evacuation of the hematoma. After a short course of rehabilitation, the patient regained all neurological function.

CONCLUSION

We report the first case of cervicothoracic SSEH secondary to ITP in a child managed with emergent splenectomy and surgical evacuation with multilevel lamoplasty. We also described the methods of timely diagnosis, urgent management, and overall prognosis of patients with this condition.

Quantitatively biomechanical response analysis of posterior musculature reconstruction in cervical single-door laminoplasty

BACKGROUND AND OBJECTIVE

The current trend of laminoplasty is developing toward the goal of muscle preservation and minimum tissue damage. Given this, muscle-preserving techniques in cervical single-door laminoplasty have been modified with protecting the spinous processes at the sites of C2 and/or C7 muscle attachment and reconstruct the posterior musculature in recent years. To date, no study has reported the effect of preserving the posterior musculature during the reconstruction. The purpose of this study is to quantitatively evaluate the biomechanical effect of multiple modified single-door laminoplasty procedures for restoring stability and reducing response level on the cervical spine.

METHODS

Different cervical laminoplasty models were established for evaluating kinematics and response simulations based on a detailed finite element (FE) head-neck active model (HNAM), including ① C3 - C7 laminoplasty (LP_C37), ② C3 - C6 laminoplasty with C7 spinous process preservation (LP_C36), ③ C3 laminectomy hybrid decompression with C4 - C6 laminoplasty (LT_C3 + LP_C46) and ④ C3 - C7 laminoplasty with unilateral musculature preservation (LP_C37 + UMP). The laminoplasty model was validated by the global range of motion (ROM) and percentage changes relative to the intact state. The C2 - T1 ROM, axial muscle tensile force, and stress/strain levels of functional spinal units were compared among the different laminoplasty groups. The obtained effects were further analysed by comparison with a review of clinical data on cervical laminoplasty scenarios.

RESULTS

Analysis of the locations of concentration of muscle load showed that the C2 muscle attachment sustained more tensile loading than the C7 muscle attachment, primarily in flexion-extension (FE) and in lateral bending (LB) and axial rotation (AR), respectively. Simulated results further quantified that LP_C36 primarily produced 10% decreases in LB and AR modes relative to LP_C37. Compared with LP_C36, LT_C3 + LP_C46 resulted in approximately 30% decreases in FE motion; LP C37 + UMP also showed a similar trend. Additionally, when compared to LP_C37, LT_C3 + LP_C46 and LP C37 + UMP reduced the peak stress level at the intervertebral disc by at most 2-fold as well as the peak strain level of the facet joint capsule by 2-3-fold. All these findings were well correlated with the result of clinical studies comparing modified laminoplasty and classic laminoplasty.

CONCLUSIONS

Modified muscle-preserving laminoplasty is superior to classic laminoplasty due to the biomechanical effect of the posterior musculature reconstruction, with a retained postoperative ROM and loading response levels of the functional spinal units. More motion-sparing is beneficial for increasing cervical stability, which probably accelerates the recovery of postoperative neck movement and reduces the risk of the complication for eventual kyphosis and axial pain. Surgeons are encouraged to make every effort to preserve the attachment of the C2 whenever feasible in laminoplasty.

Comparison of clinical outcomes of modified laminoplasty with preservation of muscle group inserted into C2 and C7 spinous processes versus conventional C3-C7 laminoplasty: a prospective, randomized, controlled, noninferiority trial

BACKGROUND

The efficacy and noninferior of performing modified double-door laminoplasty (MDDL) (C4-C6 laminoplasty plus C3 laminectomy, alongside a dome-like resection of the inferior part of the C2 lamina and the superior part of the C7 lamina) in patients with multilevel cervical spondylotic myelopathy (MCSM) is equivocal. A randomized, controlled trial is warranted.

OBJECTIVE

The objective was to evaluate the clinical efficacy and noninferior of MDDL compared with traditional C3-C7 double-door laminoplasty.

STUDY DESIGN

A single-blind, randomized, controlled trial.

METHODS

A single-blind, randomized, controlled trial was conducted in which patients who with MCSM with greater than or equal to 3 levels of spinal cord compression from the C3 to the C7 vertebral levels were enrolled and assigned to undergo either MDDL group or conventional double-door laminoplasty (CDDL) group in a 1:1 ratio. The primary outcome was the change in the Japanese Orthopedic Association score from baseline to 2-year follow-up. The secondary outcomes included changes in the Neck Disability Index (NDI) score, the Visual Analog Scale (VAS) for neck pain, and imaging parameters. Operative complications were also collected and reported. The outcome measures were compared between the groups at 3 months, 1 year, or 2 years after surgery.

RESULTS

A total of 96 patients (mean age 67 years, 39.8% women) underwent randomization. Of these patients, 93 completed 3-month follow-up, 79 completed 1-year follow-up, and 66 completed 2-year follow-up. The changes in the Japanese Orthopedic Association score did not differ significantly between the study groups at the three time points after surgery. With respect to amelioration of neck pain and disability related to neck pain, patients in the MDDL group had a significantly greater decrease in the VAS and NDI component summary score than did those in the CDDL group at 1-year (VAS: -2.5 vs. -3.2, difference -0.7, 95% CI -1.1 to -0.2, P =0.0035; NDI: -13.6 vs. -19.3, difference -5.7, 95% CI -10.3 to -1.1, P =0.0159) and 2-years (VAS: -2.1 vs. -2.9, difference -0.8, 95% CI -1.4 to -0.2, P =0.0109; NDI: -9.3 vs. -16.0, difference -6.7, 95% CI -11.9 to -1.5, P =0.0127). The changes in the range of motion (ROM), the C2-C7 Cobb angle, and the cervical sagittal vertical axis in the MDDL group were significantly less than those in the CDDL group (ROM: -9.2±6.4 vs. -5.0±6.0, P =0.0079; C2-C7 Cobb angle: -7.9±7.8 vs. -4.1±6.2, P =0.0345; cervical sagittal vertical axis: 0.6±0.9 vs. 0.2±0.6, P =0.0233). The MDDL group had less blood loss (428.1 vs. 349.1, P =0.0175) and a lower rate of axial symptoms (27.3 vs. 6.1%, P =0.0475) than the CDDL group.

CONCLUSIONS

Among patients with MCSM, the MDDL produced similar cervical cord decompression compared with the conventional C3-C7 double-door laminoplasty. The modified laminoplasty was associated with meaningful improvement in amelioration of neck discomfort, maintaining a better cervical ROM and sagittal alignment, decreasing blood loss, and reducing the incidence of axial symptoms.

Percutaneous Biportal Endoscopic Fenestration for Symptomatic Foraminal Tarlov Cyst

Perineural (Tarlov) cysts are a common benign pathology in the lumbosacral area but are rarely symptomatic, even when compressing the spinal root. Despite the rarity of Tarlov cyst formation in the foramen of the spine, this type is more symptomatic than those in other sites due to the narrow space. We introduce a biportal endoscopic fenestration for symptomatic foraminal Tarlov cysts. We present the case of a 40-year-old woman experiencing radiating pain in her right lower leg for 4 years. On seeking treatment, her great toe and ankle plantar flexion power had decreased. Magnetic resonance imaging revealed a cystic mass located in the L5-S1 intervertebral foramen that compressed the lumbar nerve root. Partial laminotomy was performed using a percutaneous biportal endoscopic system with a far lateral approach. An oval cystic mass of 2.6×1.1 cm was identified on high-definition images. Partial bone and foraminal ligament removal and cystic membrane fenestration were performed for nerve decompression. After decompression, the patient's motor weakness and radiating pain improved. Due to high-definition images and the minimally invasive laminotomy procedures associated with percutaneous biportal endoscopic fenestration, a foraminal Tarlov cyst was fenestrated safely, and weakness arising from radiculopathy was resolved in the current case. [Orthopedics. 2023;46(2):e125-e128.].

Surgical Decompression of Traumatic Cervical Spinal Cord Injury: A Pilot Study Comparing Real-Time Intraoperative Ultrasound After Laminectomy With Postoperative MRI and CT Myelography

BACKGROUND

Decompression of the injured spinal cord confers neuroprotection. Compared with timing of surgery, verification of surgical decompression is understudied.

OBJECTIVE

To compare the judgment of cervical spinal cord decompression using real-time intraoperative ultrasound (IOUS) following laminectomy with postoperative MRI and CT myelography.

METHODS

Fifty-one patients were retrospectively reviewed. Completeness of decompression was evaluated by real-time IOUS and compared with postoperative MRI (47 cases) and CT myelography (4 cases).

RESULTS

Five cases (9.8%) underwent additional laminectomy after initial IOUS evaluation to yield a final judgment of adequate decompression using IOUS in all 51 cases (100%). Postoperative MRI/CT myelography showed adequate decompression in 43 cases (84.31%). Six cases had insufficient bony decompression, of which 3 (50%) had cerebrospinal fluid effacement at >1 level. Two cases had severe circumferential intradural swelling despite adequate bony decompression. Between groups with and without adequate decompression on postoperative MRI/CT myelography, there were significant differences for American Spinal Injury Association motor score, American Spinal Injury Association Impairment Scale grade, AO Spine injury morphology, and intramedullary lesion length (IMLL). Multivariate analysis using stepwise variable selection and logistic regression showed that preoperative IMLL was the most significant predictor of inadequate decompression on postoperative imaging (P = .024).

CONCLUSION

Patients with severe clinical injury and large IMLL were more likely to have inadequate decompression on postoperative MRI/CT myelography. IOUS can serve as a supplement to postoperative MRI/CT myelography for the assessment of spinal cord decompression. However, further investigation, additional surgeon experience, and anticipation of prolonged swelling after surgery are required.

Usefulness of Source Images of Magnetic Resonance Myelograms and Partial Laminectomy for Interlaminar Endoscopic Lumbar Discectomy at L5-S1: A Technical Note and Preliminary Clinical Results

ABSTRACT

The primary objective of this study was to assess the clinical and radiologic outcomes and introduce the technical notes from 10 patients who underwent interlaminar endoscopic lumbar discectomy (IELD) at L5-S1 using the source images of magnetic resonance (MR) myelograms and performing partial laminectomy. A biportal endoscopic system was used to perform partial laminectomy, followed by fragmentectomy and subtotal discectomy using a uniportal endoscopic system. The source images of MR myelograms were used to identify the anatomical relationship between the herniated disc material, L5 and S1 nerve roots, the thecal sac, and L5 lamina. Preoperative leg and back visual analog scale scores were greatly improved immediately and after 3 months and 6 months postoperatively. Fragmentectomy and subtotal discectomy became easier after performing a partial laminectomy in all IELD cases at L5-S1. The source images of MR myelograms and partial laminectomy is useful for IELD at L5-S1.

LEVEL OF EVIDENCE

Level IV.

Learning curve for microscopic unilateral laminectomy for bilateral decompression surgery using the cumulative summation test for learning curve

A retrospective observational study The purpose of this study was to characterize the learning curve for a single level unilateral laminectomy and bilateral decompression in lumbar spinal stenosis using a learning curve cumulative summation test. Unilateral laminectomy and bilateral decompression for lumbar spinal stenosis proposes a potential benefit with minimizing surgery-related instability compared to traditional bilateral laminectomy, by preserving posterior stabilizing structures and contralateral facet joint and neural arch. Due to a narrow surgical corridor, it is considered to exhibit a steep learning curve as other types of minimally invasive procedures. However, there are few reports available regarding learning curve of unilateral laminectomy and bilateral decompression. The learning curve of a single surgeon performing single level unilateral laminectomy and bilateral decompression was assessed using learning curve cumulative summation test analysis. The surgeon had minimal experience in open decompressive laminectomy but no previous experience in unilateral laminectomy and bilateral decompression. Procedure success was defined as an operation time less than 75 minutes. Surgery related complications were recorded. Total 194 consecutive patients, who underwent primary single level unilateral laminectomy and bilateral decompression by a single spine surgeon, were included. The mean operative time for unilateral laminectomy and bilateral decompression was 64.6 ± 23.6 minutes. The mean operative time in the early learning period (≤29th case) was 80.6 ± 20.9 minutes, and that in the late learning period (after 29th case) was 61.8 ± 22.7 minutes, respectively. The overall complication rate was 13.9%. Majority of complications occurred in the early learning period. The learning curve cumulative summation test signaled competency for unilateral laminectomy and bilateral decompression at the 29th operation, indicating that the surgeon reached the competent level. In addition, based on the cumulative summation test, the surgeon seemed to maintain his competency for the procedure. This study showed that surgical experience reduced the operation time and surgery related complications. For inexperienced surgeon to achieve an acceptable outcome in unilateral laminectomy and bilateral decompression, minimum 30 cases of unilateral laminectomy and bilateral decompression are required to reach competent level of surgery.

Laminectomy with Rib Shears: A Technical Note

INTRODUCTION

Laminectomy/laminoplasty either free or vascularized pedicle flap is currently performed with a variety of expensive instruments. Use of Tudor Edwards rib shears to perform above procedure is described.

MATERIALS AND METHODS

Tudor Edwards rib shear was used to cut lamina in 18 cases for a variety of spinal lesions. Depending upon the size of lesion, laminectomy/laminoplasty was required for 2 to 8 levels. Vascularized pedicle laminoplasty or free flap laminoplasty was done with Tudor Edwards rib shears. Ligamentum flavum and interspinous and supraspinous ligaments were preserved in cases of vascularized pedicled laminoplasty, which was carried out in 12 cases. Free flap laminoplasty was carried out in 6 cases.

RESULTS

In all our cases, laminectomy was successfully achieved with rib shears without any injury to the dura or its underlying structures. It was possible to perform vascularized pedicle laminoplasty or free flap laminoplasty in all cases. Laminectomy was easier to perform in the cervical region and dorsal region, while it was difficult in the lumbar region due to the wider, thick lamina and its angulation, especially in adults.

CONCLUSION

Laminectomy/laminoplasty with Tudor Edwards rib shears is quick, safe, and easy. Beveled cut edges with minimal bony loss prevents sinking of laminoplasty, thereby facilitates lamina fixation. This is an alternative method of performing laminectomy/laminoplasty, especially for those not having accessibility to expensive equipment.

Biomechanical analysis of laminectomy, laminoplasty, posterior decompression with instrumented fusion, and anterior decompression with fusion for the kyphotic cervical spine

PURPOSE

Anterior and posterior decompressions for cervical myelopathy and radiculopathy may lead to clinical improvements. However, patients with kyphotic cervical alignment have sometimes shown poor clinical outcomes with posterior decompression. There is a lack on report of mechanical analysis of the decompression procedures for kyphotic cervical alignment.

METHODS

This study employed a three-dimensional finite element (FE) model of the cervical spine (C2-C7) with the pre-operative kyphotic alignment (Pre-OK) model and compared the biomechanical parameters (range of motion (ROM), annular stresses, nucleus stresses, and facet contact forces) for four decompression procedures at two levels (C3-C5); laminectomy (LN), laminoplasty (LP), posterior decompression with fusion (PDF), and anterior decompression with fusion (ADF). Pure moment with compressive follower load was applied to these models.

RESULTS

PDF and ADF models' global ROM were 40% at C2-C7 less than the Pre-OK, LN, and LP models. The annular and nucleus stresses decreased more than 10% at the surgery levels for ADF, and PDF, compared to the Pre-OK, LN, and LP models. However, the annular stresses at the adjacent cranial level (C2-C3) of ADF were 20% higher. The nucleus stresses of the caudal adjacent level (C5-C6) of PDF were 20% higher, compared to other models. The PDF and ADF models showed a less than 70% decrease in the facet forces at the surgery levels, compared to the Pre-OK, LN, and LP models.

CONCLUSION

The study concluded that posterior decompression, such as LN or LP, increases ROM, disc stress, and facet force and thus can lead to instability. Although there is the risk of adjacent segment disease (ASD), PDF and ADF can stabilize the cervical spine even for kyphotic alignments.

A Pediatric Case of Cauda Equina Dermoid Cyst Resected by Minimally Invasive Unilateral Hemilaminectomy

A 3-year-old boy had difficulty sitting up and walking for several months. Magnetic resonance imaging (MRI) revealed an intradural tumor at the L3-4 level. The tumor was successfully resected by unilateral hemilaminectomy and diagnosed as dermoid cyst. The patient had an uneventful postoperative course without pain, and MRI found no recurrence after surgery. A small bone defect remained that might be favorably reconstructed with autologous and artificial bone. Hemilaminectomy allowed us to resect the cauda equina dermoid cyst with minimal invasiveness. Pediatric patients require follow-up as they are more likely to experience spinal deformity or instability after surgery.

Laminectomy at T4 and T5 for Resection of Symptomatic Cavernous Malformation

Although rare, intramedullary spinal cavernous malformations have a 1.4%-6.8% annual hemorrhage risk and can cause significant morbidity.¹ Prior hemorrhage and size >1 cm are risk factors for future hemorrhage that, in addition to notable or progressive symptoms, may justify early surgical intervention.^1,2 In this video, we present key steps in surgical management of a large, symptomatic thoracic cavernous malformation. A 56-year-old woman presented with worsening lower extremity weakness, imbalance, and difficulty ambulating. Strength was 3/5 in her right lower extremity and 4/5 in her left lower extremity. She had an incomplete T4 sensory level and hyperreflexia. Magnetic resonance imaging demonstrated a heterogeneous "popcorn"-appearing expansile intradural intramedullary 2.2- × 1.2-cm lesion at T4-5, consistent with a cavernous malformation. Angiography was deferred given the characteristic magnetic resonance imaging appearance. Given her progressive symptoms (including weakness), lesion size, and good health, resection was recommended. Using neurological monitoring, a T4-5 laminectomy, midline myelotomy, and piecemeal microsurgical resection of the lesion was performed, clearly identifying the cavernoma-spinal cord interface and avoiding spinal cord retraction. Histopathology confirmed a cavernoma. Postoperatively, the patient had improved left lower extremity strength and stable right lower extremity strength but worsened dorsiflexion (1/5), which improved with rehabilitation. At 1-year follow-up, she had full strength in her left lower extremity and 4/5 in her right lower extremity, with mild paresthesias below T10. Consistent with prior series demonstrating low complication rates and good long-term neurological outcomes,² microsurgical resection of selected symptomatic intramedullary spinal cavernous malformations can halt neurological decline and potentially improve neurological function.

Comparison of 3 Different Minimally Invasive Surgical Techniques for Lumbar Spinal Stenosis: A Randomized Clinical Trial

IMPORTANCE

Operations for lumbar spinal stenosis is the most often performed surgical procedure in the adult lumbar spine. This study reports the clinical outcome of the 3 most commonly used minimally invasive posterior decompression techniques.

OBJECTIVE

To compare the effectiveness of 3 minimally invasive posterior decompression techniques for lumbar spinal stenosis.

DESIGN, SETTING, AND PARTICIPANTS

This randomized clinical trial used a parallel group design and included patients with symptomatic and radiologically verified lumbar spinal stenosis without degenerative spondylolisthesis. Patients were enrolled between February 2014 and October 2018 at the orthopedic and neurosurgical departments of 16 Norwegian public hospitals. Statistical analysis was performed in the period from May to June 2021.

INTERVENTIONS

Patients were randomized to undergo 1 of the 3 minimally invasive posterior decompression techniques: unilateral laminotomy with crossover, bilateral laminotomy, and spinous process osteotomy.

MAIN OUTCOMES AND MEASURES

Primary outcome was change in disability measured with Oswestry Disability Index (ODI; range 0-100), presented as mean change from baseline to 2-year follow-up and proportions of patients classified as success (>30% reduction in ODI). Secondary outcomes were mean change in quality of life, disease-specific symptom severity measured with Zurich Claudication Questionnaire (ZCQ), back pain and leg pain on a 10-point numeric rating score (NRS), patient perceived benefit of the surgical procedure, duration of the surgical procedure, blood loss, perioperative complications, number of reoperations, and length of hospital stay.

RESULTS

In total, 437 patients were included with a median (IQR) age of 68 (62-73) years and 230 men (53%). Of the included patients, 146 were randomized to unilateral laminotomy with crossover, 142 to bilateral laminotomy, and 149 to spinous process osteotomy. The unilateral laminotomy with crossover group had a mean change of -17.9 ODI points (95% CI, -20.8 to -14.9), the bilateral laminotomy group had a mean change of -19.7 ODI points (95% CI, -22.7 to -16.8), and the spinous process osteotomy group had a mean change of -19.9 ODI points (95% CI, -22.8 to -17.0). There were no significant differences in primary or secondary outcomes among the 3 surgical procedures, except a longer duration of the surgical procedure in the bilateral laminotomy group.

CONCLUSIONS AND RELEVANCE

No differences in clinical outcomes or complication rates were found among the 3 minimally invasive posterior decompression techniques used to treat patients with lumbar spinal stenosis.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02007083.

[A case-control study:the clinical efficacy of total laminectomy with lateral mass screw fixation and single open-door laminoplasty for cervical spinal cord injury without fracture and dislocation]

OBJECTIVE

To compare the clinical effects of total laminectomy with lateral mass screw fixation and single open-door laminoplasty in the treatment of cervical spinal cord injury without fracture and dislocation.

METHODS

The clinical data of 75 patients with cervical spinal cord injury without fracture and dislocation treated from December 2014 to April 2020 were retrospectively analyzed, including 65 males and 10 females, aged from 33 to 83 years old with an average of (60.1±11.4) years. According to surgical method, the patients were divided into observation group (36 cases) and control group (39 cases). The observation group was treated with C₃-C₆ single open-door laminoplasty. In the control group, the C₃-C₆ whole lamina was opened by "uncovering", and the lateral mass screw was fixed and fused. The general conditions including operation time, intraoperative blood loss, hospital stay and complications such as axial pain, cerebrospinal fluid leakage, postoperative C₅ nerve palsy were recorded. Visual analogue scale(VAS), Nurick pain scale, Japanese Orthopaedic Association(JOA) scores and American Spinal Injury Association(AISA) injury scale were used to evaluate the improvement of clinical symptoms and related functional recovery 12 months after operation.

RESULTS

There were no statistically significant differences in operation time, intraoperative blood loss and hospital stay between two groups(P>0.05). There were statistically significant differences in JOA, VAS, ASIA and Nurick scores of the all patients between 12 months after surgery and before surgery (P<0.05), and there was no significant difference between groups. There was significant difference in the incidence of C5 nerve root palsy and axial pain between two groups(P<0.05), but there was no significant difference in the complications of cerebrospinal fluid leakage between two groups (P>0.05).

CONCLUSION

Total laminectomy with lateral mass screw fixation and single open-door laminoplasty in treating cervical spinal cord injury without fracture and dislocation can obtain satisfactory results in restoring nerve function, alleviating pain and improving daily behavior, but single open-door laminoplasty has the advantages of less trauma and low incidence of complications.

Cervical Myelopathy: An Update on Posterior Decompression

STUDY DESIGN

This was a narrative review.

OBJECTIVE

The aim was to discuss current methods and review updated outcome studies regarding posterior decompression in the management of cervical myelopathy.

SUMMARY OF BACKGROUND DATA

Progressive myelopathy in the cervical segments is an indication for urgent surgical management. Although nonoperative treatment is an option in mild to moderate cases, the majority of patients will experience deterioration in neurological function requiring surgical decompression.

METHODS

A review of the literature was performed using PubMed to provide updated information regarding posterior cervical decompression in the management of myelopathy.

RESULTS

There are numerous studies comparing outcome data between cervical laminectomy and fusion with laminoplasty. While each technique has advantages and disadvantages, both provide adequate decompression and good long-term outcomes in patients meeting appropriate criteria.

CONCLUSIONS

Posterior decompression is an important approach for spine surgeons to have in their toolkits when treating cervical myelopathy.

A Single Vertebral Surgical Approach for Spinal Extradural Meningeal Cysts Spanning Multiple Vertebral Segments by Auxiliary Neuroendoscope

BACKGROUND

Spinal extradural meningeal cysts (SEMCs) are rare lesions, especially those spanning multiple vertebral segments, and the surgical strategy has remained controversial. In the present study, we have described the outcomes of 4 patients with SEMCs treated with dural defect repair alone assisted by neuroendoscopy.

METHODS

From January 2018 to January 2020, 4 patients with SEMCs spanning multiple vertebral segments had undergone single-vertebral laminectomy or hemilaminectomy.

RESULTS

The SEMCs in all 4 patients had spanned multiple vertebral segments, from T11 to L2. Using magnetic resonance imaging, the location of the dural defect was predicted correctly for 3 patients. Single-vertebral laminectomy was used in 2 patients and single-vertebral hemilaminectomy in 2 patients. Intraoperatively, the entire cyst, including the upper pole, lower pole, and middle segment of the cyst, was explored using neuroendoscopy. In each patient, only 1 dural defect was found, which had been located in the middle segment of the cyst (T12-L1). All cyst dural defects had been sutured under a microscope. In all cases, the cyst wall was not removed. Postoperatively, the symptoms for all the patients had improved significantly, and subsequent magnetic resonance imaging studies showed obvious cyst regression. During the follow-up period of 15-44 months, no recurrence was observed.

CONCLUSIONS

For SEMCs spanning multiple vertebral segments, dural defect repair without cyst wall resection through single-vertebral hemilaminectomy or laminectomy can be effective. Intraoperative neuroendoscopy can assist, not only in finding the dural defect, but also in avoiding the omission of multiple dural defects as much as possible.

Describing the spine surgery learning curve during the first two years of independent practice

Retrospective cohort studyTo characterize the learning curve of a spine surgeon during the first 2 years of independent practice by comparing to an experienced colleague. To stratify learning curves based on procedure to evaluate the effect of experience on surgical complexity.The learning curve for spine surgery is difficult to quantify, but is useful information for hospital administrators/surgical programs/new graduates, so appropriate expectations and accommodations are considered.Data from a retrospective cohort (2014-2016) were analyzed at a quaternary academic institution servicing a geographically-isolated, mostly rural area. Procedures included anterior cervical discectomy and fusion, posterior cervical decompression and stabilization, single and 2-level posterior lumbar interbody fusion, lumbar discectomy, and laminectomy. Data related to patient demographics, after-hours surgery, and revision surgery were collected. Operative time was the primary outcome measure, with secondary measures including cerebrospinal fluid leak and early re-operation. Time periods were stratified into 6 month quarters (quarter [Q] 1-Q4), with STATA software used for statistical analysis.There were 626 patients meeting inclusion criteria. The senior surgeon had similar operative times throughout the study. The new surgeon demonstrated a decrease in operative time from Q1 to Q4 (158 minutes-119 minutes, P < .05); however, the mean operative time was shorter for the senior surgeon at 2 years (91 minutes, P < .05). The senior surgeon performed more revision surgeries (odds ratio [OR] 2.5 [95% confidence interval [CI] 1.7-3.6]; P < .001). Posterior interbody fusion times remained longer for the new surgeon, while laminectomy surgery was similar to the senior surgeon by 2 years. There were no differences in rates of cerebrospinal fluid leak (OR 1.2 [95% CI 0.6-2.5]; P > .05), nor reoperation (OR 1.16 [95% CI 0.7-1.9]; P > .05) between surgeons.A significant learning curve exists starting spine practice and likely extends beyond the first 2 years for elective operations.

Placement of surgical spinal cord stimulation (SCS) leads using spinal process splitting laminotomy (SPSL): Technical note

OBJECTIVE

Spinal Cord Stimulation (SCS) has become an established method within the therapy of chronic pain allowing for significant pain relief. Surgical leads usually have to be implanted via a surgical procedure involving uni- or bilateral muscle detachment and partial laminectomy.

METHODS

We present the application of a novel minimal invasive microsurgical approach for lead placement which combines the beneficial advantages of anatomical midline lead placement whilst preserving the midline structures, avoiding muscle detachments and thus ensuring spinal stability: spinal process splitting laminotomy (SPSL).

CONCLUSION

The spinal process splitting laminotomy (SPSL) technique can be successfully applied to introduce the surgical leads for spinal cord stimulation.

Comparison of the clinical efficacy of percutaneous transforaminal endoscopic discectomy and traditional laminectomy in the treatment of recurrent lumbar disc herniation

A few years ago, percutaneous transforaminal endoscopic discectomy (PTED) began to prevail in clinical treatment of recurrent lumbar disc herniation (RLDH), whereas traditional laminectomy (TL) was treated earlier in RLDH than PTED. This study aimed to compare the clinical efficacy of PTED and TL in the treatment of RLDH.Between November 2012 and October 2017, retrospective analysis of 48 patients with RLDH who were treated at the Cancer Hospital, Chinese Academy of Sciences, Hefei and Department of Orthopaedics, Second Affiliated Hospital of Anhui Medical University. Perioperative evaluation indicators included operation time, the intraoperative blood loss, length of incision and hospitalization time. Clinical outcomes were measured preoperatively, and at 1 days, 3 months, and 12 months postoperatively. The patients' lower limb pain was evaluated using Oswestry disability index (ODI) and visual analog scale (VAS) scores. The ODI is the most widely-used assessment method internationally for lumbar or leg pain at present. Every category comprises 6 options, with the highest score for each question being 5 points. higher scores represent more serious dysfunction. The VAS is the most commonly-used quantitative method for assessing the degree of pain in clinical practice. The measurement method is to draw a 10 cm horizontal line on a piece of paper, 1 end of which is 0, indicating no pain, which the other end is 10, which means severe pain, and the middle part indicates different degree of pain.Compared with the TL group, the operation time, postoperative bed-rest time, and hospitalization time of the PTED group were significantly shorter, and the intraoperative blood loss was also reduced. These differences were statistically significant (P < .01). There were no significant differences in VAS or ODI scores between the two groups before or after surgery (P > .05).PTED and TL have similar clinical efficacy in the treatment of RLDH, but PTED can shorten the operation time, postoperative bed-rest time and hospitalization time, and reduce intraoperative blood loss, so the PTED is a safe and effective surgical method for the treatment of RLDH than TL, but more randomized controlled trials are still required to further verify these conclusions.

Anterior Atlas Fracture After C1 Laminectomy Which Was Successfully Treated by Brace Therapy: A Case Report

CASE

We report a case of a 67-year-old male patient who underwent a C1 laminectomy with laminoplasty at C2-3 because of cervical ossification of the posterior longitudinal ligament. At 6 weeks after surgery, neck pain occurred after minor trauma without neurological deterioration. Computed tomography (CT) demonstrated C1 anterior atlas fracture with a 3-mm gap. After a 3-month brace therapy using a Philadelphia collar, the patient's neck pain disappeared with complete bone union according to the CT.

CONCLUSION

Among 14 cases that were reported previously, none of the adult patients achieved bone union by brace therapy. Therefore, this is the only case report in which bone union could be achieved by brace therapy.

Cement-Augmented and Dual-Headed Posterior Screw Reconstruction After Corpectomy for Metastatic Tumor Resection

BACKGROUND

Metastatic spinal tumors have a well-documented deleterious effect on the overall strength of the bony spine. Surgical interventions must address not only removal of the tumor itself, but the integrity of reconstructive hardware constructs as well.

METHODS

We present a series of 8 patients with metastatic spine tumors who were successfully treated with tumor resection and reconstruction of residual 3-column defect with cement-augmented fenestrated pedicle screws and dual-rod posterior stabilization.

RESULTS

All patients demonstrated resolution of their presenting neurologic symptoms.

CONCLUSIONS

This series supports the use of the aforementioned constructs in conjunction to provide added stability and reduce hardware failure when treating a diversity of spinal tumors.

Universal approach for full endoscopic decompression and percutaneous transpedicular fixation of the lumbar spine: A medial central approach (ACM)

Cohort study.This study aimed to determine the effectiveness of the universal approach of full endoscopy and percutaneous transpedicular fixation via a medial central approach (ACM) performed to surgically treat patients with lumbar degenerative surgical pathologies.Alternatives to interventionist treatments available to patients with lumbar degenerative surgical pathologies are related to recovery from minimally invasive surgery. Considering this, full endoscopic spinal decompression (full endoscopy) and percutaneous transpedicular fixation via an ACM represent advances in neurosurgical procedures, in particular, spinal surgery. Thus, the introduction of endoscopic and minimally invasive surgeries for the lumbar region has become 1 of the most important advances in modern surgery.A cohort of 79 patients undergoing full endoscopy and percutaneous transpedicular fixation was evaluated 6 times in 1 year. Pain intensity was measured using the visual analog scale (VAS), and lumbar functionality was measured using the Oswestry Disability Index (ODI). Six evaluations were performed: before surgery and on discharge after surgery as well as at 1, 3, 6, and 12 months after surgery.Before the ACM was applied, the VAS pain score was 8.52. At 11 hours post-surgery, the pain score reduced to 2.59 points (a difference of 5.73 points; P = 0.001). Of the 10 ODI domains evaluated, a difference was found between the period prior to surgery and 1 month later (P < 0.01).The universal approach to full endoscopy and lumbar percutaneous transpedicular fixation via an ACM is highly effective for patients with lumbar surgical degenerative pathologies.

Retro-Odontoid Pseudotumor Without Radiographic Instability with Congenital C1 Assimilation and C2-C3 Fusion: A Case Report

CASE

The authors present a case of retro-odontoid pseudotumor (ROP) with congenital C1 assimilation and C2-C3 block vertebra without radiological instability who presented with cervical myelopathy with spastic quadriparesis. The patient was managed with occipitocervical fusion and C1 laminectomy. She had rapid neurological recovery in 3 months postoperatively and at 2 years had complete resolution of the retro-odontoid mass.

CONCLUSION

C1 assimilation without apparent radiographic instability as a cause of ROP is underappreciated. This case report and review of literature highlight that C1 assimilation and C2-C3 fusion can lead to ROP even in the absence of apparent radiographic instability with posterior atlantoaxial fusion alone providing good results.

Nivolumab as adjuvant treatment for a spinal melanocytoma: A case report

RATIONALE

Meningeal melanocytoma is a rare benign melanocytic tumor of the central nervous system. We report for the first time a case of meningeal melanocytoma treated with immunotherapy.

PATIENT CONCERNS

A 70-year-old man with no medical history was admitted to the Emergency Room. He suffered from a motor and sensory deficit in his left lower limb and a bilateral upper arm neuralgia.

DIAGNOSES

A contrast-enhanced magnetic resonance imaging (MRI) was performed. It showed a C7-T1 bleeding intramedullary tumor. Laminectomy was decided and performed. The results of the pathologic examination showed a melanocytic tumor harboring GNAQ mutation. Meningeal melanocytoma was the final diagnosis.

INTERVENTIONS

The patient was treated with 10 radiotherapy sessions and 6 cycles of nivolumab. A year later, the patient experienced neuralgia again with severe pain and an increasing sensory motor deficit. He underwent a second surgery that was incomplete. As the tumor kept growing, he received temozolomide. But the 6th cycle had to be interrupted due to bedsore infection in the hip area.

OUTCOMES

Disease progression finally led to the patient's death 3 years after diagnosis.

LESSONS

This case report is the first about a patient with meningeal melanocytoma treated with immunotherapy. Treatment based on biomolecular mutations will probably change spinal melanocytoma therapeutic approach in the next few years.

Symptomatic perineural cyst after spontaneous subarachnoid hemorrhage: A case report

RATIONALE

Tarlov or perineurial cysts are nerve root lesions often found in the sacral region. Most perineural cysts (PCs) remain asymptomatic throughout a patient's life. While their pathogenesis is still unclear, trauma resulting in hemorrhaging into subarachnoid space has been put forward as a possible cause of these cysts. Recently, we worked with a patient experiencing symptomatic PCs after spontaneous subarachnoid hemorrhage.

PATIENT CONCERNS

A 45-year-old man had a coil embolization procedure performed after being diagnosed with a subarachnoid hemorrhage from a ruptured anterior communicating artery. His symptoms were relieved after the procedure, but 7 days later he reported worsening pain in the left perineal area. The pain was intermittent at its onset and exacerbated by sitting, walking, and coughing.

DIAGNOSES

Two weeks after the embolization procedure, a lumbar spine MRI revealed 2 PCs at the S1 and S2 level affecting the left S2 root with high signal intensity in T2 and T1 images, suggestive of bleeding within the cyst.

INTERVENTIONS

We operated using a posterior approach. Cyst fenestration was done after S1 laminectomy. We aspirated approximately 1 cc of old blood.

OUTCOMES

His pain was relieved immediately after cyst removal and no neurologic deterioration occurred during the postoperative period.

LESSONS

Subarachnoid hemorrhage can be the source of the development of pain from asymptomatic PCs, making them symptomatic. Surgical extirpation is 1 treatment option for these symptomatic PCs.

Effect of Ventral vs Dorsal Spinal Surgery on Patient-Reported Physical Functioning in Patients With Cervical Spondylotic Myelopathy: A Randomized Clinical Trial

IMPORTANCE

Cervical spondylotic myelopathy is the most common cause of spinal cord dysfunction worldwide. It remains unknown whether a ventral or dorsal surgical approach provides the best results.

OBJECTIVE

To determine whether a ventral surgical approach compared with a dorsal surgical approach for treatment of cervical spondylotic myelopathy improves patient-reported physical functioning at 1 year.

DESIGN, SETTING, AND PARTICIPANTS

Randomized clinical trial of patients aged 45 to 80 years with multilevel cervical spondylotic myelopathy enrolled at 15 large North American hospitals from April 1, 2014, to March 30, 2018; final follow-up was April 15, 2020.

INTERVENTIONS

Patients were randomized to undergo ventral surgery (n = 63) or dorsal surgery (n = 100). Ventral surgery involved anterior cervical disk removal and instrumented fusion. Dorsal surgery involved laminectomy with instrumented fusion or open-door laminoplasty. Type of dorsal surgery (fusion or laminoplasty) was at surgeon's discretion.

MAIN OUTCOMES AND MEASURES

The primary outcome was 1-year change in the Short Form 36 physical component summary (SF-36 PCS) score (range, 0 [worst] to 100 [best]; minimum clinically important difference = 5). Secondary outcomes included 1-year change in modified Japanese Orthopaedic Association scale score, complications, work status, sagittal vertical axis, health resource utilization, and 1- and 2-year changes in the Neck Disability Index and the EuroQol 5 Dimensions score.

RESULTS

Among 163 patients who were randomized (mean age, 62 years; 80 [49%] women), 155 (95%) completed the trial at 1 year (80% at 2 years). All patients had surgery, but 5 patients did not receive their allocated surgery (ventral: n = 1; dorsal: n = 4). One-year SF-36 PCS mean improvement was not significantly different between ventral surgery (5.9 points) and dorsal surgery (6.2 points) (estimated mean difference, 0.3; 95% CI, -2.6 to 3.1; P = .86). Of 7 prespecified secondary outcomes, 6 showed no significant difference. Rates of complications in the ventral and dorsal surgery groups, respectively, were 48% vs 24% (difference, 24%; 95% CI, 8.7%-38.5%; P = .002) and included dysphagia (41% vs 0%), new neurological deficit (2% vs 9%), reoperations (6% vs 4%), and readmissions within 30 days (0% vs 7%).

CONCLUSIONS AND RELEVANCE

Among patients with cervical spondylotic myelopathy undergoing cervical spinal surgery, a ventral surgical approach did not significantly improve patient-reported physical functioning at 1 year compared with outcomes after a dorsal surgical approach.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02076113.

Comparison of the surgeries for the ossification of the posterior longitudinal ligament-related cervical spondylosis: A PRISMA-compliant network meta-analysis and literature review

OBJECTIVE

We designed and performed a network meta-analysis to compare the clinical outcomes among the 5 surgeries-anterior cervical corpectomy and fusion (ACCF), anterior controllable antedisplacement fusion (ACAF), laminoplasty (LP), laminectomy (LC), and posterior decompression with instrumented fusion (PDF)-for patients with cervical spondylosis related to the ossification of the posterior longitudinal ligament (OPLL).

METHODS

Databases, including PubMed, EMBASE, Cochrane Library, Google Scholar, and Web of Science (firstly available-2019) were selected for literature search. We performed a network meta-analysis with the included studies. A Newcastle-Ottawa scale was employed to assess the study quality of the included studies.

RESULTS

Total 23 studies with 1516 patients were included in our analysis. We found that ACCF achieved the most improvement in the Japanese Orthopaedic Association Scores and excellent and good recovery rate, ACAF achieved the best improvement of the improvement rate and lordosis. LP got the best operative time and blood loss.

CONCLUSIONS

Our results suggested that both anterior (ACCF and ACAF) and posterior (LP, LC, and PDF) procedures have their strengths and weaknesses. Clinicians need to select the most appropriate surgery with a comprehensive consideration of the clinical condition of each patient with OPLL-related cervical spondylosis.

Postoperative spinal epidural hematoma in a biportal endoscopic spine surgery

ABSTRACT

Biportal endoscopic spine surgery (BESS) is extending its application to most kind of spine surgeries. Postoperative spinal epidural hematoma (POSEH) is one of the major concerns of this emerging technique. Through this study we aim to investigate the incidence of POSEH in BESS comparing to a conventional spine surgery (CSS).The patients who underwent a non-fusion decompressive spine surgery due to degenerative lumbar spinal stenosis (LSS) or herniated lumbar disc (HLD) or both between January 2015 and March 2019 were reviewed retrospectively. The incidence of clinical POSEH that demanded a revision surgery for hematoma evacuation was compared between CSS and BESS. As a second endpoint, the morphometric degree of POSEH was compared between the two groups. The maximal compression of cauda equina by POSEH was measured by 4 grade scale at the T2 axial image and the neurological state was evaluated by 5 grade scale. The indication of hematoma evacuation was more than hG3 with more than nG1. As a subgroup analysis, risk factors of POSEH in BESS were investigated.The 2 groups were homogenous in age, sex, number and level of operated segments. There was significant difference in the incidence of symptomatic POSEH as 2/142 (1.4%) in CSS and 8/95 (8.4%) in BESS (P = .016). The radiological thecal sac compression by hematoma was hG1 65 (61.3%), hG2 35 (33.0%), hG3 5 (4.7%), hG4 1 (0.9%) cases in CSS and hG1 33 (39.8%), hG2 25 (30.1%), hG3 22 (26.5%), hG4 3 cases (3.6%) in BESS. The difference was significant (P < .001). In BESS subgroup analysis, the risk factor of high grade POSEH was bilateral laminectomy (OR = 8.893, P = .023).The incidence of clinical and morphometric POSEH was higher in BESS. In BESS, POSEH developed more frequently in bilateral laminectomy than unilateral laminectomy.

Influence of peri-incisional epaxial muscle infiltration with bupivacaine pre- or post-surgery on opioid administration in dogs undergoing thoraco-lumbar hemilaminectomy

This study investigated the influence of bupivacaine infiltration before or after hemilaminectomy on peri-operative opioid requirement in dogs. Thirty dogs undergoing T3-L3 hemilaminectomy were randomly assigned to receive peri-incisional infiltration of bupivacaine 2 mg/kg into the epaxial muscles before surgery (Group A), at wound closure (Group B), or no infiltration (Group C). Anaesthesia comprised dexmedetomidine 4 mcg/kg and methadone 0.3 mg/kg IV (premedication), alfaxalone IV (induction), and isoflurane in oxygen (maintenance). All dogs received meloxicam SC/PO prior to induction of general anaesthesia. Response to surgery, defined as a change in autonomic physiological variables >20% above baseline, was treated with fentanyl 2.5 mcg/kg boluses, followed by a continuous rate infusion of fentanyl at 5 mcg/kg/h. The Glasgow Composite Pain Score-Short Form (GCPS-SF) was performed before premedication and at regular intervals until 24 h postoperatively. Methadone 0.2 mg/kg analgesia was given IV if GCPS-SF was ≥5/20. Number of intraoperative, postoperative and total analgesic interventions were recorded. Analgesic interventions were analysed using a chi-squared test using a Pocock approach and statistical significance was set at P < 0.029. The number of intra-operative analgesic interventions in Group A (median, 0; range, 0-2), was significantly lower than in Group B (median, 3; range, 0-5) and Group C (median, 3; range, 0-5; P = 0.019). Regarding postoperative interventions, there were significantly fewer in Group A (median, 0; range, 0-1) and Group B (median, 0; range, 0-1) than in Group C (median, 1; range, 0-2; P = 0.047). Group A (median, 0; range, 0-3), had significantly fewer total analgesic interventions than Group B (median, 3; range, 0-6) and Group C (median, 4; range, 1-7; P = 0.014). Bupivacaine reduced peri-operative opioid administration and pre-surgical peri-incisional infiltration yielded the greatest benefit.

The effect of preoperative degenerative spondylolisthesis on postoperative outcomes of degenerative lumbar spinal stenosis: A single-center cohort study protocol

BACKGROUND

Most degenerative lumbar spinal stenosis (DLSS) patients primitively received the conservative treatment to control symptoms. In order to develop an optimal surgical treatment strategy, it is very significant to understand how the degenerative lumbar spondylolisthesis (DS) affects the effect of decompression in the DLSS. Thus, the aim of this current study was to explore whether the concomitant DS would affect the effect of decompression alone in the patients with DLSS.

METHODS

The current study was carried out at our hospital and it was approved through our institutional review committee of General Hospital of Ningxia Medical University. During the period from January 2015 to December 2017, in our study, we identified consecutive patients who received the minimally invasive laminectomy to treat the DLSS. The inclusion criterion included radicular leg pain or neurogenic claudication with the neurological symptoms associated with DLSS syndrome, magnetic resonance imaging of the lumbar spine reveals at least 1 level of serious stenosis, the conservative treatment failed for at least 3 months, and patients agreed to provide the postoperative details. The major outcomes of this present research was Oswestry Disability Index. Secondary outcomes of this current study involved visual analog score, short form-36, surgical revision rate as well as complications.

RESULTS

We assumed that previous DS possessed a negative effect on the postoperative results of the DLSS patients.

TRIAL REGISTRATION

researchregistry5943.

A new classification for spinal epidural hematoma following microendoscopic decompressive laminotomy: A prospective clinical and magnetic resonance imaging study of 245 patients

OBJECTIVE

The aim of this study was to develop a new radiological classification system for postoperative spinal epidural hematoma (SEH) using magnetic resonance imaging (MRI) and to determine the correlation of this classification system with clinical and radiological outcomes.

METHODS

This prospective study included a total of 245 consecutive patients (126 females, 119 males; mean age=72 years; age range=39-91 years) with single level spinal stenosis who were treated by microendoscopic decompressive laminotomy (MEDL). MRI was performed for all patients 24 hours postoperatively and at 12 months. SHEs were categorized into four grades using our new MRI-based classification system based on the measurement of dural sac area: Grade A, small hematoma with a round shape; grade B, small hematoma that show no round shape; grade C, moderate hematoma; grade D: severe hematoma. Patients were then divided into four groups according to their hematoma grades, Group A, 107 patients with grade A hematomas; group B, 47 with grade B; group C, 67 with grade C; group D, 24 with grade D. Also, patients who had neurological deterioration or who pain resistant to medical treatment were treated surgically, and those were assigned to group H+(14 patients). The study, therefore, contained five groups. Clinical evaluation was done using Japanese Orthopaedic Association (JOA) score preoperatively and at 12 months postoperatively.

RESULTS

No significant difference existed among groups in the preoperative median measurement of the dural sac area, which were 0.90 cm2 in group A, 0.80 cm2 in group B, 0.70 cm2 in group C, 1.1 cm2 in group D, and 0.80 cm2 in group H+ (p=0.076). At the postoperative 12-month measurement, no significant difference was noted among groups A (2.05 cm2), B (1.80 cm2 ), and H+ (1.90cm2) (A vs B: p=0.891, A vs H+: p=0.089, B vs H +: p=0.933). The measurements were greater in groups A and B than in groups C and D (p<0.05). Also, larger dural sac areas were determined in group H+ (1.90cm2) compared to Groups C (1.80 cm2) and D (1.60 cm2) but the difference reached no statistical significance (p=0.078). In preoperative JOA scores, there were no significant differences among groups (p>0.05). At 12-month JOA scores, no significant difference was observed between groups A and B (p=0.061) and between groups C and D (p=0.511). The scores were higher in groups A and B than in groups C and D (p<0.05).

CONCLUSION

It seems that the narrower the preoperative dural sac area, the better the clinical symptoms of the patients with SEHs based on our new MRI-based classification system. This classification may be useful to predict the clinical status of these patients at one-year follow-up.

LEVEL OF EVIDENCE

Level IV, Diagnostic study.

Schmorl node induced multiple radiculopathy: A rare case report

RATIONALE

We report a case of Schmorl node induced multiple radiculopathy.

PATIENT CONCERNS

A 70-year-old female patient complained of lower back pain in the left leg accompanied by numbness and weakness.

DIAGNOSIS

Radiographs showed obvious osteoporosis in the lumbar vertebrae. Computed tomography demonstrated a hole in the upper posterior half of the L2 vertebral body. Magnetic resonance imaging of the lumbar spine revealed a herniated disc involving a protrusion at the posterior wall of the L2 vertebral body, which was present in the left lateral and dorsal epidural spaces. There was significant lumbar stenosis at the L2 vertebral body secondary to dural sac compression due to the mass.

INTERVENTION

Left-sided hemilaminectomy was performed at L2 with screw fixation at L1-3. Intraoperatively, the severely ruptured disc compression in the dural sac and nerve root was removed.

OUTCOMES

The patient's leg pain was immediately resolved, and her back pain was reduced. The patient recovered normal motor function at 20 days after surgery.

LESSONS

A Schmorl node can progress and break through the lumbar vertebral body, resulting in nerve compression. A large proximal herniated mass can cause distal multiple radiculopathy. Therefore, this special case of Schmorl node with multiple radiculopathy should be treated by removing the proximal herniated nucleus pulposus from the vertebral body.

Bilateral thoracic disc herniation with abdominal wall paresis: a case report

We present a rare case of a patient initially presenting with unilateral abdominal wall bulging and radicular pain caused by a lateral disc herniation at Th11/12, later suffering from a hernia recurrence with bilateral disc prolapse and motor deficits. The patient underwent sequesterectomy via a right hemilaminectomy at Th11, and after 8 weeks, a bilateral sequesterectomy with semirigid fusion Th11/12 was performed. Unilateral motor deficits at the thoracic level have been discussed in case reports; a bilateral disc protrusion with abdominal wall bulging occurring as a recurrent disc herniation has never been described before.

General Anaesthesia Versus Regional Anaesthesia For Lumbar Laminectomy: A Review Of The Modern Literature

BACKGROUND

Lumbar spine surgery can be performed using different anaesthetic techniques such as general endotracheal anaesthesia (GA) or spinal-based regional anaesthesia (RA). Few of the studies have been done to compare the outcomes of spinal anaesthesia versus general anaesthesia for lumbar laminectomies as both having some advantages as well as disadvantages but still it is controversial. The objective of current study is to make a comprehensive review of literature for comparing the outcomes of lumbar laminectomy performed under general anaesthesia versus spinal anaesthesia.

METHODS

Literature search was performed by using PubMed, Google scholar and bibliography of related articles. To compare groups of general anaesthesia versus spinal anaesthesia, the variables focused were mean heart rate (HR), mean arterial pressure (MAP), blood loss during surgery, duration of surgery, post-operative anaesthesia care unit (PACU) time, postoperative narcotic use/pain scale, post-operative urinary retention, and post-operative nausea/vomiting.

RESULTS

Data of eleven studies were presented in current article, of these five were randomized controlled trials, three case-controls and four were retrospective cohort studies. 5/8 studies reported that SA group having more hemodynamic stability with postoperative outcomes as compared to GA. Likewise, majority of reviewed studies (7/8) reported better pain control or decreased requirement of analgesics in SA group. Additionally, more than half of the reviewed studies (5/8) reported lower incidence of postoperative nausea and vomiting among patients of SA group..

CONCLUSIONS

The current study concluded that SA has better outcomes than GA in terms of hemodynamic stability and decrease postoperative adverse effects. So special attention should be paid for SA as an alternative to GA for lumbar laminectomy.

Surgical Outcomes in Selective Laminectomy and Conventional Double-Door Laminoplasty for Cervical Spondylotic Myelopathy

Several postoperative problems have been reported in conventional cervical laminoplasty (C-LAMP), such as loss of cervical curvature, sagittal imbalance, and loss of range of motion (ROM). Selective laminectomy (S-LAM) is a less invasive procedure that may prevent the problems associated with conventional C-LAMP. In this study, the authors prospectively compared neurological outcomes and radiological parameters in C-LAMP and S-LAM for the treatment of cervical spondylotic myelopathy. Fifty-three patients were enrolled, with 25 patients receiving conventional double-door C-LAMP and 28 patients receiving S-LAM. Measured outcomes included operative time, intraoperative blood loss, Japanese Orthopaedic Association score for neurological recovery, cervical sagittal alignment at C2-7, cervical sagittal vertical axis from occiput to C7, C7 slope, and cervical ROM at C2-7. No difference was found in operative time, whereas intraoperative blood loss was significantly less in the S-LAM group (P<.05). No significant difference in neurological recovery was found between the 2 groups. The postoperative C2-7 angle was significantly smaller (P<.05) and cervical sagittal vertical axis greater (P<.01) in the C-LAMP group. Postoperative ROM at C2-7 was greater (P<.01) in the S-LAM group. In the CLAMP group, postoperative kyphotic change was greater in patients with high C7 slope. However, in the S-LAM group, postoperative sagittal alignment was preserved even in patients with high C7 slope. Postoperative cervical alignment, sagittal balance, and cervical ROM were better preserved in the S-LAM group compared with the C-LAMP group. Selective laminectomy is an effective, minimally invasive method for cervical spondylotic myelopathy with spinal cord compression at limited levels. [Orthopedics. 2020;43(4);e311-e315.].

Percutaneous pedicle screw fixation combined with transforaminal endoscopic spinal canal decompression for the treatment of thoracolumbar burst fracture with severe neurologic deficit: A case report

RATIONALE

The most common fractures of the spine are associated with the thoracolumbar junction (T10-L2). And burst fractures make up 15% of all traumatic thoracolumbar fractures, which are often accompanied by neurological deficits and require open surgeries. Common surgeries include either anterior, posterior or a combination of these approaches. Here, we report the first attempt to treat thoracolumbar burst fracture (TLBF) with severe neurologic deficits by percutaneous pedicle screw fixation (PPSF) and transforaminal endoscopic spinal canal decompression (TESCD).

PATIENT CONCERNS

A 46-year-old Chinese woman suffered from severe lower back pain with grade 0 muscle strength of lower limbs, without any sensory function below the injury level, with an inability to urinate or defecate after a motor vehicle accident. Imaging studies confirmed that she had Magerl type A 3.2 L1 burst fracture.

DIAGNOSES

Burst fracture at L1.

INTERVENTIONS

The patient underwent PPSF at the level of T12 to L2, but her neurological function did not fully recover after the operation. One week after the injury, we performed TESCD on her.

OUTCOMES

There was an immediate improvement in her neurological function in just 1 day after 2-stage operation. During the 6-month follow-up period, her neurological functions gradually recovered, and she was able to defecate and urinate. At the last follow-up visit, her spinal cord function was assessed to be at Frankel grade D.

LESSONS

PPSF plus TESCD can achieve complete spinal cord decompression, promote neurological recovery, and is therefore an effective method for the treating lumbar burst fractures with severe neurologic deficits.

Transdural Approach to Resection of Intraspinal Extradural Ventral Cysts in the Lumbar Spine

BACKGROUND

Intraspinal extradural ventral cysts in the lumbar spine can cause back pain and neurological deficits of the lower extremities. For the resection of this type of space-occupying lesion, the transdural approach has not been reported in the literature.

CASE DESCRIPTION

A 66-year-old man presented, suffering from progressive radiation pain of his bilateral lower extremities. Imaging examination revealed a cystic lesion in ventral side of lumbar spinal canal. We conducted the excision of the cyst with the transdural approach. The symptoms of the patient disappeared immediately after the operation and recurrence of the symptoms has not been observed in the 3-month follow-up.

CONCLUSIONS

This operation approach is safe and effective. Compared with the previous surgical approach reported in the literature, by this approach surgeons could achieve less injury, shorter operation time, and the same surgical outcomes in the short term. Therefore, we would like to present this approach to provide an alternative to deal with similar lesions.

Are degenerative spondylolisthesis and further slippage postoperatively really issues in spinal stenosis surgery?

Background and aims Opinions diverge concerning the prognostic importance of preoperative degenerative spondylolisthesis in patients with lumbar spinal stenosis, as well as the significance of further slippage post-operatively following decompression alone. However, a slip is only one among several factors related to the topic, e.g. duration and intensity of back and leg pain, pre-operative walking ability, number of levels operated and not least the experience of the surgeon. Our aim was to take all of the above-mentioned factors into consideration when analysing the patients' clinical outcome, reported as Change in back pain, Change in leg pain, Overall satisfaction and Change in walking ability, with special emphasis on the possible importance of pre- and/or post-operative degenerative spondylolisthesis. Methods We studied 200 consecutive patients, mean follow-up time 81 months (range 62-108). Before treatment and on the follow-up occasion all patients answered the SF-36 questionnaire and assessed their back and leg pain on a visual analogue scale (VAS). At follow-up the patients were asked about possible changes in back and leg pain (completely free, much better, somewhat better, unchanged, somewhat worse, much worse) and whether they were; satisfied with the outcome, in doubt or not satisfied. Before treatment and at follow-up the presence or not of degenerative spondylolisthesis was determined in the lateral view on a plain X-ray or MRI. By use of a microsurgical technique decompression was achieved in all patients by bilateral laminotomy not sparing the midline ligaments, irrespective of a degenerative spondylolisthesis or not. Eight surgeons with different surgical experience performed the operations. Four separate multivariate analyses were conducted, one for each clinical outcome. The Lasso method was used for variable selection and multiple imputation was applied to handle missing values. Results At follow-up 78.5% of the patients were completely satisfied with the outcome. Minimal clinical important difference (MCID) was achieved for 69% of the patients. Before surgery 28 patients were able to walk more than 1 km compared to 111 at follow-up. The reoperation rate at 6.8 years was 12% further decompressions and 2.5% fusions at the index level. Post-operative slippage was equally common in patients with and without a preoperative slip (around 30%). There were no notable differences in outcome in patients with and without a preoperative slip and no effect of further slippage at the index or another level post-operatively. Nor could the statistical analysis show any of the other covariates (age, gender, duration and intensity of back and leg pain, pre-operative walking ability or number of levels operated) to be of statistically significant importance for predicting the outcome. In the univariate statistical analysis differences were found between the patients of individual surgeons regarding satisfaction, pain improvement, and reoperation rates in favour of surgical experience, which were, however, not statistically significant in the multivariate analysis. Conclusions None of the covariates, including pre-operative spondylolisthesis and further slippage post-operatively, were statistically significant for predicting the clinical outcome. Implication Our results provide no evidence for adding fusion to the decompression.

A Review of Techniques, Time Demand, Radiation Exposure, and Outcomes of Skin-anchored Intraoperative 3D Navigation in Minimally Invasive Lumbar Spinal Surgery

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To describe our technique for and evaluate the time demand, radiation exposure and outcomes of skin-anchored intraoperative three-dimensional navigation (ION) in minimally invasive (MIS) lumbar surgery, and to compare these parameters to 2D fluoroscopy for MI-TLIF.

SUMMARY OF BACKGROUND DATA

Limited visualization of anatomic landmarks and narrow access corridor in MIS procedures result in greater reliance on image guidance. Although two-dimensional fluoroscopy has historically been used, ION is gaining traction.

METHODS

Patients who underwent MIS lumbar microdiscectomy, laminectomy, or MI-TLIF using skin-anchored ION and MI-TLIF by the same surgeon using 2D fluoroscopy were selected. Operative variables, radiation exposure, and short-term outcomes of all procedures were summarized. Time-demand and radiation exposure of fluoroscopy and ION for MI-TLIF were compared.

RESULTS

Of the 326 patients included, 232 were in the ION cohort (92 microdiscectomies, 65 laminectomies, and 75 MI-TLIFs) and 94 in the MI-TLIF using 2D fluoroscopy cohort. Time for ION setup and image acquisition was a median of 22 to 24 minutes. Total fluoroscopy time was a median of 10 seconds for microdiscectomy, 9 for laminectomy, and 26 for MI-TLIF. Radiation dose was a median of 15.2 mGy for microdiscectomy, 16.6 for laminectomy, and 44.6 for MI-TLIF, of this, 93%, 95%, and 37% for microdiscectomy, laminectomy, and MI-TLIF, respectively were for ION image acquisition, with the rest attributable to the procedure. There were no wrong-level surgeries. Compared with fluoroscopy, ION for MI-TLIF resulted in lower operative times (92 vs. 108 min, P < 0.0001), fluoroscopy time (26 vs. 144 s, P < 0.0001), and radiation dose (44.6 vs. 63.1 mGy, P = 0.002), with equivalent time-demand and length of stay. ION lowered the radiation dose by 29% for patients and 55% for operating room personnel.

CONCLUSION

Skin-anchored ION does not increase time-demand compared with fluoroscopy, is feasible, safe and accurate, and results in low radiation exposure.

LEVEL OF EVIDENCE

3.

Thoracic gout tophus with abdominal wall protrusion: A case report

RATIONALE

A patient presented the abdominal wall protrusion due to tophaceous gout of the spine. Similar cases were not reported in the literature. This study aimed to report a case of tophaceous gout of the spine with abdominal wall protrusion.

PATIENT CONCERNS

A 38-year-old male patient had a 10-year history of gout and hyperuricemia. He complained of back pain and abdominal wall protrusion.

DIAGNOSES

The patient was diagnosed with tophaceous gout of the spine with abdominal wall weakness caused by T11 nerve root compression.

INTERVENTIONS

A semi-lamina decompression was performed at T11-T12. The pathological examination of the specimen demonstrated tophaceous gout of the spine.

OUTCOMES

After the surgery, the patient's back pain was completely relieved and the abdominal wall weakness significant improved.

LESSONS

This case highlighted that axial gout could mimic thoracic disk herniation clinically. The abdominal wall weakness might also be due to single T11 nerve compression by the tophaceous gout of the spine. In patients with a history of gout, axial gout should be considered as one of the differential diagnoses.

Complete Cognitive Recovery and Survival From Massive Pulmonary Embolism During General Anesthesia after Administration of Alteplase: A Case Report

Presented herein is the case of a 37-year-old male who was scheduled for an anterior decompressive laminectomy after suffering trauma to the cervical area (C6-C7). An intraoperative acute pulmonary embolism (APE) was suspected after persistent hypoxemia and a decreased end-tidal CO2 that was refractory to proper management. After 6 intraoperative episodes of cardiac arrest that followed, intravenous alteplase (thrombolytic therapy) was administered, and the patient was stabilized without major complications. Eventually, APE was successfully diagnosed and treated. The experience served as reference for the diagnosis and management of APE under general anesthesia.

Surgery of degenerative thoracic spinal stenosis-long-term outcome with quality-of-life after posterior decompression via an uni- or bilateral approach

BACKGROUND

The rate of degenerative thoracic spinal stenosis (TSS) as underlying pathology for myelopathy is not precisely known, and larger case series are only available for the Asian region. We present one of the largest European series to evaluate rate and clinical outcome after dorsal decompression via a uni- or bilateral approach.

METHOD

We investigated patients' characteristics, imaging/surgical parameters, and outcomes with quality-of-life (QOL) in all patients who underwent surgical treatment for TSS between 2013 and 2018 in a university neurosurgical clinic.

RESULTS

From 645 patients with surgery for degenerative spondylotic myelopathy within 6 years, 28 patients (4.3%) suffered from TSS. Median age was 70.4 years with a slight predominance of the female sex (m:f = 1:1.3). The most frequent symptoms (mean duration 7.6 months) were ataxia (61%) and sensory changes (50%). The stenoses (median Naganawa score 3) mostly resulted from a combined osseous/ligamentous hypertrophy and disc prolapse, the majority located below Th8 (75%). Nineteen patients with lateralized compression underwent bilateral decompression via a unilateral approach (fenestration/hemilaminectomy with "undercutting" procedure), and 9 patients with circular pathology underwent bilateral-approached decompression (laminectomy). There were no significant differences of patients' characteristics, blood loss, operation time, and in-patient stay between both surgical groups. Independent from the mode of surgery, the spinal canal was significantly (p < 0.001) widened (median Naganawa score 0), and pain (p = 0.04), myelopathy (mJOA score p = 0.01), and QOL (Oswestry Disability Index, p = 0.03; SF-36-MCS, p = 0.01) were significantly improved at long-term follow-up (mean 35.1 months).

CONCLUSIONS

Non-tumorous myelopathy is caused in about 4% of patients by TSS and can be effectively treated by surgical decompression via both a uni- or bilateral approach.