Cluneal nerve release: a systematic review.

BACKGROUND: Despite the heterogeneity of chronic lower back pain aetiologies, cluneal nerve entrapment remains underdiagnosed and poorly understood with few studies discussing the efficacy of its surgical release. OBJECTIVE: The current study opts to conduct a systematic review reporting on the efficacy of cluneal nerve surgical decompression in patients with an established diagnosis who fail conservative treatment. We aimed to systematically evaluate the literature regarding the clinical outcomes, recurrence of symptoms and revision rates of surgical intervention. METHODS: A systematic review of the English language literature dating up until May 2022 was undertaken according to the PRISMA guidelines. Isolated case reports were excluded. RESULTS: Of a total of 54 articles, 4 studies met the inclusion criteria (three were level IV evidence and one level III evidence) and were analyzed. Overall, 98 patients of mean age 61 years, (range 17-86) underwent cluneal nerve release with a mean follow-up of 25.5 months (6-58 months). There was significant improvement in symptoms post operatively in the 4 studies. No systemic or local complications were encountered during the surgeries. Four articles reported on revision surgery for recurrent symptoms in 8 patients out of 98 with a rate of 8.2%. Of the reoperated patients, 7/8 had new branches released that were not addressed initially and 1 had neurectomy for an adhered pre-released branch. CONCLUSION: This systematic review demonstrated that cluneal nerve decompression has been performed in a total of 98 patients with significant clinical improvement, zero systemic and local complications and revision rates of 8.2% of the cases.

The diagnosis and management of a vertebral artery loop causing cervical radiculopathy.

BACKGROUND: Cervical radiculopathies are rarely caused by vertebral artery loop formation, which is estimated to be present in less than 3% of patients. It is uncertain what causes the loop formation: some propose an association with spondylotic changes or trauma, whilst others suggest hypertension and atherosclerosis may be responsible. CASE REPORT 1: A 35-year-old male patient presented with signs and symptoms of cervical radiculopathy that was not improved with anterior cervical discectomy and fusion surgery performed 2 years beforehand. Vertebral artery loop was discovered at the level C5/6 on the MRI. Vertebral artery transposition surgery via a lateral approach was performed at the level of the left C5/6 for symptoms of left C6 radiculopathy. Deroofing of the transverse process was performed with post-surgical complete improvement in weakness and pain. CASE REPORT 2: A 48-year-old female patient presented with a 10-year history of left shoulder pain with occasional radiation into her middle three fingers accompanied by intermittent paraesthesia and weakness. Numerous shoulder surgeries, Botox injections and suprascapular nerve blocks had not provided any significant benefit. A vertebral artery loop was identified at the level of C3/4 and C4/5 on the left with cervical MRI. Transposition surgery of these two levels provided some post-surgical improvement in pain. CONCLUSION: Vertebral artery loop formations are a rare but potential cause for cervical radiculopathy. In two cases, the loop formations were not radiographically reported on MRI, thus clinicians should be aware of this as a differential diagnosis in the management of cervical radiculopathy. The presented surgical approach may be useful in managing future cases of vertebral artery loop formation causing cervical radiculopathy resistant to conservative measures.

Degenerative Cervical Myelopathy: A 7-Letter Coding System That Supports Decision-Making for the Surgical Approach.

OBJECTIVE: To validate with a prospective study a decision-supporting coding system for the surgical approach for multilevel degenerative cervical myelopathy. METHODS: Ten cases were presented on an internet platform, including clinical and imaging data. A single-approach (G1), a choice between 2 (G2), or 3 approaches (G3) were options. Senior and junior spine surgeons analyzed 7 parameters: location and extension of the compression of the spinal cord, C-spine alignment and instability, general morbidity and bone diseases, and K-line and multilevel corpectomy. For each parameter, an anterior, posterior, or combined approach was suggested. The most frequent letter or the last letter (if C) of the resulting 7-letter code (7LC) suggested the surgical approach. Each surgeon performed 2 reads per case within 8 weeks. RESULTS: G1: Interrater reliability between junior surgeons improved from the first read (κ = 0.40) to the second (κ = 0.76, p < 0.001) but did not change between senior surgeons (κ = 0.85). The intrarater reliability was similar for junior (κ = 0.78) and senior (κ = 0.71) surgeons. G2: Junior/senior surgeons agreed completely (58%/62%), partially (24%/23%), or did not agree (18%/15%) with the 7LC choice. G3: junior/senior surgeons agreed completely (50%/50%) or partially (50%/50%) with the 7LC choice. CONCLUSION: The 7LC showed good overall reliability. Junior surgeons went through a learning curve and converged to senior surgeons in the second read. The 7LC helps less experienced surgeons to analyze, in a structured manner, the relevant clinical and imaging parameters influencing the choice of the surgical approach, rather than simply pointing out the only correct one.

How the Ends of Bones Evolve and What They Do: The Anatomical and Biomechanical Perspective.

Skeletal ossification occurs either directly within mesenchymal tissues or indirectly through a template of hyaline cartilage. Between the epiphyses and diaphyses of long bones, hyaline cartilaginous growth plates remain and constitute the progenitor cell reservoir from which the tissue develops toward the diaphysis and determines longitudinal bone size. Growth plates exhibit a characteristic architecture with columnar cell organization and different zonal morphology. The cells increase their volume toward the diaphysis, and eventually the longitudinally arranged septa of extracellular matrix mineralize. Finally, the mineralized cartilage matrix is replaced by lamellar bone. The extracellular matrix is rich in glycosaminoglycans, proteoglycans, and collagen II; at the edges of the growth plates, collagen I, III, and collagen X, especially at the mineralization front, are also present.The geometry of the growth plates is regulated by the local mechanical environment. In general, all plates orient themselves perpendicular to the resulting compressive force vector; grooves, ridges, and lateral angulations are adaptations to withstand shear forces acting on the growth plates. The final shape of the fully grown bone is determined not only by the epiphyseal growth plates but also by their apophyseal counterpart. Both structures respond in a comparable fashion to the local mechanical environment.

Realignment of Basilar Invagination by C1-C2 Joint Distraction: A Modified Approach to a Paradigm Shift.

BACKGROUND: Distraction of the C1-C2 joint and maintenance thereof by introduction of spacers into the articular cavity can successfully and durably reduce basilar invagination (BI). Thus, with the adjunct of instrumented fusion and decompression, BI-induced myelopathy can be efficiently treated with a one-stage posterior approach. This intervention is technically challenging, and in this paper we describe a procedural variation to facilitate the approach. METHODS AND RESULTS: Through a description of a case of BI, the main anatomopathological alteration underlying and perpetrating the condition of BI is elucidated. A technique of realignment of BI is then described in which this alteration is specifically targeted and neutralized. The result is a single-stage posterior-only approach with decompression, C1-C2 distraction and introduction of poly(methyl methacrylate) (PMMA) into the joint cavity. Instrumented occipitocervical fusion completes the procedure. CONCLUSION: C1-C2 joint distraction is a technically demanding procedure. By providing a modification of the original technique and a detailed description of the crucial steps necessary to successfully and safely carry it out, we hope to make this excellent procedure more approachable.

Stent augmentation of an anterior odontoid screw for type 2 odontoid fracture-dislocation in the elderly population: Report of two cases and literature review.

The fixation of type 2 odontoid fractures poses significant challenges in the elderly population due to coexistent osteoporosis and communition resulting in a high failure rate with conventional anterior screw fixation. Two elderly patients with unstable odontoid peg fractures and coexistent osteoporosis were treated with stentoplasty and anterior odontoid screw fixation. Additional anterior transarticular C1-2 screws were placed to address C1-2 instability. Both patients made an uneventful clinical recovery. One of the anterior C1-2 screws loosened due to the poor purchase in the osteoporotic bone in one patient. This did not affect the final outcome, and both the patients demonstrated maintained reduction and good alignment of odontoid peg after 2 years of follow-up. There was no intraoperative cement leak, pseudoarthrosis, or loss of reduction. Stentoplasty coupled with the anterior odontoid screw is a safe technique that can provide a biomechanically sound fixation of type 2 odontoid fractures in the presence of osteoporosis and significant communition.

Bone marrow washout for multilevel vertebroplasty in multiple myeloma spinal involvement. Technical note.

INTRODUCTION: Vertebral involvement is found in a high percentage of multiple myeloma (MM) patients, often requiring multilevel surgical treatment to reduce pain and disability and to receive prompt access to oncological care. We describe the clinical use of washout technique for multilevel vertebroplasty in MM patients with diffuse spinal involvement. The aim of this technique is to reduce the risk of pulmonary fat embolism after cement injection and possibly to increment the amount of cement and treated levels in one surgical stage. METHODS: Three patients were treated with the washout technique prior to multilevel vertebroplasty for thoracolumbar diffuse spinal involvement in multiple myeloma. We describe the surgical technique and review the pertinent literature. RESULTS: The technique is clinically safe and effective in reducing pain, without significant complications. Two six-level vertebroplasties were performed in one case, allowing a larger amount of cement injected and a prompt start of the oncological treatment. CONCLUSIONS: Multilevel vertebroplasty in MM patients with diffuse spinal involvement carries the advantages of reducing pain, avoid repeated surgeries and faster return to oncological regimen. Cardiovascular complications, including pulmonary embolism, are rare but can have fatal consequences. It is mainly due to bone marrow mobilization during cement injection and the risk increases with the amount of cement injected and the number of treated levels. Despite multilevel treatment at the same stage, we did not observe any significant complication in our series. Further studies are needed to confirm the preliminary results of this technique. These slides can be retrieved under electronic supplementary material.

Hollow modular anchorage (HMA) screws for anterior transvertebral fixation in high-grade spondylolisthesis cases requiring 360 degrees in-situ fusion.

OBJECTIVE: 360 degrees in-situ fusion for high-grade spondylolisthesis showed satisfying clinical long-term results. Combining anterior with posterior surgery increases fusion rates. Anteriorly inserted transvertebral HMA screws could be an alternative to strut graft constructs or cages, avoiding donor site complications. In addition, complete posterior muscle detachment is avoided and the injury risk of neural structures is minimized. This study investigates the use of HMA screws in this context. MATERIAL AND METHODS: Five consecutive patients requiring L4-S1 in-situ fusion for isthmic spondylolisthesis (four Grade 3 and one Grade 4) were included. The L5/S1 level was fused with an HMA screw filled with local bone and bone morphogenic protein (BMP2), inserted via the L4/5 disc space level. An L4/5 stand-alone interbody fusion with additional minimal invasive posterior screw fixation was added. RESULTS: Transvertebral insertion of the HMA device was accomplished via a retroperitoneal approach to L4/L5 in all cases without exposure of L5/S1. Blood loss ranged from 150 ml-350 ml. No intraoperative complication occurred. One patient developed posterior wound infection requiring debridement. Solid fusion was confirmed with a CT scan after 6 months in all patients. All patients improved to unrestricted activities of daily living with two being limited by occasional back pain. CONCLUSIONS: HMA screws allow for effective lumbosacral fusion via a limited anterior exposure. This is technically easier than posterior exposure of the lumbosacral junction in high-grade spondylolisthesis requiring 360 degrees fusion.

The safe use of long screws in L5/S1 stand-alone anterior interbody fusion for olisthesis cases.

BACKGROUND: Stand-alone anterior interbody fusion (STALIF) with poly-ether-ether-ketone (PEEK) cages could offer a treatment option in olisthesis cases. The fixation of the PEEK-cage at the L5/S1 inferior endplate with long divergent screws however might endanger neural sacral structures, especially the S1 nerve root. If shorter screws are used, the achieved bony purchase might not be sufficient to resist the pull out and shear forces at the lumbosacral junction. The aim of the present investigation was to evaluate the use of long screws in PEEK-cages for olisthesis cases at the L5/S1 segment and its neurological complications. MATERIAL AND METHODS: 11 Patients (6 males) with a mean age of 47(± 15.1) years between 2013-2015 designated for an STALIF at the L5/S1 level were consecutively included in the present study. All patients had a Grade 1 or 2 slippage according to Meyerding. PEEK cages (SynFix-LR®, Depuy Synthes) were implanted with 30mm screws at the baseplate of L5/S1 in all patients. Perioperative and postoperative long-term complications were evaluated. Furthermore, radiological follow-up was performed (CT-scan at 6 months, X-ray at 6, 12 and 24 months). RESULTS: 6 patients suffered from an isthmic, 1 from a degenerative olisthesis. 4 patients with iatrogenic spondylolisthesis were included. Pre-operative radiculopathy was noted in 10 patients. 9 patients with pre-operative radiculopathy showed relief of symptoms until the last follow-up after 24 months. Fusion was achieved in all patients after 6 months. No screw-displacement, breakage or violation of the neural foramen was noted. Furthermore, no implant failure or pull-out fractures were seen. CONCLUSION: In this investigation, no complication due to the use of long divergent locking screws was noted. In addition, the majority of patients showed permanent relief of radiculopathy symptoms at the 2 years follow-up. This study demonstrates the safe usage of long divergent locking screws in the baseplate of L5/S1 in anterior interbody fusion at the L5/S1 level.

Comparison of in vitro biocompatibility of silicone and polymethyl methacrylate during the curing phase of polymerization.

Adverse events have been reported with acrylic bone cements. However, current test standards for acrylic materials fail to characterize the potentially harmful monomers released during the curing stage. In clinical applications, materials are implanted into the human body during this phase. Silicone may be a safer alternative to acrylic cements. Silicone is used in medical applications for its biocompatibility and stability characteristics. Previously, no study has been completed which compares silicone to acrylic cements. In this study, both materials were injected into the cell medium during the curing process which more accurately reflects clinical use of material. Initially, cell cultures followed ASTM standard F813-07 which fails to capture the effects of monomer released during curing. Subsequently, a modified cell culture method was employed which evaluated cytotoxicity while the materials cured. The objective of this study was to capture toxicity data during curing phase. Thus, the test method employed measured and excluded the impact of the exothermic reaction temperature of polymethyl methacrylate (PMMA) on cell growth. The concentration of PMMA monomer was measured at 1 and 24 h after injecting PMMA into culture plates in a manner consistent with established cell growth methodologies. Our results indicate current in vitro cytotoxicity assays recommended by ASTM standards are unable to reveal the real cytotoxic effect caused by methyl methacrylate monomers during polymerization. Our modified experiment can more accurately illustrate the true nature of the toxicity of materials and improve assay results. In these tests, silicone based elastomeric polymers showed excellent cytocompatibility. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2693-2699, 2018.

New method for correction of lumbo-sacral kyphosis deformity in patient with high pelvic incidence.

STUDY DESIGN: Technical note. OBJECTIVE: We describe a novel technique of bilateral longitudinal sacral osteotomy allowing direct reduction of high pelvic incidence (PI) and correction of sagittal imbalance. METHODS: A 25-year-old female patient presented with a disabling lumbo-sacral kyphosis fused in situ through previous operations with residual low-grade wound infection and grade IV L5/S1 spondylolisthesis with severity index (SI) of 65%. A two-stage correction was performed. First anterior in situ fixation of the L4-L5-S1 segments was performed using a hollow modular anchorages (HMA) screw and L3/L4 anterior interbody cage. The second stage consisted of instrumentation of the lower lumbar spine and pelvis; placement of an S1 transverse K-wire as pivot point and bilateral longitudinal sacral osteotomy which allowed for gradual retroversion of the central sacrum relative to the pelvis. RESULTS: Sacrum was derotated by 30° which allowed to restore spinal sagittal balance and decrease SI by 15%. Postoperative recovery was complicated by a flare up of the pre-existing deep wound infection. CONCLUSIONS: Bilateral longitudinal sacral osteotomy appears to be a safe and efficient way of correcting the sagittal imbalance caused by an extremely high PI. Although technically demanding, it achieves good radiological and functional outcomes and avoids entering the spinal canal.

The computed tomography-based fractal analysis of trabecular bone structure may help in detecting decreased quality of bone before urgent spinal procedures.

BACKGROUND CONTEXT: To date, no reliable method is available to determine the parameters of bone density based on the routine spinal computed tomography (CT) in the emergency setup. We propose the use of fractal analysis to detect patients with poor quality of bone before urgent or semi-urgent spinal procedures. PURPOSE: This study aimed to validate the hypothesis that the CT-based fractal analysis of the trabecular bone structure may help in detecting patients with poor quality of bone before urgent spinal procedures. STUDY DESIGN: This is a retrospective analysis of prospectively collected data. METHODS: Patients in whom the dual-energy x-ray absorptiometry (DEXA) scan and lumbar spine CT were performed at an interval of no more than 3 months were randomly selected from a prospectively collected database. Diagnostic axial CT scans of L2, L3, and L4 vertebrae were processed to determine the fractal dimension (FD) of the trabecular structure of each spinal level. Box-count method and ImageJ 1.49 software were used. The FD was compared with the results of the DEXA scan: bone mineral density (BMD) and T-score by mean of correlation coefficients. Receiver operating characteristic curve analysis was later performed to determine the cutoff value of FD. RESULTS: A total of 102 vertebral levels obtained from 35 patients (mean age 60±18 years; 29 female) were analyzed. The FD was significantly higher in the group of patients with decreased bone density (DBD) (T-score<-1.0) (1.67 vs. 1.43; p<.0001) and negatively correlated with BMD (R Spearman, -0.53; p<.0001) and T-score (-0.49; p<.0001). Receiver operating characteristic curve analysis revealed that a cutoff value of FD>1.53 indicates DBD (p<.0001; area under the ROC curve [AUC], 0.84; 95% confidence interval [CI], 0.76-0.91). CONCLUSIONS: This study shows that fractal analysis of the lumbar spine CT images may be used to determine bone density before spinal instrumentation (eg, metastatic or traumatic cord compression). Further prospective studies comparing results of the fractal analysis of CT scans with quantitative CT (qCT) are warranted.

Development of a new assessment tool for cervical myelopathy using hand-tracking sensor: Part 1: validity and reliability.

PURPOSE: To assess the reliability and validity of a hand motion sensor, Leap Motion Controller (LMC), in the 15-s hand grip-and-release test, as compared against human inspection of an external digital camera recording. METHODS: Fifty healthy participants were asked to fully grip-and-release their dominant hand as rapidly as possible for two trials with a 10-min rest in-between, while wearing a non-metal wrist splint. Each test lasted for 15 s, and a digital camera was used to film the anterolateral side of the hand on the first test. Three assessors counted the frequency of grip-and-release (G-R) cycles independently and in a blinded fashion. The average mean of the three was compared with that measured by LMC using the Bland-Altman method. Test-retest reliability was examined by comparing the two 15-s tests. RESULTS: The mean number of G-R cycles recorded was: 47.8 ± 6.4 (test 1, video observer); 47.7 ± 6.5 (test 1, LMC); and 50.2 ± 6.5 (test 2, LMC). Bland-Altman indicated good agreement, with a low bias (0.15 cycles) and narrow limits of agreement. The ICC showed high inter-rater agreement and the coefficient of repeatability for the number of cycles was ±5.393, with a mean bias of 3.63. CONCLUSIONS: LMC appears to be valid and reliable in the 15-s grip-and-release test. This serves as a first step towards the development of an objective myelopathy assessment device and platform for the assessment of neuromotor hand function in general. Further assessment in a clinical setting and to gauge healthy benchmark values is warranted.

Development of a new assessment tool for cervical myelopathy using hand-tracking sensor: Part 2: normative values.

PURPOSE: To set a baseline measurement of the number of hand flexion-extension cycles and analyse the degree of motion in young healthy individuals, measured by leap motion controller (LMC), besides describing gender and dominant hand differences. METHODS: Fifty healthy participants were asked to fully grip-and-release their dominant hand as rapidly as possible for a maximum of 3 min or until subjects fatigued, while wearing a non-metal wrist splint. Participants also performed a 15-s grip-and-release test. An assessor blindly counted the frequency of grip-and-release cycles and magnitude of motion from the LMC data. RESULTS: The mean number of the 15-s G-R cycles recorded by LMC was: 47.7 ± 6.5 (test 1, LMC); and 50.2 ± 6.5 (test 2, LMC). In the 3-min test, the total number of hand flexion-extension cycles and the degree of motion decreased as the person fatigued. However, the decline in frequency preceded that of motion's magnitude. The mean frequency of cycles per 10-s interval decreased from 35.4 to 26.6 over the 3 min. Participants reached fatigue from 59.38 s; 43 participants were able to complete the 3-min test. CONCLUSIONS: Normative values of the frequency of cycles and extent of motion for young healthy individuals, aged 18-35 years, are provided. Future work is needed to establish values in a wider age range and in a clinical setting.

Intracardiac bone cement embolism as a complication of vertebroplasty: management strategy.

BACKGROUND: Vertebroplasty carries multiple complications due to the leakage of polymethylmethacrylate (PMMA) into the venous system through the iliolumbar or epidural veins. The rate of venous cement complications may vary from 1 to 10 %, with cement extravasation into the venous system in 24 % of patients. Emboli may further migrate into the right heart chambers and pulmonary arteries. Patients may vary in presentation from asymptomatic or symptoms such as syncope to life-threatening complications. CASE REPORT: We present a case of a 57-year-old lady diagnosed with osteoporosis who underwent a staged antero-posterior fixation with PMMA vertebroplasty of progressive thoraco-lumbar kyphosis caused by osteoporotic fractures to T12, L1 and L2 vertebral bodies. Four weeks after the operation, the patient developed symptoms of left-sided chest pain, tachycardia and tachypnea. CT pulmonary angiogram (CTPA) found a high-density material within the right atrium, whilst ECHO demonstrated normal systolic function. The patient was commenced on enoxaparin at therapeutic dose of 1.5 mg/kg for 3 months and remained asymptomatic. Follow-up ECHO found no change to the heart function and no blood clot on the PMMA embolus. CONCLUSIONS: Factors influencing the decision about conservative treatment included symptoms, localisation of the embolus, as well as time lapse between vertebroplasty and clinical manifestation. Patients that are commonly asymptomatic can be treated conservatively. The management of choice is anticoagulation with low-molecular-weight heparin or warfarin until the foreign body epithelialises and ceases in becoming potentially thrombogenic. Symptomatic patients with thrombi in the right atrium are commonly managed via percutaneous retrieval, whilst those with RV involvement or perforation are commonly managed with surgical retrieval. Management of individual patients should be based on individual clinical circumstances. Patients presenting with intracardiac bone cement embolism related to spinal procedures require thorough clinical assessment, cardiology input, and if required, surgical intervention.

Staged Correction of Severe Thoracic Kyphosis in Patients with Multilevel Osteoporotic Vertebral Compression Fractures.

Study Design Technical report. Objective Multilevel osteoporotic vertebral compression fractures may lead to considerable thoracic deformity and sagittal imbalance, which may necessitate surgical intervention. Correction of advanced thoracic kyphosis in patients with severe osteoporosis remains challenging, with a high rate of failure. This study describes a surgical technique of staged vertebral augmentation with osteotomies for the treatment of advanced thoracic kyphosis in patients with osteoporotic multilevel vertebral compression fractures. Methods Five patients (average age 62 ± 6 years) with multilevel osteoporotic vertebral compression fractures and severe symptomatic thoracic kyphosis underwent staged vertebral augmentation and surgical correction of their sagittal deformity. Clinical and radiographic outcomes were assessed retrospectively at a mean postoperative follow-up of 34 months. Results Patients' self-reported back pain decreased from 7.2 ± 0.8 to 3.0 ± 0.7 (0 to 10 numerical scale; p < 0.001). Patients' back-related disability decreased from 60 ± 10% to 29 ± 10% (0 to 100% Oswestry Disability Index; p < 0.001). Thoracic kyphosis was corrected from 89 ± 5 degrees to 40 ± 4 degrees (p < 0.001), and the sagittal vertical axis was corrected from 112 ± 83 mm to 38 ± 23 mm (p = 0.058). One patient had cement leakage without subsequent neurologic deficit. Decreased blood pressure was observed in another patient during the cement injection. No correction loss, hardware failure, or neurologic deficiency was seen in the other patients. Conclusion The surgical technique described here, despite its complexity, may offer a safe and effective method for the treatment of advanced thoracic kyphosis in patients with osteoporotic multilevel vertebral compression fractures.

Athletic Population with Spondylolysis: Review of Outcomes following Surgical Repair or Conservative Management.

STUDY DESIGN: Narrative review. OBJECTIVE: The study aims to critically review the outcomes associated with the surgical repair or conservative management of spondylolysis in athletes. METHODS: The English literature listed in MEDLINE/PubMed was reviewed to identify related articles using the term "spondylolysis AND athlete." The criteria for studies to be included were management of spondylolysis in athletes, English text, and no year, follow-up, or study design restrictions. The references of the retrieved articles were also evaluated. The primary outcome was time to return to sport. This search yielded 180 citations, and 25 publications were included in the review. RESULTS: Treatment methods were dichotomized as operative and nonoperative. In the nonoperative group, 390 athletes were included. A combination of bracing with physical therapy and restriction of activities was used. Conservative measures allowed athletes to return to sport in 3.7 months (weighted mean). One hundred seventy-four patients were treated surgically. The most common technique was Buck's, using a compression screw (91/174). All authors reported satisfactory outcomes. Time to return to play was 7.9 months (weighted mean). There were insufficient studies with suitably homogenous subgroups to conduct a meta-analysis. CONCLUSION: There is no gold standard approach for the management of spondylolysis in the athletic population. The existing literature suggests initial therapy should be a course of conservative management with thoracolumbosacral orthosis brace, physiotherapy, and activity modification. If conservative management fails, surgical intervention should be considered. Two-sided clinical studies are needed to determine an optimal pathway for the management of athletes with spondylolysis.

Subarachnoidal pleural fistula after resection of intradural thoracic disc herniation and multimodal treatment with noninvasive positive pressure ventilation (NPPV).

Subarachnoid pleural fistula (SPF) is a type of cerebrospinal fluid (CSF) fistula that can arise as a complication following transthoracic resection of intervertebral disc herniation in the thoracic spine. It is an abnormal communication between the subarachnoid and pleural space. Negative intrapleural pressure promotes CSF leak due to a suction effect into the pleural cavity, with little chance of spontaneous closure. Due to the risk of severe complications with CSF leak into the thoracic cavity, early diagnosis and treatment are mandatory. However, management can be challenging. We report a case of a 72-year-old woman who underwent anterior thoracic surgery to treat thoracic myelopathy caused by an ossified intradural disc herniation. The postoperative period was complicated by a subarachnoidal pleural fistula. We describe our successful treatment of this using noninvasive positive pressure ventilation and lumbar CSF drainage and review other methods reported in the literature.