Surgical Management of Giant Thoracic Paraspinal Schwannomas.

BACKGROUND: Giant paraspinal thoracic schwannomas (GPTSs) are benign, slow-growing, encapsulated lesions. They can be intracanalicular, span more than 2 vertebral bodies, and/or have a foraminal component with extraspinal extension >2.5 cm. They pose surgical challenges because of the often unfamiliar complex regional anatomy. We report the largest series of GPTSs and discuss regional surgical strategies for tumors in the thoracic spine. METHODS: We conducted a retrospective review of GPTSs operated at a national spinal referral center between December 2008 and October 2019. Inclusion criteria included World Health Organization grade 1 GPTS. Patient demographics, clinical features, radiology, and histopathology were assessed. RESULTS: Seventeen patients (12 females, 5 males) had a mean age of 48.1 years (range 21-65 years). Five GPTS (29%) were located at T1-T3, 6 (35%) at T4-6, and 6 (35%) below T6. The mean maximum diameter was 58.5 ± 19.1 mm (range 30-91 mm). Mean volume was 90.9 cm3 (range 19.1-350.6 cm3). Twelve (70%) had a fluorodeoxyglucose positron emission tomography scan showing low (25%) or moderate to high (75%) uptake. Six patients (35%) had preoperative computed tomography-guided biopsy. Surgical approaches included 1) manubriotomy and variations (4/17); 2) high lateral thoracotomy (4/17); 3) posterior parascapular (1/17); 4) standard lateral thoracotomy (3/16); 5) posterior/posterolateral (2/17); and 6) combined posterior and thoracotomy (3/17). All patients had gross total resection and were grade 1 cellular schwannomas. No recurrence at final follow-up (mean 36.1 months, range 8-130 months). CONCLUSIONS: A number of approaches are available to resect GPST in specific locations in the thoracic spine. Total resection is achievable despite complex regional anatomy, location, and tumor extension but often requires anterior or combined approaches.

Intramuscular Local Anesthetic Infiltration at Closure for Postoperative Analgesia in Lumbar Spine Surgery: A Systematic Review and Meta-Analysis.

STUDY DESIGN: Systematic Review and Meta-Analysis OBJECTIVE.: To identify whether intramuscular local anesthetic infiltration prior to wound closure was effective in reducing postoperative pain and facilitating early discharge following lumbar spine surgery. SUMMARY OF BACKGROUND DATA: Local anesthetic infiltration prior to wound closure may form part of the multimodal strategy for postoperative analgesia, facilitating early mobilization and discharge. Although there are a number of small studies investigating its utility, a quantitative meta-analysis of the data has never been performed. METHODS: This review was conducted according the PRISMA statement and was registered with the PROSPERO database. Only randomized controlled trials were eligible for inclusion. Key outcomes of interest included time to first analgesic demand, total postoperative opiate usage in the first 24 hours, visual analogue score (VAS) at 1, 12 and 24 hours and postoperative length of stay. RESULTS: Eleven publications fulfilled the inclusion criteria. A total of 438 patients were include; 212 in the control group and 226 in the intervention group. Local anesthetic infiltration resulted in a prolonged time to first analgesic demand (mean difference (MD) 65.88 minutes, 95% confidence interval (95% CI) 23.70 to 108.06, P.0.002) as well as a significantly reduced postoperative opiate demand (M.D. -9.71 mg, 95% CI -15.07, -4.34, p = 0.0004). There was a small but statistically significant reduction in postoperative visual analogue score (VAS) at 1 hour (M.D. -0.87 95%CI -1.55, -0.20, p = 0.01), but no significant reduction at 12 or 24 hours (p = 0.93 and 0.85 respectively). CONCLUSION: This systematic review and meta-analysis provides evidence that postoperative intramuscular local anaesthetic infiltration reduces postoperative analgesic requirements and the time to first analgesic demands for patients undergoing lumbar spine surgery. Key research priorities include optimization of the choice and strength of local anaesthetic agent and health-economic analyses to strengthen the case for routine use of postoperative local anesthetics in lumbar spine surgery. LEVEL OF EVIDENCE: 1.

Joint arthropathy at the cranio-vertebral junction. Scintigraphic patterns on bone SPECT/CT.

Osteoarthritic degeneration at the cranio-vertebral junction (CVJ) is an underrecognized source of suboccipital and neck pain, limited range of motion and cervicogenic headaches. Correlation of radiographic findings with clinical symptoms is often difficult. Limited evidence currently exists to support the use of bone single-photon emission computed tomography/computed tomography (SPECT/CT) in this subgroup of patients. The aim of this study was to describe the scintigraphic patterns of joint arthropathy at the CVJ on bone SPECT/CT in patients with suboccipital/neck pain and cervicogenic headache. Patients with more than 3 months of suboccipital/neck pain/cervicogenic headache and abnormal SPECT/CT findings at the CVJ were included. Patients with known/suspected malignancy, trauma, infectious processes and previous surgery at the CVJ were excluded. Neck disability index (NDI), visual analogue scale (VAS) and treatment were recorded for each patient. Patterns of osteoblastic activity at the CVJ on bone SPECT/CT were described and correlated with arthritic changes on conventional scans. Eighteen patients were included (10 females, mean age 68). Mean NDI score was 22. Mean VAS was 7.5. On bone SPECT/CT, it was found that 13 patients had high osteoblastic activity unilaterally at the atlanto-axial joint (AAJ); two patients at the atlanto-dental joint (ADJ), one at the occipito-atlantal joint (OAJ), one at both OAJ and ADJ and one at the level of C2 pars/pedicle unilaterally. Metabolic activity on SPECT/CT was associated with severe degenerative changes on CT scans. The ability of hybrid bone SPECT/CT to precisely localize osteoblastic activity at the CVJ may provide significant improvement in the diagnosis and treatment of patients with suboccipital/neck pain and joint arthropathy at the CVJ. Further clinical studies are needed to establish the real clinical impact of bone SPECT/CT in the treatment of patients with suboccipital neck pain.

British Association of Spine Surgeons standards of care for cauda equina syndrome.

This group of articles looks at the BASS guidelines for CES. TG and AC gave us the background on the long journey taken in publishing this, SA summarized the forum discussion on the BASS Web site, and NT gave us a medicolegal comment. The guidelines are concise, highlighting the need for prompt MRI scanning and as a consequence emergency surgery in appropriate cases. This has resource implication in terms of MRI availability and a comprehensive spinal on-call system. The question of whether operating "in the small hours" carries increased risk or whether we are using this as an excuse not to get out of bed needs to be addressed. CES discs tend to be more difficult than standard ones and probably associated with a higher complication rate. Literature on complications from night-time trauma surgery has considerably reduced out-of-hour operating in trauma. Guidelines on CES will allow the spinal community to prospectively collect data on a national registry which in time will allow us to further improve our understanding and treatment of this condition. Spinal surgery is quickly evolving into a separate specialty. These guidelines further highlight the need for a single spinal society to help set standards, educate, and revalidate our members. It is important that we all engage in this debate to get a consensus opinion to improve spinal practice across the United Kingdom.

Does source of funding and conflict of interest influence the outcome and quality of spinal research?

BACKGROUND/CONTEXT: There has been longstanding controversy surrounding the influence of funding source on the conduct and outcome of medical research. In 2011, a systematic review of the use of recombinant bone morphogenetic protein-2 revealed underreporting of unfavorable outcomes in some industry-sponsored trials. We hypothesize that Industrial funding and the presence of potential conflict of interest will be associated with low levels of evidence (LOE) and greater proportions of favorable outcomes in spinal research. PURPOSE: The aim of this study is to investigate the association between funding source and potential conflict of interest on the LOE and study outcome in the current spinal research. STUDY DESIGN/SETTING: Systematic review of all the spinal publications in five leading spinal, orthopedics, neurosurgery, and general medical journals during 2010 (print and online). Supplements were included. OUTCOME MEASURE: Outcome and the LOE of research papers. METHODS: Two reviewers independently assessed all publications. Commentaries, editorials, letters, open operating theatres, case reports, narrative reviews, and study protocols were excluded. The self-reported potential conflict of interest and type of funding was extracted from each paper. Funding type was classified as foundation, industry, public, intramural, multiple (including industry), multiple (without industry), and unfunded. The outcome of each study was classified as favorable, unfavorable, equivocal, or not applicable. Clinical publications were ranked using the LOE guidelines produced by the Oxford Center for Evidence-Based Medicine. RESULTS: Overall, 1356 papers were analyzed, out of which 864 were suitable for LOE grading. There was good interobserver reliability for assignment of LOE grade, κ=0.897 (p<.01) and study outcome κ=0.804 (p<.01). A significant association was found between LOE and source of funding (p<.01). Industry-funded studies had the greatest proportion of level IV evidence (65%). There was a significant association between the funding source and study outcome (p=.01). The proportion of industry-funded studies with favorable outcomes (88%) was higher than that of publicly and foundation-funded studies (73% and 74%, respectively). The associated odds ratio for reporting favorable outcomes in industry-funded studies compared with studies with public and foundation funding was 2.7 (95% confidence interval [CI], 1.4-5.3), and 2.6 (95% CI, 1.3-5.2), respectively. A significant association between LOE and study outcome (p<.01) was also identified. Level I studies had the highest proportions of unfavorable (14%) and equivocal (23%) outcomes. Level IV studies had the highest proportion of favorable outcome (85%). There was no association between self-reported conflict of interest and LOE (p=.83) or study outcome (p=.25). CONCLUSION: We demonstrated a significant association between source of funding, study outcome, and LOE in spinal research. A large proportion of industry funded research was shown to provide level IV evidence and report favorable outcome.

Evaluation of neck pain with (18)F-NaF PET/CT.

AIM: (18)F-Sodium fluoride ((18)F-NaF) PET/computed tomography (CT) has improved spatial resolution in the cervical spine compared with single photon emission computed tomography/CT techniques using traditional tracers. Limited data are available, however, on its effectiveness in the management of the symptomatic cervical spine, and the aim of this study was therefore to elucidate this issue. PATIENTS AND METHODS: A retrospective study was carried out between April 2011 and April 2012. Across this period, 66 patients were referred to the department for the assessment of neck pain, of whom 58 were included in the study. (18)F-NaF was used as the tracer and images were acquired on an integrated PET/CT scanner. All studies were evaluated by either consultant nuclear medicine physicians or by a radiologist. Two consultant neurosurgeons correlated the imaging reports with the clinical data from the patient notes to give an overall impression as to how beneficial the test had been with regard to patient management. RESULTS: In 49/58 (84.5%) cases, the (18)F-NaF PET/CT report was thought to have been clinically useful in patient management. In 9/58 (15.5%) cases, the report was thought not to have been clinically beneficial, generally because of high background vertebral uptake of (18)F-fluoride secondary to degenerative disease. CONCLUSION: As our experience with (18)F-NaF PET/CT broadens, we believe that it will become an increasingly important tool in the evaluation and management of the symptomatic cervical spine.

Osteosarcoma of the spine: dismal past, any hope for the future?

PURPOSE: The purpose of this study was to analyse all cases of spinal osteosarcoma (OS) treated in a regional bone tumour unit over the last 27 years. We were primarily interested in overall survival following tumour surgery, and if there is a difference in the survival of patients undergoing en bloc resection versus non-en bloc surgery. METHODS: Prospectively maintained tumour databases were searched in a regional bone tumour unit. All cases of surgically managed spinal OS were extracted and inpatient notes, imaging (including staging), histological margin status, and outcomes (neurological deficit and survival curves) were reviewed. RESULTS: Twenty-six patients were identified between 1985 and 2012. The median age was 26.5 years (range 6-78 y). Overall Kaplan-Meier survival was 69.5% (95% CI: 46.3-84.2%) and 10.8% (95% CI: 1.8-29.0%) at 1 and 5 years, respectively. There appears to be improved survival associated with primary spinal OS compared to that of metastatic disease, but this does not reach statistical significance (p = 0.29, Cox proportional hazards analysis). En bloc resection results in a significantly improved survival time compared to non-en bloc (biopsy and debulking): 44.1% alive at 2 years compared to 9.4%, respectively, p = 0.009. CONCLUSIONS: En bloc resection for primary spinal OS is associated with improved survival; there have been major changes in both surgical treatment and chemo/radiotherapy regimens over the period studied, potentially confounding the interpretation.

Intraoperative assessment of human spinal cord perfusion using near infrared spectroscopy with indocyanine green tracer technique.

BACKGROUND CONTEXT: Despite the significant interest in the assessment of human cerebral perfusion, investigations into human spinal cord perfusion (SCP) are scarce. Current intraoperative monitoring of spinal cord relies on the assessment of neural conduction as a surrogate for SCP. However, there are various inherent limitations associated with the use of these techniques. Near infrared spectroscopy (NIRS) has been successfully used for monitoring and assessment of human cerebral perfusion and has shown promising results in intraoperative assessment of SCP in animal models. PURPOSE: The aim of this study was to investigate whether it is possible to monitor physiological changes in human SCP intraoperatively using NIRS with indocyanine green (ICG) tracer technique. We used this technique to calculate the human spinal cord carbon dioxide (CO2) reactivity index. In addition, we investigated whether the lamina causes significant attenuation of NIRS signals. STUDY DESIGN/SETTING: Intraoperative human experimental study. PATIENT SAMPLE: Eighteen patients undergoing elective posterior cervical spine surgery. OUTCOME MEASURES: Carbon dioxide reactivity of human SCP. METHODS: Nine patients underwent transdural assessment of SCP, with an additional nine patients undergoing translaminar measurements. Patients' SCP was continuously monitored using an NIRO-500 NIRS monitor via a set of purpose built optodes. Their arterial ICG concentration was simultaneously assessed using a pulse dye densitometer. Patients' end-tidal CO2 was gradually increased by 7.5 mm Hg and then returned back to baseline. Three sets of measurements were taken: baseline, hypercapnic, and return to baseline. RESULTS: After hypercapnia, SCP increased by a mean of 57.2 ± 23.3% in the transdural group and 46.6 ± 36.3% in the translaminar group. Carbon dioxide reactivity index was 7.6 ± 3.2%ΔSCP/mm Hg in the transdural group and 6.4 ± 5.3 %ΔSCP/mm Hg in the translaminar group. There was no significant difference in the increase in SCP (p=.475) or the CO2 reactivity index (p=.581) observed between the transdural and the translaminar groups. CONCLUSIONS: Intraoperative NIRS with ICG tracer technique can identify an increase in the SCP in response to hypercapnia. It is possible to use this technique for monitoring SCP over the dura and the lamina. This technique could potentially be used to provide insight in to the pathophysiology and autoregulation of commonly acquired spinal cord conditions. Further research assessing the use of NIRS for monitoring of SCP is required.

Level of evidence of clinical spinal research and its correlation with journal impact factor.

BACKGROUND: Over the past two decades, there has been a growing recognition and emphasis on the practice of evidence-based medicine (EBM). The level of evidence (LOE) is used to classify clinical studies based on their quality and design. To compare the quality of scientific journals, the impact factor (IF) is the most widely used ranking measure. However, the calculation of IF is not directly dependent on the quality or LOE of clinical articles published in a journal. PURPOSE: The primary aim of this study was to evaluate the current LOE for clinical research in leading spinal journals and assess the relationship between LOE and IF. We hypothesized that most clinical research would provide level IV evidence, and that a positive correlation would exist between the proportion of high LOE articles and the journal IF. STUDY DESIGN: A systematic review of all the articles in five general spinal journals was undertaken during 2010. SAMPLE: All online articles in The Spine Journal, Spine, European Spine Journal, Journal of Neurosurgery: Spine, and Journal of Spinal Disorders and Techniques during 2010, as well as supplements were included. OUTCOME MEASURE: The LOE for each clinical study was assessed using guidelines produced by the Oxford Centre for Evidence-Based Medicine. METHODS: Two reviewers independently assessed all articles. RESULTS: Overall 703 articles were suitable for LOE grading. Of these, 4.7% provided level I evidence, 23.2% level II, 12.5% level III, and 59.6% level IV. There was a significant association between LOE and type of study (p<.001); articles on therapeutic studies had the largest proportion (71.8%) of level IV evidence. There was a strong positive correlation between the proportion of level I and II evidence and the journal impact factor (ρ=0.9; 95% confidence interval 0.1 to 0.99; p=.037). CONCLUSION: Spinal surgery journals with a higher IF contain a larger proportion of studies with high LOE, however most clinical articles provide level IV evidence of which the highest proportion are therapeutic studies. Clinicians, researchers, and journal editors should work hand in hand to enhance evidence-based practice in spinal care.

Rigid occipitocervical fixation: indications, outcomes, and complications in the modern era.

OBJECT: Over the past 40 years, various methods and instrumentation types have been developed for occipitocervical fixation (OCF) in the management of occipitocervical instability. This study reports indications, outcomes, and complications with rigid OCF using screw-rod and screw-plate instrumentation, which has comparatively less long-term data. METHODS: A prospectively maintained database identified 100 consecutive patients who underwent rigid OCF in a single unit over a period of 13 years. Patient demographics, clinical indications, pre- and postoperative radiographic findings, neck disability indices (NDIs), myelopathy disability indices (MDIs), visual analog scale (VAS) scores, and Ranawat scores were recorded. Complications including instrumentation failure were also documented. RESULTS: Underlying etiologies included rheumatoid arthritis (RA; 41%), tumor (16%), trauma (15%), congenital etiologies (14%), metabolic (6%) and inflammatory (6%) conditions, and infection (2%). The pre- and postoperative MDI and VAS scores for neck pain showed significant improvements in the RA group (MDI 64.5% vs 42.5%, p = 0.02; mean VAS 7.5 of 10 vs 3.7 of 10, p < 0.001). Improvements in MDI and NDI outcome measures were also seen in the trauma and tumor categories. Overall, there were 4 cases of instrumentation failure; all included broken rods in the stress riser region of occipitocervical rod curvature, and 1 patient also had occipital plate screw pullout. Other complications included 5 wound infections requiring wound washout, 1 vertebral artery injury (no clinical sequelae), and 1 perioperative death due to myocardial infarction. CONCLUSIONS: Rigid OCF is a safe and effective method of managing occipitocervical instability due to a variety of causes. Outcome measures are favorable, and patients with chronically debilitating diseases such as RA may benefit in terms of improvements in neurological deficit and neck pain. The complication profile is comparable to that reported in other series of OCF in the literature, as well as to the previously used semirigid type of rod/sublaminar wire fixation.

Is hybrid imaging (SPECT/CT) a useful adjunct in the management of suspected facet joints arthropathy?

PURPOSE: The purpose of this study was to assess the value of SPECT/CT imaging in patients with chronic spinal pain. METHODS: This was a retrospective consecutive study. Patients with chronic neck or back pain from outpatient spinal clinics with clinical features raising the possibility of a facetogenic pain generator and non-conclusive MRI/CT findings were included. Imaging was performed on a dual-headed, hybrid SPECT/CT γ-camera with a low-dose CT transmission scan acquired after the SPECT study. SPECT/CT studies were viewed in the coronal, axial, and sagittal planes and in 3-dimensional mode. Descriptive statistical analysis was performed. RESULTS: Seventy-two patients were included (37 females, 35 males, mean age of 53.9 years). There were 25 cervical spine scans and 49 lumbar spine scans. In the cervical spine group, 13 (52 %) patients had scintigraphically active cervical facet joint arthropathy and ten (36 %) had other pathology identified. Two thirds of patients diagnosed with facet joint arthropathy received steroid guided injections following their scans. In the lumbar spine group 34 (69.4 %) patients had scintigraphically active lumbar facet joint arthropathy and eight had other pathology identified. Twenty patients (58.8 %) diagnosed with facet joint arthropathy subsequently received steroid guided injections. CONCLUSIONS: Hybrid SPECT/CT imaging identified potential pain generators in 92 % of cervical spine scans and 86 % of lumbar spine scans. The scan precisely localised SPECT positive facet joint targets in 65 % of the referral population and a clinical decision to inject was made in 60 % of these cases.

Postoperative spinal epidural hematoma (SEH): incidence, risk factors, onset, and management.

BACKGROUND CONTEXT: Spinal epidural hematoma (SEH) is a rare, yet potentially devastating complication of spinal surgery. There is limited evidence available regarding the risk factors and timing for development of symptomatic SEH after spinal surgery. PURPOSE: To assess the incidence, risk factors, time of the onset, and effect of early evacuation of symptomatic SEH after spinal surgery. STUDY DESIGN: Multicenter case control study. PATIENT SAMPLE: All patients who underwent open spinal surgery between October 1, 1999, and September 30, 2006, at the National Hospital For Neurology and Neurosurgery (NHNN) and the Wellington Hospital (WH) were reviewed. OUTCOME MEASURES: Frankel grade. METHODS: Patients who developed SEH and underwent evacuation of the hematoma were identified. Two controls per case were selected. Each control had undergone a procedure with similar complexity, at the same section of the spine, at the same hospital, and under the same surgeon within 6 months of the initial operation. RESULTS: A total of 4,568 open spinal operations were performed at NHNN and WH. After spinal surgery, 0.22% of patients developed symptomatic SEH. Alcohol greater than 10 units a week (p=.031), previous spinal surgery (p=.007), and multilevel procedures (p=.002) were shown to be risk factors. Initial symptoms of SEH presented after a median time of 2.7 hours (interquartile range [IQR], 1.1-126.1). Patients who had evacuation surgery within 6 hours of the onset of initial symptoms improved a median of 2 (IQR, 1.0-3.0) Frankel grades, and those who had surgery more than 6 hours after the onset of symptoms improved 1.0 (IQR, 0.0-1.5) Frankel grade, p=.379. CONCLUSIONS: Symptomatic postoperative SEH is rare, occurring in 0.22% of cases. Alcohol consumption greater than 10 units a week, multilevel procedure, and previous spinal surgery were identified as risk factors for developing SEH. Spinal epidural hematoma often presents early in the postoperative period, highlighting the importance of close patient monitoring within the first 4 hours after surgery. This study suggests that earlier surgical intervention may result in greater neurological recovery.

Swelling and enhancement of the cervical spinal cord: when is a tumour not a tumour?

OBJECTIVE: To describe the management of patients with co-existing cervical spondylotic compression and enhancing intramedullary swelling of uncertain aetiology. We describe the key features, suggest a management plan and review the literature. MATERIAL AND METHODS: A short series of six cases with cervical myelopathy and radiological features of spondylotic compression, swollen cervical cord and intramedullary enhancement is described. Detailed descriptions of clinical features, radiological findings, surgical approaches and outcomes are discussed. All patients underwent cervical decompression via an anterior approach, posterior approach or both. Despite initial concerns that the aetiology might be tumour, no biopsy of cervical cord was required in any of the cases. RESULTS: Symptoms improved in four cases whilst contrast enhancement only improved in two cases following decompression. One patient who failed to improve postoperatively was found to have neurosarcoidosis. No patient became worse after the cervical decompression. CONCLUSION: Swelling of the spinal cord with enhancement and co-existing spondylotic cord compression, in the first instance, should be treated by decompression only. Biopsy to diagnose intrinsic tumour or inflammatory conditions should not be performed unless there is radiological or clinical progression despite adequate decompression.

Spontaneous resolution of discal cyst around L5 nerve root: case report and review of literature.

The treatment of discal cysts is controversial, with different surgical options described in the literature. We present an interesting case of spontaneous resolution of a symptomatic discal cyst. Based on our case report, we recommend non-operative management in the first instance and an up-to-date MRI scan before contemplating surgery.

Lumbar interspinous spacers: a systematic review of clinical and biomechanical evidence.

STUDY DESIGN: Systematic review. OBJECTIVE: To evaluate the current biomechanical and clinical evidence available on the use and effectiveness of lumbar interspinous devices and to recommend indications for their use. SUMMARY OF BACKGROUND DATA: Lumbar interspinous spacers (ISPs) have recently become popular as an alternative treatment for lumbar degenerative disease. Several spacers are currently available in the market and there have been various proposed indications. The relevant biomechanical and clinical papers are analyzed. METHODS: A systematic review of clinical and biomechanical studies was done using the following key words: interspinous implants, interspinous devices, interspinous spacers, dynamic stabilization, X-STOP, Coflex, Wallis, DIAM. The database inclusions were MEDLINE, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and PubMed. The main outcome measure was clinical outcome assessment based on validated patient-related questionnaires. Biomechanical studies were analyzed to evaluate the effects of ISPs on the kinematics of the spine. The methodology of the clinical studies was also analyzed. RESULTS: Largest number of studies has been with the X-STOP device. The biomechanical studies with all the devices showed that ISPs have a beneficial effect on the kinematics of the degenerative spine. Apart from 2 randomized controlled trials, the other studies with the X-STOP device were not of high methodologic quality. Nevertheless, analysis of these studies showed that X-STOP may improve outcome when compared to nonoperative treatment in select group of patients aged 50 or over, with radiologically confirmed lumbar canal stenosis and neurogenic claudication, who have improvement of their symptoms in flexion. Studies on the other devices show satisfactory outcome to varying degrees. However, due to small number and poor design of the studies, it is difficult to clearly define indications for their use in lumbar degenerative disease. CONCLUSION: Lumbar ISPs may have a potential beneficial effect in select group of patients with degenerative disease of the lumbar spine. However, further good quality trials are needed to clearly outline the indications for their use.

Anterior cervical corpectomy: review and comparison of results using titanium mesh cages and carbon fibre reinforced polymer cages.

Different types of cages have recently become available for reconstruction following anterior cervical corpectomy. We review the results using titanium mesh cages (TMC) and stackable CFRP (carbon fibre reinforced polymer) cages. Forty-two patients who underwent anterior cervical corpectomy between November 2001 and September 2008 were retrospectively reviewed. Pathologies included cervical spondylotic myelopathy (CSM), cervical radiculopathy, OPLL (ossified posterior longitudinal ligament), metastasis/primary bone tumour, rheumatoid arthritis and deformity correction. All patients were evaluated clinically and radiologically. Outcome was assessed on the basis of the Odom's criteria, neck disability index (NDI) and myelopathy disability index (MDI). Mean age was 60 years and mean follow-up was 1½ years. Majority of the patients had single-level corpectomy. Twenty-three patients had TMC cages while 19 patients had CFRP cages. The mean subsidence noted with TMC cage was 1.91 mm, while with the stackable CFRP cage it was 0.5 mm. This difference was statistically significant (p < 0.05). However, there was no statistically significant correlation noted between subsidence and clinical outcome (p > 0.05) or between subsidence and post-operative sagittal alignment (p > 0.05) in either of the groups. Three patients had significant subsidence (> 3 mm), one of whom was symptomatic. There were no hardware-related complications. On the basis of the Odom's criterion, 9 patients (21.4%) had an excellent outcome, 14 patients (33.3%) had a good outcome, 9 patients (21.4%) had a fair outcome and 5 patients (11.9%) had a poor outcome, i.e. symptoms and signs unchanged or exacerbated. Mean post-operative NDI was 26.27% and mean post-operative MDI was 19.31%. Fusion was noted in all 42 cases. Both TMC and stackable CFRP cages provide solid anterior column reconstruction with good outcome following anterior cervical corpectomy. However, more subsidence is noted with TMC cages though this might not significantly alter the clinical outcome unless the subsidence is significant (>3 mm).

Non-dysraphic intradural spinal cord lipoma: case series, literature review and guidelines for management.

PURPOSE: Non-dysraphic intradural spinal cord lipomas are rare lesions and the management remains controversial. We present our experience with five cases and propose guidelines for their management. METHODS: Five patients who underwent surgery for non-dysraphic spinal cord lipomas between January 2004 and April 2009 were retrospectively reviewed. All had varying degrees of neurological symptoms at the time of surgery with characteristic features on magnetic resonance imaging (MRI). All patients underwent decompression with a laminectomy/laminoplasty and debulking. The dura was primarily closed in one patient. The literature was also extensively reviewed regarding these rare lesions and optimum management guidelines proposed. RESULTS: The age at presentation ranged from 17 to 52 years (mean 32.2). Minimum follow-up was 8 months and maximum follow-up was 5 years. There was neurological improvement following surgery in all cases. Post-operative MRI scan showed evidence of significant residual tumour in all patients. CONCLUSION: The extent of surgical resection does not necessarily correlate with clinical outcome. The aim of surgery should, therefore, be adequate decompression with preservation of neural structures. Aggressive debulking should be avoided. Onset of any neurological symptoms/signs, bowel or bladder symptoms or intractable local symptoms should be an indication for surgery.

Spinal meningocele due to iatrogenic dural puncture during epidural analgesia for childbirth: 5-year history of headache with a spinal etiology.

Patients undergoing epidural injection for labor pains occasionally sustain iatrogenic inadvertent puncture of the dura with or without damage to the underlying neurological structures. This may be associated with CSF leakage, headache, neurological deficit, and infection. Rarely, the headache persists for years. To the authors' knowledge, chronic headache due to acquired spinal meningocele featuring as a duplicated dural sac, as a sequela of traumatic inadvertent dural puncture, has not been previously reported. The authors report a case of a 20-year-old woman with persistent headaches following an epidural injection. Five years later, the persistent headache was found to be due to a large acquired spinal meningocele. The operative removal of the meningocele led to resolution of headaches. This report highlights the importance of considering a spinal condition as a culprit for chronic headache and postulates a mechanism for the formation of the acquired spinal meningocele appearing as a duplicated dural sac. The authors recommend early MR imaging of the spine for any persisting headache that has a history of attempted spinal access. If an acquired spinal meningocele collection is found, exploration with a view to complete removal of the sac should be considered. To the authors' knowledge, this is the first case report depicting a rare, treatable cause of chronic spinal hypotension resulting in headaches.