Early Versus Delayed Microdiscectomy for Chronic Sciatica Lasting 4-12 Months Secondary to Lumbar Disc Herniation: A Secondary Analysis of a Randomized Controlled Trial.

OBJECTIVES: To compare the effect of delaying surgery on clinical outcome in patients with chronic sciatica secondary to lumbar disc herniation. METHODS: Patients with sciatica lasting 4-12 months and lumbar disc herniation at the L4-L5 or L5-S1 level were randomized to undergo microdiscectomy (early surgery) or to receive 6 months of nonoperative treatment followed by surgery if needed (delayed surgery). Outcomes were leg pain, Oswestry Disability Index score (ODI), back pain, SF-36 physical component (PCS) and mental component (MCS) summary scores, employment, and satisfaction measured preoperatively and at 6 weeks, 3 months, 6 months, and 1 year after surgery. RESULTS: Of the 64 patients in the early surgery group, 56 underwent microdiscectomy an average of 3 ± 2 weeks after enrollment. Of the 64 patients randomized to nonoperative care, 22 patients underwent delayed surgery an average of 53 ± 24 weeks after enrollment. The early surgery group experienced less leg pain than the delayed surgery group, which was the primary outcome, at 6 months after surgery (early surgery 2.8 ± .4 vs delayed surgery 4.8 ± .7; difference, 2.0; 95% confidence interval, .5-3.5). The overall estimated mean difference between groups significantly favored early surgery for leg pain, ODI, SF36-PCS, and back pain. The adverse event rate was similar between groups. CONCLUSIONS: Patients presenting with chronic sciatica treated with delayed surgery after prolonging standardized non-operative care have inferior outcomes compared to those that undergo expedited surgery.

Microdiscectomy Is More Cost-effective Than a 6-Month Nonsurgical Care Regimen for Chronic Radiculopathy.

BACKGROUND: A recent randomized controlled trial (RCT), performed by the authors, comparing early surgical microdiscectomy with 6 months of nonoperative care for chronic lumbar radiculopathy showed that early surgery resulted in improved outcomes. However, estimates of the incremental cost-utility ratio (ICUR), which is often expressed as the cost of gaining one quality-adjusted life year (QALY), of microdiscectomy versus nonsurgical management have varied. Radiculopathy lasting more than 4 months is less likely to improve without surgical intervention and may have a more favorable ICUR than previously reported for acute radiculopathy. QUESTION/PURPOSE: In the setting of chronic radiculopathy caused by lumbar disc herniation, defined as symptoms and/or signs of 4 to 12 months duration, is surgical management more cost-effective than 6 months of nonoperative care from the third-party payer perspective based on a willingness to pay of less than CAD 50,000/QALY? METHODS: A decision analysis model served as the vehicle for the cost-utility analysis. A decision tree was parameterized using data from our single-center RCT that was augmented with institutional microcost data from the Ontario Case Costing Initiative. Bottom-up case costing methodology generates more accurate cost estimates, although institutional costs are known to vary. There were no major surgical cost drivers such as implants or bone graft substitutes, and therefore, the jurisdictional variance would be minimal for tertiary care centers. QALYs derived from the EuroQoL-5D were the health outcome and were derived exclusively from the RCT data, given the paucity of studies evaluating the surgical treatment of lumbar radiculopathy lasting 4 to 12 months. Cost-effectiveness was assessed using the ICUR and a threshold of willingness to pay CAD 50,000 (USD 41,220) per QALY in the base case. Sensitivity analyses were performed to account for the uncertainties within the estimate of cost utility, using both a probabilistic sensitivity analysis and two one-way sensitivity analyses with varying crossover rates after the 6-month nonsurgical treatment had concluded. RESULTS: Early surgical treatment of patients with chronic lumbar radiculopathy (defined as symptoms of 4 to 12 months duration) was cost-effective, in that the cost of one QALY was lower than the CAD 50,000 threshold (note: the purchasing power parity conversion factor between the Canadian dollar (CAD) and the US dollar (USD) for 2019 was 1 USD = 1.213 CAD; therefore, our threshold was USD 41,220). Patients in the early surgical treatment group had higher expected costs (CAD 4118 [95% CI 3429 to 4867]) than those with nonsurgical treatment (CAD 2377 [95% CI 1622 to 3518]), but they had better expected health outcomes (1.48 QALYs [95% CI 1.39 to 1.57] versus 1.30 [95% CI 1.22 to 1.37]). The ICUR was CAD 5822 per QALY gained (95% CI 3029 to 30,461). The 2-year probabilistic sensitivity analysis demonstrated that the likelihood that early surgical treatment was cost-effective was 0.99 at the willingness-to-pay threshold, as did the one-way sensitivity analyses. CONCLUSION: Early surgery is cost-effective compared with nonoperative care in patients who have had chronic sciatica for 4 to 12 months. Decision-makers should ensure adequate funding to allow timely access to surgical care given that it is highly likely that early surgical intervention is potentially cost-effective in single-payer systems. Future work should focus on both the clinical effectiveness of the treatment of chronic radiculopathy and the costs of these treatments from a societal perspective to account for occupational absences and lost patient productivity. Parallel cost-utility analyses are critical so that appropriate decisions about resource allocation can be made. LEVEL OF EVIDENCE: Level III, economic and decision analysis.

Discectomy Compared with Standardized Nonoperative Care for Chronic Sciatica Due to a Lumbar Disc Herniation: A Secondary Analysis of a Randomized Controlled Trial with 2-Year Follow-up.

BACKGROUND: Randomized controlled trials evaluating acute sciatica have not demonstrated prolonged improvements in terms of patient-reported pain and function. For chronic sciatica, however, microdiscectomy has been found to be superior at 1 year. Whether this effect persists during the second year is not known. The purpose of the present study was to report the 2-year outcomes following lumbar microdiscectomy as compared with standardized nonoperative care for the treatment of chronic sciatica resulting from a lumbar disc herniation. METHODS: The present study is a secondary analysis of a previously reported randomized controlled trial with extension to 2 years of follow-up. Patients with radiculopathy for 4 to 12 months resulting from an L4-L5 or L5-S1 disc herniation were randomized to microdiscectomy or 6 months of nonoperative care followed by surgery if needed. Intention-to-treat analysis was performed at 2 years for the primary outcome (the intensity of leg pain) (range of possible scores, 0 [no pain] to 10 [worst pain]) as well as for secondary outcomes (including the Oswestry Disability Index score, the intensity of back pain, and quality of life). RESULTS: One hundred and twenty-eight patients were randomized in the present study. Twenty-four (38%) of the 64 patients who had been randomized to nonoperative care crossed over to surgical treatment by 2 years following enrollment. At the 2-year time point, the follow-up rate was approximately 70%. At 2 years, the operative group had less leg pain than the nonoperative group (mean, 2.8 ± 0.4 compared with 4.2 ± 0.4; treatment effect, 1.3 [95% confidence interval, 0.3 to 2.4]). The treatment effect favored surgery for all secondary outcome measures at 6 months and 1 year and for back pain intensity and physical function at 2 years. CONCLUSIONS: At 2 years, the present study showed that microdiscectomy was superior to nonoperative care for the treatment of chronic sciatica resulting from an L4-L5 or L5-S1 disc herniation. However, the difference between the groups did not surpass the minimal clinically important difference at 2 years as was reached at earlier follow-up points, likely as the result of patients crossing over from nonoperative to operative treatment. LEVEL OF EVIDENCE: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Surgery versus Conservative Care for Persistent Sciatica Lasting 4 to 12 Months.

BACKGROUND: The treatment of chronic sciatica caused by herniation of a lumbar disk has not been well studied in comparison with acute disk herniation. Data are needed on whether diskectomy or a conservative approach is better for sciatica that has persisted for several months. METHODS: In a single-center trial, we randomly assigned patients with sciatica that had lasted for 4 to 12 months and lumbar disk herniation at the L4-L5 or L5-S1 level in a 1:1 ratio to undergo microdiskectomy or to receive 6 months of standardized nonoperative care followed by surgery if needed. Surgery was performed by spine surgeons who used conventional microdiskectomy techniques. The primary outcome was the intensity of leg pain on a visual analogue scale (ranging from 0 to 10, with higher scores indicating more severe pain) at 6 months after enrollment. Secondary outcomes were the score on the Oswestry Disability Index, back and leg pain, and quality-of-life scores at 6 weeks, 3 months, 6 months, and 1 year. RESULTS: From 2010 through 2016, a total of 790 patients were screened; of those patients, 128 were enrolled, with 64 in each group. Among the patients assigned to undergo surgery, the median time from randomization to surgery was 3.1 weeks; of the 64 patients in the nonsurgical group, 22 (34%) crossed over to undergo surgery at a median of 11 months after enrollment. At baseline, the mean score for leg-pain intensity was 7.7 in the surgical group and 8.0 in the nonsurgical group. The primary outcome of the leg-pain intensity score at 6 months was 2.8 in the surgical group and 5.2 in the nonsurgical group (adjusted mean difference, 2.4; 95% confidence interval, 1.4 to 3.4; P<0.001). Secondary outcomes including the score on the Owestry Disability Index and pain at 12 months were in the same direction as the primary outcome. Nine patients had adverse events associated with surgery, and one patient underwent repeat surgery for recurrent disk herniation. CONCLUSIONS: In this single-center trial involving patients with sciatica lasting more than 4 months and caused by lumbar disk herniation, microdiskectomy was superior to nonsurgical care with respect to pain intensity at 6 months of follow-up. (Funded by Physicians' Services Incorporated Foundation; ClinicalTrials.gov number, NCT01335646.).

Posterolateral Versus Posterior Interbody Fusion in Lumbar Degenerative Spondylolisthesis.

STUDY DESIGN: This was a retrospective study of 2 different fusion techniques for the treatment of lumbar degenerative spondylolisthesis. OBJECTIVE: To determine whether posterior lumbar interbody fusion (IF) is associated with improved patient-rated satisfaction and functional outcome when compared with posterolateral fusion (PLF). SUMMARY OF BACKGROUND DATA: IF and PLF are widely used surgical approaches in the treatment of spondylolisthesis. Numerous studies have compared IF and PLF techniques, but inconsistent results, heterogeneous cohorts, and conflicting scientific evidence have made it difficult to reach a consensus on the optimal fusion technique. MATERIALS AND METHODS: A consecutive cohort of 87 patients who had single-level degenerative spondylolisthesis and either PLF or IF were identified from a prospectively maintained database. Short Form-36 physical and mental component score, Oswestry Disability Index, back and leg pain, and complication rate were assessed to 24 months postoperatively. Patient characteristics, clinical outcome, and complications were compared between groups. RESULTS: Of the 87 patients identified, 29 patients (33%) had PLF and 58 patients (67%) had IF. Patient follow-up was ≥85%. Foraminal stenosis (PLF, 13.8% vs. IF, 34.5%; P=0.046) was more common among the participants in the IF group. Intraoperative and postoperative complications were not different between groups (P>0.05). The reoperation rate was 3.4% in the PLF group and 10.3% in the IF group (P=0.416). Patients in the PLF group experienced similar gains in improvement in all outcome measures as those in the IF group (P>0.05). Four patients in the IF group and 3 in the PLF group were lacking evidence of radiographic fusion. These patients did have increased moderate back pain compared with patients demonstrating radiographic fusion but did not differ in any other postoperative outcomes measures. CONCLUSIONS: Type of fusion, IF or PLF, does not affect patient outcome or postoperative complication rates. LEVEL OF EVIDENCE: Level IV.

Quality of Life and Slip Progression in Degenerative Spondylolisthesis Treated Nonoperatively.

STUDY DESIGN: A prospective cohort study of consecutive patients. OBJECTIVE: Determination of the quality of life (QoL) and prevalence of slip progression in patients with degenerative lumbar spondylolisthesis managed nonoperatively. SUMMARY OF BACKGROUND DATA: Lumbar spinal stenosis secondary to degenerative lumbar spondylolisthesis is a common radiographic diagnosis associated with chronic back pain and radicular symptoms. There is limited evidence as to the clinical course in terms of validated QoL measures, and the extent of slip progression in patients with this condition treated nonoperatively. METHODS: Validated disease-specific and generic QoL metrics including SF12 physical and mental scores [SF12-physical component summary (PCS) and SF12-mental component summary (MCS)], Oswestry Disability Index (ODI), and numeric scales for back and leg pain as well as radiographic assessment of slip extent were evaluated at initial consultation (baseline) and at a minimum of 5 years after the baseline assessment. Slip progression was defined by a >5% increase in slip percentage. RESULTS: Thirty-nine of 160 (24.4%) patients elected to switch to operative management, despite no slip progression on preoperative radiographs. Seventy spondylolisthetic levels in 66 participants were assessed after a minimum of 5 years of nonoperative management. Twenty-one participants (31.8%) had slip progression. SF12-PCS, ODI, and leg pain improved similarly in both groups (P < 0.05). SF12-MCS did not change significantly in either group. Back pain improved only in the nonprogressing group. CONCLUSION: The majority of cases of low-grade spondylolisthesis do not progress over 5 years with nonoperative management. Regardless of whether there was progression or not, the mean PCS, ODI, and leg pain improved from baseline, although symptoms remained and a significant number elected to switch to surgical management before 5 years. Back pain improved with nonoperative treatment only in those without progression. LEVEL OF EVIDENCE: 2.

Treatment of thoracolumbar burst fractures: extended follow-up of a randomized clinical trial comparing orthosis versus no orthosis.

OBJECTIVE A multicenter, prospective, randomized equivalence trial comparing a thoracolumbosacral orthosis (TLSO) to no orthosis (NO) in the treatment of acute AO Type A3 thoracolumbar burst fractures was recently conducted and demonstrated that the two treatments following an otherwise similar management protocol are equivalent at 3 months postinjury. The purpose of the present study was to determine whether there was a difference in long-term clinical and radiographic outcomes between the patients treated with and those treated without a TLSO. Here, the authors present the 5- to 10-year outcomes (mean follow-up 7.9 ± 1.1 years) of the patients at a single site from the original multicenter trial. METHODS Between July 2002 and January 2009, a total of 96 subjects were enrolled in the primary trial and randomized to two groups: TLSO or NO. Subjects were enrolled if they had an AO Type A3 burst fracture between T-10 and L-3 within the previous 72 hours, kyphotic deformity < 35°, no neurological deficit, and an age of 16-60 years old. The present study represents a subset of those patients: 16 in the TLSO group and 20 in the NO group. The primary outcome measure was the Roland Morris Disability Questionnaire (RMDQ) score at the last 5- to 10-year follow-up. Secondary outcome measures included kyphosis, satisfaction, the Numeric Rating Scale for back pain, and the 12-Item Short-Form Health Survey (SF-12) Mental and Physical Component Summary (MCS and PCS) scores. In the original study, outcome measures were administered at admission and 2 and 6 weeks, 3 and 6 months, and 1 and 2 years after injury; in the present extended follow-up study, the outcome measures were administered 5-10 years postinjury. Treatment comparison between patients in the TLSO group and those in the NO group was performed at the latest available follow-up, and the time-weighted average treatment effect was determined using a mixed-effects model of longitudinal regression for repeated measures averaged over all time periods. Missing data were assumed to be missing at random and were replaced with a set of plausible values derived using a multiple imputation procedure. RESULTS The RMDQ score at 5-10 years postinjury was 3.6 ± 0.9 (mean ± SE) for the TLSO group and 4.8 ± 1.5 for the NO group (p = 0.486, 95% CI -2.3 to 4.8). Average kyphosis was 18.3° ± 2.2° for the TLSO group and 18.6° ± 3.8° for the NO group (p = 0.934, 95% CI -7.8 to 8.5). No differences were found between the NO and TLSO groups with time-weighted average treatment effects for RMDQ 1.9 (95% CI -1.5 to 5.2), for PCS -2.5 (95% CI -7.9 to 3.0), for MCS -1.2 (95% CI -6.7 to 4.2) and for average pain 0.9 (95% CI -0.5 to 2.2). CONCLUSIONS Compared with patients treated with a TLSO, patients treated using early mobilization without orthosis maintain similar pain relief and improvement in function for 5-10 years.

Influence of postoperative sagittal balance and spinopelvic parameters on the outcome of patients surgically treated for degenerative lumbar spondylolisthesis.

OBJECTIVE The object of this study was to determine the association between postoperative sagittal spinopelvic alignment and patient-rated outcome measures following decompression and fusion for lumbar degenerative spondylolisthesis. METHODS The authors identified a consecutive series of patients who had undergone surgery for lumbar degenerative spondylolisthesis between 2008 and 2012, with an average follow-up of 3 years (range 1-6 years). Surgery was performed to address the clinical symptoms of spinal stenosis, not global sagittal alignment. Sagittal alignment was only assessed postoperatively. Patients were divided into 2 groups based on a postoperative sagittal vertical axis (SVA) < 50 mm (well aligned) or ≥ 50 mm (poorly aligned). Baseline demographic, procedure, and outcome measures were compared between the groups. Postoperative outcome measures and postoperative spinopelvic parameters were compared between groups using analysis of covariance. RESULTS Of the 84 patients included in this study, 46.4% had an SVA < 50 mm. Multiple levels of spondylolisthesis (p = 0.044), spondylolisthesis at the L3-4 level (p = 0.046), and multiple levels treated with fusion (p = 0.028) were more common among patients in the group with an SVA ≥ 50 mm. Patients with an SVA ≥ 50 mm had a worse SF-36 physical component summary (PCS) score (p = 0.018), a worse Oswestry Disability Index (ODI; p = 0.043), and more back pain (p = 0.039) than those with an SVA < 50 mm after controlling for multiple levels of spondylolisthesis and multilevel fusion. The spinopelvic parameters differing between the < 50-mm and ≥ 50-mm groups included lumbar lordosis (LL; 56.4° ± 4.7° vs 49.8° ± 4.3°, respectively, p = 0.040) and LL < pelvic incidence ± 9° (51% vs 23.1%, respectively, p = 0.013) after controlling for type of surgical procedure. CONCLUSIONS Data in this study revealed that patient-rated outcome is influenced by the overall postoperative sagittal balance as defined by the SVA.

Does the wait for lumbar degenerative spinal stenosis surgery have a detrimental effect on patient outcomes? A prospective observational study.

BACKGROUND: Waits for elective spine surgery are common in Canada. We examined whether a prolonged wait for surgery for lumbar degenerative spinal stenosis was detrimental to outcome. METHODS: In this prospective observational study, we enrolled 166 consecutive patients referred to our centre for treatment of lumbar degenerative spinal stenosis between 2006 and 2010. Outcome measures were assessed at referral, preoperatively and until 24 months postoperatively. Primary outcome measures were the physical and mental component summary scores of the 36-Item Short-Form Health Survey and the Oswestry Disability Index. Secondary outcome measures included the symptom severity scale of the Zurich Claudication Questionnaire, a numeric rating scale for back and leg pain, and patient satisfaction with treatment. Wait time was defined as the time from referral to surgery. RESULTS: The follow-up rate at 2 years was 85%. The median wait time was 349 days. All health-related quality of life measures deteriorated during the waiting period, but there was no significant correlation between wait time and magnitude of the change in outcome measure. At 6 months postoperatively, the Pearson correlation was significantly positive between wait time and change in disability (r = 0.223), Zurich Claudication Questionnaire score (r = 0.2) and leg pain score (r = 0.221). At 12 months, the correlation remained significant for change in disability (r = 0.205) and was significant for change in mental well-being (r = -0.224). At 12 months, patients with a shorter wait (≤ 12 months) showed greater improvement in mental well-being (mean difference in change [and 95% confidence interval (CI)] 5.7 [1.4-9.9]) and decrease in disability (-9.3 [95% CI -15.1 to -3.6]) and leg pain (-1.6 [95% CI -3.0 to -0.3]). There were no statistically significant differences in outcome or patient satisfaction with treatment between those with shorter and longer waits at 24 months. INTERPRETATION: Patients awaiting spinal surgery experienced deterioration in health-related quality of life irrespective of the length of wait time. However, longer waits were associated with a delay in recovery during the first year after surgery.

Orthosis versus no orthosis for the treatment of thoracolumbar burst fractures without neurologic injury: a multicenter prospective randomized equivalence trial.

BACKGROUND CONTEXT: Thoracolumbar burst fractures have good outcomes when treated with early ambulation and orthosis (TLSO). If equally good outcomes could be achieved with early ambulation and no brace, resource utilization would be decreased, especially in developing countries where prolonged bed rest is the default option because bracing is not available or affordable. PURPOSE: To determine whether TLSO is equivalent to no orthosis (NO) in the treatment of acute AO Type A3 thoracolumbar burst fractures with respect to their functional outcome at 3 months. STUDY DESIGN: A multicentre, randomized, nonblinded equivalence trial involving three Canadian tertiary spine centers. Enrollment began in 2002 and 2-year follow-up was completed in 2011. PATIENT SAMPLE: Inclusion criteria included AO-A3 burst fractures between T11 and L3, skeletally mature and older than 60 years, 72 hours from their injury, kyphotic deformity lower than 35°, no neurologic deficit. One hundred ten patients were assessed for eligibility for the study; 14 patients were not recruited because they resided outside the country (3), refused participation (8), or were not consented before independent ambulation (3). OUTCOME MEASURES: Roland Morris Disability Questionnaire score (RMDQ) assessed at 3 months postinjury. The equivalence margin was set at δ=5 points. METHODS: The NO group was encouraged to ambulate immediately with bending restrictions for 8 weeks. The TLSO group ambulated when the brace was available and weaned from the brace after 8 to 10 weeks. The following competitive grants supported this work: VHHSC Interdisciplinary Research Grant, Zimmer/University of British Columbia Research Fund, and Hip Hip Hooray Research Grant. Aspen Medical provided the TLSOs used in this study. The authors have no financial or personal relationships that could inappropriately influence this work. RESULTS: Forty-seven patients were enrolled into the TLSO group and 49 patients into the NO group. Forty-six participants per group were available for the primary outcome. The RMDQ score at 3 months postinjury was 6.8 ± 5.4 (standard deviation [SD]) for the TLSO group and 7.7 ± 6.0 (SD) in the NO group. The 95% confidence interval (-1.5 to 3.2) was within the predetermined margin of equivalence. Six patients required surgical stabilization, five of them before initial discharge. CONCLUSIONS: Treating these fractures using early ambulation without a brace avoids the cost and patient deconditioning associated with a brace and complications and costs associated with long-term bed rest if a TLSO or body cast is not available.

rhBMP-2 for posterolateral instrumented lumbar fusion: a multicenter prospective randomized controlled trial.

STUDY DESIGN: Multicenter randomized controlled trial. OBJECTIVE: To evaluate the effect of recombinant human bone morphogenetic protein (rhBMP-2) on radiographical fusion rate and clinical outcome for surgical lumbar arthrodesis compared with iliac crest autograft. SUMMARY OF BACKGROUND DATA: In many types of spinal surgery, radiographical fusion is a primary outcome equally important to clinical improvement, ensuring long-term stability and axial support. Biologic induction of bone growth has become a commonly used adjunct in obtaining this objective. We undertook this study to objectify the efficacy of rhBMP-2 compared with traditional iliac crest autograft in instrumented posterolateral lumbar fusion. METHODS: Patients undergoing 1- or 2-level instrumented posterolateral lumbar fusion were randomized to receive either autograft or rhBMP-2 for their fusion construct. Clinical and radiographical outcome measures were followed for 2 to 4 years postoperatively. RESULTS: One hundred ninety seven patients were successfully randomized among the 8 participating institutions. Adverse events attributable to the study drug were not significantly different compared with controls. However, the control group experienced significantly more graft-site complications as might be expected. 36-Item Short Form Health Survey, Oswestry Disability Index, and leg/back pain scores were comparable between the 2 groups. After 4 years of follow-up, radiographical fusion rates remained significantly higher in patients treated with rhBMP-2 (94%) than those who received autograft (69%) (P = 0.007). CONCLUSION: The use of rhBMP-2 for instrumented posterolateral lumbar surgery significantly improves the chances of radiographical fusion compared with the use of autograft. However, there is no associated improvement in clinical outcome within a 4-year follow-up period. These results suggest that use of rhBMP-2 should be considered in cases where lumbar arthrodesis is of primary concern.

The reliability of differentiating neurogenic claudication from vascular claudication based on symptomatic presentation.

BACKGROUND: Intermittent claudication can be neurogenic or vascular. Physicians use a profile based on symptom attributes to differentiate the 2 types of claudication, and this guides their investigations for diagnosis of the underlying pathology. We evaluated the validity of these symptom attributes in differentiating neurogenic from vascular claudication. METHODS: Patients with a diagnosis of lumbar spinal stenosis (LSS) or peripheral vascular disease (PVD) who reported claudication answered 14 questions characterizing their symptoms. We determined the sensitivity, specificity and positive and negative likelihood ratios (PLR and NLR) for neurogenic and vascular claudication for each symptom attribute. RESULTS: We studied 53 patients. The most sensitive symptom attribute to rule out LSS was the absence of "triggering of pain with standing alone" (sensitivity 0.97, NLR 0.050). Pain alleviators and symptom location data showed a weak clinical significance for LSS and PVD. Constellation of symptoms yielded the strongest associations: patients with a positive shopping cart sign whose symptoms were located above the knees, triggered with standing alone and relieved with sitting had a strong likelihood of neurogenic claudication (PLR 13). Patients with symptoms in the calf that were relieved with standing alone had a strong likelihood of vascular claudication (PLR 20.0). CONCLUSION: The classic symptom attributes used to differentiate neurogenic from vascular claudication are at best weakly valid independently. However, certain constellation of symptoms are much more indicative of etiology. These results can guide general practitioners in their evaluation of and investigation for claudication.

CONTEXTE: La claudication intermittente peut avoir une étiologie neurogène ou vasculaire. Les médecins utilisent un profil fondé sur les particularités des symptômes pour distinguer l'une de l'autre et ceci oriente leur choix des méthodes de diagnostic de la pathologie sous-jacente. Nous avons évalué la validité de ces particularités des symptômes utilisées pour distinguer la claudication d'origine neurogène de la claudication d'origine vasculaire. MÉTHODES: Des patients atteints d'une sténose spinale lombaire (SSL) ou d'une maladie vasculaire périphérique (MVP) avérées qui se plaignaient de claudication ont réponduà 14 questions afin de caractériser leurs symptômes. Nous avons déterminé la sensibilité, la spécificité et les rapports de probabilité positifs et négatifs (RPP et RPN) à l'égard de la claudication neurogène ou vasculaire pour chacune des particularités des symptômes. RÉSULTATS: Notre étude a regroupé 53 patients. La particularité des symptômes dotée de la sensibilité la plus élevée pour ce qui est d'écarter le diagnostic de SSL a été l'absence de « déclenchement de la douleur à la simple station debout ¼ (sensibilité 0,97; RPN 0,050). Les données sur ce qui soulageait la douleur et sur la localisation des symptômes ont eu une faible portée clinique en ce qui a trait à la SSL et à la MVP. La présence d'une constellation de symptômes a donné lieu aux associations les plus solides : les patients qui manifestaient un signe du « panier d'épicerie ¼ positif et dont les symptômes étaient localisés au-dessus du genou, déclenchés par la station debout seule et soulagés en position assise présentaient une forte probabilité de claudication d'origine neurogène (RPP 13). Chez les patients dont les symptômes étaient localisés au mollet et qui étaient soulagés par la station debout, on notait une forte probabilité de claudication d'origine vasculaire (RPP 20,0). CONCLUSION: Considérés individuellement, les attributs classiques des symptômes utilisés pour distinguer la claudication d'origine neurogène de la claudication d'origine vasculaire sont au mieux faiblement valides. Toutefois, certaines constellations de symptômes éclairent bien davantage l'étiologie. Ces résultats peuvent guider l'omnipraticien dans son examen et dans son diagnostic de la claudication.

A rare case of atlantooccipital dissociation in the context of occipitalization of the atlas, with a 2-year follow-up: case report.

Atlantooccipital dislocation (AOD) is a rare and often fatal injury. In cases of survival, residual deficits are severe and often include cranial nerve palsy, quadriplegia, or respiratory issues. Occipitalization is defined as partial or complete congenital fusion of the occiput to the atlas and is exceptionally rare. The authors present a rare case of AOD superimposed on a congenital occipitalization of the atlas. This 39-year-old man had AOD following a motor vehicle collision. On examination, his overall motor score on the American Spinal Injury Association scale was 5/100, and his rectal tone was absent. Computed tomography demonstrated AOD in an area of occipitalization. Magnetic resonance imaging revealed ligamentous injury leading to C1-2 instability. Intervention included occipital cervical instrumentation fusion from the occiput to C-3. Six months postoperatively, imaging revealed fusion of the graft and consolidation of the fractured occipitalization. At the 2-year follow-up, the patient's strength was 3/5 for wrist extension and handgrip on the right side and full strength in the rest of the myotomes. Bladder and bowel function was also normalized. A high-velocity collision led to disruption of the atlantooccipital ligaments and fracture of the occipitalized lateral masses in this patient. Internal fixation and fusion led to good fusion postoperatively. Occipitalization probably led to abnormal joint mechanics at the C1-occiput junction, which might have altered the amount of force required to fracture the occipitalization and produce AOD. This difference may partially account for the favorable neurological outcome in the featured patient compared with traditional cases of AOD.

A biomechanical assessment of soft-tissue damage in the cervical spine following a unilateral facet injury.

BACKGROUND: Unilateral cervical spine facet injuries encompass a wide spectrum, including subluxations, dislocations, and fractures, and the instability produced varies greatly. The extent of anatomical disruption secondary to a unilateral facet injury is poorly understood, and few biomechanical studies have quantified the associated kinematics. The purpose of this study was to develop an experimental method that reliably produces an impending unilateral facet dislocation (perched facet) in cadaveric cervical spines and to identify the soft-tissue damage and resulting changes in cervical spine range of motion and neutral zone associated with this injury. METHODS: Nine fresh-frozen cadaveric human spinal motion segments (C4-C5 or C6-C7) were mounted in a spinal loading simulator to induce a perched unilateral facet injury based on a previously described mechanism of flexion and bending with increasing rotation. Loads were applied to simulate and measure flexion-extension, lateral bending, and axial rotation motions before and after achieving a perched facet. Preinjury and postinjury range of motion and neutral zone were analyzed with use of paired t tests for each movement. Systematic qualitative inspection and gross dissection were then performed to define the soft-tissue injury pattern. RESULTS: Range of motion and neutral zone increased following the reduction of this injury; the largest increase (294%) occurred in contralateral axial rotation (i.e., right axial rotation after a perched left facet). Postinjury dissections revealed bilateral capsular tears, 50% disc disruption, and 50% tearing of the ligamentum flavum in most specimens. The interspinous and supraspinous ligaments were stretched in less than half of the specimens and were never completely disrupted. The longitudinal ligaments were occasionally torn as extensions of anulus fibrosus disruptions. CONCLUSIONS: This study indicates that the anulus fibrosus, nucleus pulposus, and ligamentum flavum are important cervical spine stabilizers. Facet capsules were often torn bilaterally, implying a more advanced injury than a unilateral facet injury. These discoligamentous injuries result in increases in range of motion and neutral zone. CLINICAL RELEVANCE: The results from this work provide further insight into the expected injury and associated instability present in a traumatic unilateral facet injury in the cervical spine.

The importance of the posterior osteoligamentous complex to subaxial cervical spine stability in relation to a unilateral facet injury.

BACKGROUND CONTEXT: Unilateral facet disruptions are relatively common in the cervical spine; however, the spectrum of injury is large, and little is known regarding the magnitude of instability expected to be present in an isolated posterior osteoligamentous injury. PURPOSE: To quantify the contribution of the posterior osteoligamentous structures to cervical spine stability during simulated flexion-extension (FE), lateral bend (LB), and axial rotation (AR). STUDY DESIGN: An in vitro biomechanical study. METHODS: Eight cadaveric C2-C5 spines were used in this study. A custom-developed spinal loading simulator applied independent FE, LB, and AR to the specimens at 3°/s up to ±1.5 Nm. Using an optical tracking system, data were collected for the intact specimen and after sequential surgical interventions of posterior ligamentous complex (PLC) disruption, unilateral capsular disruption, progressive resection of the inferior articular process of C3 by one-half, and finally complete resection of the inferior articular process of C3. The magnitude of segmental and overall range of motion (ROM) for each simulated movement along with the overall neutral zone (NZ) was analyzed using two-way repeated-measures analyses of variance and post hoc Student-Newman-Keuls tests (α=.05). RESULTS: An increase in ROM was evident for all movements (p<.001). Within FE, ROM increased after cutting only the PLC (p<.05). For AR, sectioning of the PLC and complete bony facet fracture increased ROM (p<.05). Lateral bend ROM increased after facet capsular injury and complete articular facet removal (p<.05). There was an overall effect of injury pattern on the magnitude of the NZ for both FE (p<.001) and AR (p<.001) but not for LB (p=.6); however, the maximum increase in NZ generated was only 30%. CONCLUSIONS: The PLC and facet complex are dominant stabilizers for FE and AR, respectively. The overall changes in both ROM and NZ were relatively small but consistent with an isolated posterior osteoligamentous complex injury of the Stage I flexion-distraction injury.

Remote inflammatory response in liver is dependent on the segmental level of spinal cord injury.

BACKGROUND: Traumatic spinal cord injury (SCI) triggers a systemic inflammatory response (SIR) that contributes to a high incidence of secondary organ complications, particularly after a cervical or high-level thoracic injury. Because liver plays a key role in initiating and propagating the SIR, the aim of this study was to assess the effects that SCI at differing segmental levels has on the intensity of the inflammatory response in the liver. METHODS: Using male Wistar rats, clip compression SCI was performed at the 4th thoracic (T4 SCI; high-level SCI) or the 12th thoracic (T12 SCI; low-level SCI) spinal cord segment. Sham-injured rats had a partial laminectomy, but no SCI. Leukocyte recruitment to the liver, hepatic blood flow, and hepatocellular injury/death were assessed using intravital microscopy and histology. Chemokine and cytokine concentrations were assessed in the liver. Outcomes were measured at 1.5 hours, 12 hours, and 24 hours after SCI. RESULTS: At 12 hours after injury, T4 SCI caused a threefold increase in hepatic leukocyte recruitment compared with T12 SCI (p < 0.05). T4 SCI induced 50% more hepatocyte injury than T12 SCI at 12 hours (p < 0.05). Hepatic blood flow decreased after SCI, but not after sham injury, and stayed decreased only after T4 SCI at 24 hours after injury. The T4 SCI-induced changes were accompanied by increases in the hepatic concentrations of interleukin-1ß, leptin, interleukin 10, and cytokine-induced neutrophil chemoattractant-1 at 1.5 hours. CONCLUSIONS: Our findings indicate that traumatic SCI triggers an acute SIR that contributes to hepatocellular injury. SCI-induced remote injury/dysfunction to the liver appears to be transient and is more robust after an upper thoracic SCI compared with a lower thoracic SCI.

Predicting the need for tracheostomy in patients with cervical spinal cord injury.

BACKGROUND: Approximately 75% of hospitalized patients with a cervical spinal cord injury (CSCI) will require intubation and mechanical ventilation (MV) because of compromised respiratory function. It is difficult to predict those CSCI patients who will require prolonged ventilation and therefore will most benefit from early tracheostomy. This study intended to show the benefits of tracheostomy, particularly early, and to identify predictors of prolonged MV after CSCI. METHODS: A retrospective review of patients aged 16 years and older with acute CSCI admitted to London Health Science Center from 1991 to 2010 was performed. Demographic data and clinical parameters were extracted from medical records and the trauma registry. Regression analysis was used to identify predictors of prolonged MV. RESULTS: There were 66 eligible patients of which 42 (62%) had a tracheostomy performed. Five patients (7.6%) remained ventilator dependent and seven (10.6%) died more than 7 days after injury secondary to sepsis. After adjusting for the number of ventilator days after injury, patients who had a tracheostomy had fewer pulmonary complications than those who did not have a tracheostomy (p = 0.001). Early tracheostomy resulted in fewer days on the ventilator and a shorter hospital stay. Clinical parameters that predicted MV to be required longer than 7 days were Injury Severity Score > 32, complete SCI, and a PAO2/FIO2 ratio < 300 3 days after MV was initiated. CONCLUSION: We recommend early tracheostomy if the Injury Severity Score is >32, the patient has a complete SCI, and the PAO2/FIO2 ratio is <300 3 days after MV was initiated. LEVEL OF EVIDENCE: Prognostic study, level III.

An anatomic study of the interspinous space of the lumbosacral spine.

PURPOSE: The purpose of this study is to quantify the interspinous anatomy at the L4/5 and L5/S1 levels. METHODS: One hundred reconstructed computer tomography scans of the lumbosacral spine were reviewed by two separate surgeons. Data were collected from the midline sagittal reconstructed image at the L4-5 and L5-S1 levels. Measurements obtained included the disc angle, anterior and posterior disc height, and maximum interspinous space in both the anterior-posterior and cephalad-caudal directions. The disc height and disc angle were correlated with the interspinous height. RESULTS: The mean age of the patients reviewed was 47 years (range: 16-91; standard deviation: 20). According to our data population, the average length of the interspinous space was larger at the L4-5 level (13 mm) than the L5-S1 level (9 mm). The interspinous height was similar between the two levels. A poor correlation existed between the disc height or disc angle and the interspinous height. There was no correlation between measurements and age. CONCLUSIONS: The interspinous space available, as defined by computer tomography, at the L5/S1 level, is less able to accommodate current interspinous devices compared to the adjacent L4/5 level. The limiting factor is the length of the sacral part of the L5-S1 interspinous space.

The effect of soft-tissue restraints after type II odontoid fractures in the elderly: a biomechanical study.

STUDY DESIGN: A biomechanical analysis of soft-tissue restraints to passive motion in odontoid fractures. OBJECTIVE: To quantify the role of the C1-C2 facet joint capsules and anterior longitudinal ligaments (ALLs) in the setting of a type II odontoid fracture in the elderly. SUMMARY OF BACKGROUND DATA: The odontoid process itself is the primary stabilizer at the C1-C2 level; however, little is known about the role of the soft-tissue structures that remain intact in the setting of an odontoid fracture after a low-energy mechanism. METHODS: Ten cadaveric C0-C2 spinal segments were studied. Specimens were tested under simulated axial rotation with an applied moment of ±1 Nm and with an application of a 10 N anteriorly directed force to the body of C2 to induce sagittal translation. Optical motion data were initially collected for the intact state and after a simulated dens fracture. The specimens were then divided into 2 groups, where 1 group underwent unilateral and then bilateral C1-C2 facet capsular injuries followed by an ALL injury. The second group underwent the ALL injury before the same capsular injuries. Changes in axial range of motion and C1-C2 translation were analyzed using 2-way repeated measures analyses of variance and post hoc Student-Newman-Keuls tests (α = 0.05). RESULTS: In axial rotation, there was an increase in range of motion by approximately 13%, with the fracture of the dens compared with the intact state (P < 0.05). An increase was also present for each subsequent soft-tissue injury state compared with the previous (P < 0.05); however, there was no difference found between the 2 sectioning protocols. For sagittal translation testing, it was found that the odontoid fracture alone showed an increase of 3 mm of C1-C2 translation compared with intact (P < 0.05). Further soft-tissue injuries did not show an increase until the complete injury state. CONCLUSION: This study identifies that type II odontoid fractures without associated soft-tissue injury may be stable under certain loading modes.