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BACKGROUND: No prior work has explored whether the presence of degenerative spondylolisthesis impacts patient-reported outcome measurements (PROMs) after an anterior cervical discectomy and fusion (ACDF); therefore, the goal of the current study was to determine whether the presence of a spondylolisthesis affects PROMs after an ACDF. METHODS: A retrospective cohort study was conducted on patients over the age of 18 who underwent a 1- or 2-level ACDF. All patients received preoperative standing lateral x-rays and were placed into 1 of 2 groups based on the presence of cervical spondylolisthesis from C2-T1: (1) no spondylolisthesis (NS) group or (2) spondylolisthesis (S) group. Preoperative, postoperative, and delta (postoperative minus preoperative) were recorded and compared between groups via univariate and multivariate analysis. Outcomes reported were the Physical Component Scores of the Short Form-12 (PCS-12), the Mental Component Scores of the Short Form-12 (MCS-12), the Neck Disability Index (NDI), and visual analog scale (VAS) Arm/Neck. RESULTS: A total of 202 patients were included in the final analysis with 154 in the NS group and 48 in the S group. Both patient cohorts reported significant postoperative improvement in PCS-12, NDI, and VAS Arm/Neck. When comparing outcome scores between groups, only MCS-12 delta scores were different between groups, with the S group exhibiting a greater mean delta score (8.3 vs 1.3, P = 0.024) than the NS group after ACDF. Multiple linear regression analysis indicated having spondylolisthesis at baseline was a significant predictor of greater change in MCS-12 than the NS group (β = 4.841; 95% CI, 0.876, 8.805; P = 0.017). CONCLUSION: Both groups demonstrated significant postoperative improvement in PCS-12, NDI, or VAS Neck/Arm pain scores with no significant differences between groups. Patients with spondylolisthesis were found to have significantly greater improvement scores in MCS-12 scoring than those without spondylolisthesis after ACDF surgery.

Degenerative disc disease and associated cervical spondylosis or stenosis are common conditions encountered in clinical practice. These conditions may cause progressive cervical radicular or myelopathic symptoms leading to significant impairment. Although anterior cervical discectomy and fusion (ACDF) has been a reliable surgical treatment of cervical myelopathy and radiculopathy, but limitations include loss of cervical range of motion, the concern for adjacent segment degeneration and disease, pseudoarthrosis, complications related to the choice of intervertebral graft, dysphagia, as well as standard anterior cervical approach risk. Cervical total disc arthroplasty has emerged as an alternative operative procedure to ACDF.

Study design This was a prospective cohort study. Objective The objective of this study was to design and test a novel spine neurological examination adapted for telemedicine. Summary of background data Telemedicine is a rapidly evolving technology associated with numerous potential benefits for health care, especially in the modern era of value-based care. To date, no studies have assessed whether. Methods Twenty-one healthy controls and 20 patients with cervical or lumbar spinal disease (D) were prospectively enrolled. Each patient underwent a telemedicine neurological examination as well as a traditional in-person neurological examination administered by a fellowship trained spine surgeon and a physiatrist. Both the telemedicine and in-person tests consisted of motor, sensory, and special test components. Scores were compared via univariate analysis and secondary qualitative outcomes, including responses from a satisfaction survey, were obtained upon completion of the trial. Results Of the 20 patients in the D group, 9 patients had cervical disease and 11 patients had lumbar disease. Comparing healthy control with the D group, there were no significant differences with respect to all motor scores, most sensory scores, and all special tests. There was a high rate of satisfaction among the cohort with 92.7% of participants feeling "very satisfied" with the overall experience. Conclusions This study presents the development of a viable neurological spine examination adapted for telemedicine. The findings in this study suggest that patients have comparable motor, sensory, and special test scores with telemedicine as with a traditional in-person examination administered by an experienced clinician, as well as reporting a high rate of satisfaction among participants. To our knowledge, this is the first telemedicine neurological examination for spine surgery. Further studies are warranted to validate these findings.

Study Design: Retrospective cohort study. Objective: The goal of this study was to determine whether the absolute size (mm2), relative size (% canal compromise), or location of a single-level, lumbar disc herniation (LDH) on axial and sagittal cuts of magnetic resonance imaging (MRI) were predictive of eventual surgical intervention. Methods: MRIs of 89 patients were reviewed, and patients were split into groups based on type of management received (34 nonoperative vs 55 microdiscectomy). Radiographic characteristics—including size of disc herniation (mm2), size of spinal canal (mm2), location of herniation on axial (central, paracentral, foraminal) and sagittal (disc level, suprapedicle, pedicle, infrapedicle) planes, and type of herniation (bulge, protrusion, extrusion, sequestration)—were measured by 2 independent, orthopedic spine fellows and compared between groups via univariate and multivariate analyses. Results: The operative group showed a significantly higher percentage of canal compromise (39.5% vs 31.1%, P = .001) compared to the nonoperative group. Multiple logistic regression analysis showed higher odds of eventual operative intervention for a disc protrusion (odds ratio [OR] 6.30 [1.99, 19.86], P = .002) or disc extrusion (OR 11.5 [1.63, 81.2], P = .014) for Rater 1 and a higher odds of eventual surgical management for a paracentral location for both Rater 1 and Rater 2 (OR = 3.39 [1.25, 9.22], P = .017, and OR = 5.46 [1.77, 16.8], P = .003, respectively). Conclusions: Disc herniations in a paracentral location were more likely to undergo operative treatment than those more centrally located, on axial MRI views.

BACKGROUND: The presence of predominant pain in the arm vs the neck as a predictor of postoperative outcomes after anterior cervical discectomy and fusion (ACDF) has been seldom reported; therefore, the purpose of this study was to determine whether patients with predominant neck pain improve after surgery compared to patients with predominant arm pain or those with mixed symptoms in patients undergoing ACDF for radiculopathy. METHODS: A retrospective cohort study was conducted on patients who underwent ACDF at a single center from 2016 to 2018. Patients were split into groups based on preoperative neck and arm pain scores: neck (N) pain dominant group (visual analog scale [VAS] neck ≥ VAS arm by 1.0 point); neutral group (VAS neck < VAS arm by 1.0 point); or arm (A) pain dominant group (VAS arm ≥ VAS neck by 1.0 point), using a threshold difference of 1.0 point. Subsequently, individuals were substratified into 2 groups based on the arm to neck pain ratio (ANR): non-arm pain dominant defined as ANR ≤1.0 and arm pain dominant (APD) defined as ANR >1.0. Patient-reported outcome measurements including Neck Disability Index (NDI), Physical Component Score-12, and Mental Component Score (MCS-12) were compared between groups. RESULTS: No significant differences between groups when stratifying patients using a threshold difference of 1.0 point. When stratifying patients using the ANR, those in the APD group had significantly higher postoperative MCS-12 (P = 0.008) and NDI (P = 0.011) scores. In addition, the APD group showed a greater magnitude of improvement for MCS-12 and NDI scores (P = 0.043 and P = 0.038, respectively). Multiple linear regression showed that the A and the APD groups were both independent predictors of improvement in NDI. CONCLUSION: Patients with dominant arm pain showed significantly greater improvement in terms of MCS-12 and NDI scores compared to patients with dominant neck pain. CLINICAL RELEVANCE: To compare the impact of ACDF on arm and neck pain in the context of cervical radiculopathy using patient-reported outcome measures as an objective measurement. LEVEL OF EVIDENCE: 3.

Degenerative lumbar disease can be addressed via an anterior or posterior approach, and with or without the use of an interbody cage. Although several studies have compared the type of approach and technique, there is a lack of literature assessing patient-reported outcome measures (PROMs) and radiographic parameters between different fusion techniques.To determine whether the surgical approach and fusion technique for lumbar degenerative disease had an effect on short-term PROMs and radiographic parameters.Retrospective Cohort Study.Three hundred and ninety-one patients who underwent a 1-3 level lumbar spine fusion procedure at a high-volume academic center were retrospectively identified. Patients were divided into three groups based on the type of fusion they underwent: posterolateral fusion (PLF), anterior lumbar interbody fusion (ALIF), or transforaminal lumbar interbody fusion (TLIF).PROMs: Short Form-12 (SF-12) Physical Component Score (PCS) and Mental Component Score (MCS), Oswestry Disability Index (ODI), Visual Analog Score (VAS) Back, VAS Leg. Spinopelvic measurements: Pelvic Tilt (PT), Sacral Slope (SS), Pelvic Incidence (PI), Lumbar Lordosis (LL), Segmental Lordosis (SL), PI-LL mismatch.Patients with less than 1-year follow-up were excluded from the cohort. Pre- and postoperative spinopelvic measurements were obtained for all patients. Univariate analysis (Chi-squared/Fisher's exact test or ANOVA test with post-hoc Bonferroni test) was used to compare among the three groups in the PROMs and radiographic spinopelvic parameters. Multiple linear regression was used to determine if fusion technique was an independent predictor of change in each patient outcome.Two hundred and sixteen patients were included in the PLF group, 33 patients in the ALIF group, and 142 patients in the TLIF group. The PLF group was significantly older at baseline (p.001) and had lower preoperative diagnosis rates of degenerative scoliosis and disc herniations (p.001), whereas the ALIF group underwent a higher proportion of three-level fusions (p.001). There was no significant difference in spinopelvic parameters preoperatively, however the ALIF group showed significantly more improvement in SL postoperatively (p=.004) than the PLF and TLIF groups. Within each group, SL improved for the PLF and ALIF groups (p=.002 for both), but not for the TLIF group (p=.238). Comparing patient outcomes, the ALIF group reported lower preoperative VAS Leg scores (p=.031), however, this difference resolved postoperatively. Stratifying for preoperative diagnosis, there were no significant differences in outcomes, except for a greater improvement in VAS Leg scores for degenerative scoliosis patients undergoing ALIF. Using multivariate analysis, fusion technique was not found to be a significant predictor of change in any patient outcome or in odds of revision.Lumbar degenerative disease can be treated with several different fusion techniques, however, the relationship between type of fusion and PROMs is not established. Based on the findings in this study, the ALIF group showed greater improvement in SL compared with the PLF and TLIF groups, however, there was no difference noted in overall LL, PI-LL mismatch or other spinopelvic parameters. Despite these radiographic findings, patient outcome measures remained similar between all three fusion types.

Study design Retrospective review of a prospectively maintained database. Objective Compare outcomes following anterior cervical decompression and fusion (ACDF) between patients with no adjacent level spondylolisthesis (NAS) and adjacent level spondylolisthesis (AS). Summary of background data There are no prior studies evaluating the effect of preoperative adjacent-level cervical spondylolisthesis on outcomes following anterior cervical discectomy and fusion (ACDF). Methods A retrospective review of consecutive patients who underwent ACDF for degenerative cervical disease was performed. Adjacent level spondylolisthesis was defined on radiographs as anterior displacement (> 1 mm) of the vertebra in relation to an adjacent "to be fused" level. Patients were categorized as either AS or NAS. Preoperative and 1-year postoperative outcomes including Short Form-12 Physical and Mental Component Scores, Neck Disability Index, Visual Analog Score for arm and neck pain, and rate of revision surgery were compared between the two groups. Radiographic changes were also analyzed for patients with AS. Results A total of 264 patients met the inclusion criteria. There were 53 patients (20.1%) with AS and 211 patients (79.9%) with NAS. Both groups improved significantly from baseline with respect to all patient outcomes and there were no significant differences between the two groups. After accounting for confounding variables, the presence of an AS was not a predictor of any postoperative outcome. Revision rates did not differ between the two groups. Conclusion Patients with an AS had similar postoperative clinical outcomes compared with NAS. Furthermore, the presence of an AS was not a predictor of poorer clinical outcomes. This is the first study to investigate the effect of AS in patients undergoing ACDF and suggests that an adjacent-level spondylolisthesis does not need to be included in a fusion construct if it is not part of the primary symptom generating pathology. Level of evidence 3.

Study Design: Retrospective cohort review Objectives: Cervical pseudarthrosis is a frequent cause of need for revision anterior cervical discectomy and fusion (ACDF) and may lead to worse patient-reported outcomes. The effect of proton pump inhibitors on cervical fusion rates are unknown. The purpose of this study was to determine if patients taking PPIs have higher rates of nonunion after ACDF. Methods: A retrospective cohort review was performed to compare patients who were taking PPIs preoperatively with those not taking PPIs prior to ACDF. Patients younger than 18 years of age, those with less than 1-year follow-up, and those undergoing surgery for trauma, tumor, infection, or revision were excluded. The rates of clinically diagnosed pseudarthrosis and radiographic pseudarthrosis were compared between PPI groups. Patient outcomes, pseudarthrosis rates, and revision rates were compared between PPI groups using either multiple linear or logistic regression analysis, controlling for demographic and operative variables. Results: Out of 264 patients, 58 patients were in the PPI group and 206 were in the non-PPI group. A total of 23 (8.71%) patients were clinically diagnosed with pseudarthrosis with a significant difference between PPI and non-PPI groups ( P = .009). Using multiple linear regression, PPI use was not found to significantly affect any patient-reported outcome measure. However, based on logistic regression, PPI use was found to increase the odds of clinically diagnosed pseudarthrosis (odds ratio 3.552, P = .014). Additionally, clinically diagnosed pseudarthrosis negatively influenced improvement in PCS-12 scores ( P = .022). Conclusions: PPI use was found to be a significant predictor of clinically diagnosed pseudarthrosis following ACDF surgery. Furthermore, clinically diagnosed pseudarthrosis negatively influenced improvement in PCS-12 scores.

C2 tilt and C2 slope are quick and easy measurements to obtain on lateral radiographs and may be used to determine overall cervical sagittal alignment; however, the influence of these measurements on patient outcomes has not been well established in literature.To determine if C2 tilt and/or C2 slope predict patient outcomes better compared with conventional radiographic measures after an anterior cervical discectomy and fusion (ACDF).Retrospective cohort study.A total of 249 patients who underwent 1 to 3 level ACDF to address radiculopathy and/or myelopathy at a single academic institution between 2011 and 2015 were identified. Patients with less than 1 year of follow-up were excluded.Patient Reported Outcomes: Neck Disability Index (NDI), Physical Component Score-12 (PCS-12), and Mental Component Score (MCS-12), Visual Analog Score (VAS) Neck and Arm scores Cervical radiographic measurements: C2 tilt, C2 slope, C2-C7 lordosis, cervical SVA, T1 slope, T1 slope minus cervical lordosis (TS-CL), and C2-C7 ROM METHODS: Pearson correlation tests were performed to assess for significant associations between radiographic measurements and patient outcomes. Multiple linear regression models were developed adjusting for demographics and radiographic parameters to determine which factors were predictive of patient outcomes.C2 tilt and TS-CL correlated with all postoperative physical outcome scores (NDI, PCS-12, VAS Neck and ARM; p.05), however no association was seen between C2 slope and postoperative outcomes. After accounting for the presence of subaxial deformity, C2 tilt and TS-CL remained strongly correlated to patient outcome scores. With multiple linear regression, C2 tilt was a significant predictor for NDI, whereas TS-CL was a significant predictor for PCS-12, VAS Neck and VAS Arm.C2 tilt significantly correlated with well-described conventional cervical parameters as well as postoperative physical outcomes measures, especially NDI, on multivariate analysis. C2 tilt may provide an easy and practical tool for predicting physical outcomes after ACDF.

Injuries to the spine comprise a high percentage of workplace injuries. Spine surgeons' evaluation of injured workers requires attention to facts specific to worker's compensation claims including whether the injury occurred in the scope of employment, whether a work incident was causally related to the injury, and whether the injury contributed to a significant degree to the patient's overall medical condition. An injured worker's compensation is subject to state-specific guidelines and is largely dependent on the degree of disability and whether the disability is temporary or permanent. Here, we review the background, organization, and key terms used in the worker's compensation system.

BACKGROUND: The Neck Disability Index (NDI) is a 10-item questionnaire about symptoms relevant to cervical spine pathology, originally validated in the physical therapy literature. It is unclear if all of the items apply to spine surgery. The purpose of this study was to determine if improvements in the composite NDI score or specific NDI domains are appropriate measures for tracking changes in physical function after surgical intervention for cervical spondylotic myelopathy (CSM). METHODS: A retrospective cohort review of patients treated at a major academic medical center was undertaken. Baseline and postoperative standardized outcome measurement scores, including composite NDI, NDI subdomain, and SF-12 physical component score (PCS), were collected. Wilcoxon signed-rank test was used to determine whether patients exhibited improvement in each of the outcome measures included. Multiple linear regression was performed to determine whether change in NDI composite or subdomain scores predicted change in physical function after surgery for CSM—compared with the well-validated PCS score—controlling for factors such as age, sex, etc. RESULTS: Baseline data were collected on 118 patients. All outcome measures exhibited significant improvement after surgery based on the Wilcoxon signed-rank test. On linear regression, work (β = −2.419 [−3.831, −1.006]; P = .001) and recreation (β = −1.354 [−2.640, −0.068]; P = .039), as well as the NDI composite score (β = −0.223 [−0.319, −0.127]; P

STUDY DESIGN A retrospective cohort study. OBJECTIVE The objective of this study was to determine if patient satisfaction is predicted by improvement in health-related quality of life (HRQOL) metrics. SUMMARY OF BACKGROUND DATA Patient satisfaction is becoming an increasingly common proxy for treatment quality; however, the correlation between patient satisfaction and HRQOL outcome metrics following a lumbar disk herniation is unclear. METHODS Patients enrolled in the Spine Patient Outcomes Research Trial (SPORT) study were prospectively enrolled at 13 institutions. A retrospective subgroup analysis of prospectively collected data from the SPORT trial was performed. Receiver operating characteristic curves were used to determine if improvement in HRQOL metrics could accurately identify patient satisfaction. HRQOL metrics included: Short Form-36 (SF-36), Oswestry Disability Index (ODI), Sciatica Bothersomeness Index, Back Pain Bothersomeness Scale, and Leg Pain Bothersomeness Scale. RESULTS A total of 709 patients who underwent surgery and 319 patients treated without surgery were included. In the surgical cohort, receiver operating characteristic curve analysis demonstrated that SF-36 Physical Component Summary improvement had moderate accuracy [area under the curve (AUC)=0.77 (95% confidence interval, CI: 0.73-0.82)] at predicting satisfaction at 3 months, and it had excellent accuracy at predicting satisfaction at 2 years [AUC=0.81 (95% CI: 0.77-0.85)] and 4 years [AUC=0.81 (95% CI: 0.76-0.85)]. Absolute Physical Component Summary score had excellent accuracy at 3 months [AUC=0.83 (95% CI: 0.79-0.87)], 2 years [AUC=0.87 (95% CI: 0.84-0.9)] and 4 years [AUC=0.84 (95% CI: 0.8-0.89)]. Similarly improvement in the ODI had moderate accuracy of predicting satisfaction at 3 months [AUC=0.77 (95% CI: 0.72-0.81)], 2 years [AUC=0.78 (95% CI: 0.74-0.82)] and 4 years [AUC=0.78 (95% CI: 0.73-0.83)], and the absolute ODI score had excellent accuracy at 3 months [AUC=0.85 (95% CI: 0.82-0.89)], 2 years [AUC=0.89 (95% CI: 0.86-0.92)], and 4 years [AUC=0.88 (95% CI: 0.85-0.92)]. CONCLUSIONS HRQOL metrics can accurately predict patient satisfaction with symptoms at 3 months, 2 years, and 4 years after surgical intervention for a lumbar disk herniation. Absolute outcome scores were somewhat more predictive than change scores.

This is a retrospective cohort study.The objective of this study was to further elucidate the relationship between pelvic incidence-lumbar lordosis (PI-LL) mismatch and surgical outcomes in patients undergoing short segment lumbar fusions for degenerative lumbar disease.There are few studies examining the relationship between spinopelvic parameters and patient reported outcome measurements (PROMs) in short segment lumbar degenerative disease.A retrospective review was conducted at single academic institution. Patients undergoing 1- or 2-level lumbar fusion were retrospectively identified and separated into 2 groups based on postoperative PI-LL mismatch ≤10 degrees (NM) or PI-LL mismatch10 degrees (M). Outcomes including the Physical Component Score (PCS)-12, Mental Component Score (MCS)-12, Oswestry Disability Index (ODI), Visual Analog Scale (VAS) back and leg scores were analyzed. Absolute PROM scores, the recovery ratio and the percentage of patients achieving minimum clinically important difference between groups were compared and a multiple linear regression analysis was performed.A total of 306 patients were included, with 59 patients in the NM group and 247 patients in the M group. Patients in the M group started with a higher degree of PI-LL mismatch compared with the NM group (22.2 vs. 7.6 degrees, P0.001) and this difference increased postoperatively (24.7 vs. 2.5 degrees, P0.001). There were no differences between the 2 groups in terms of baseline, postoperative, or Δ outcome scores (P0.05). In addition, having a PI-LL mismatch was not found to be an independent predictor of any PROM on multivariate analysis (P0.05).The findings in this study show that even though patients in the M group had a higher degree of mismatch preoperatively and postoperatively, there was no difference in PROMs.Level III.

Study Design Retrospective review. Purpose To identify the trends in stimulator use, pair those trends with various grafting materials, and determine the influence of stimulators on the risk of revision surgery. Overview of Literature A large number of studies has reported beneficial effects of electromagnetic energy in healing long bone fractures. However, there are few clinical studies regarding the use of electrical stimulators in spinal fusion. Methods We used insurance billing codes to identify patients with lumbar disc degeneration who underwent anterior lumbar interbody fusion (ALIF). Comparisons between patients who did and did not receive electrical stimulators following surgery were performed using logistic regression analysis, chi-square test, and odds ratio (OR) analysis. Results Approximately 19% of the patients (495/2,613) received external stimulators following ALIF surgery. There was a slight increase in stimulator use from 2008 to 2014 (multi-level R2=0.08, single-level R2=0.05). Patients who underwent multi-level procedures were more likely to receive stimulators than patients who underwent single-level procedures (p0.05), except those in the multilevel ALIF+PLF cohort, wherein the patients who underwent stimulation had higher rates of revision surgery. Conclusions Concurrent PLF or multi-level procedures increased patients’ likelihood of receiving stimulators, however, the presence of comorbidities did not. Patients who received BMA plus autograft or allograft were more likely to receive stimulation. Patients with and without bone stimulators had similar rates of revision surgery.

Surgical site infection (SSI) following spine surgery can be devastating for both the patient and the surgeon. It leads to significant morbidity and associated health care costs, from readmissions, reoperations, and subsequent poor clinical outcomes. Complications associated with SSI following spine surgery include pseudarthrosis, neurological deterioration, sepsis, and death. Its management can be very challenging. The diagnosis of SSI involves the interpretation of combined clinical, laboratory, and occasionally radiologic findings. Most infections can be treated with an appropriate course of antibiotics and bracing if required. Surgical intervention is usually reserved for infections resistant to medical management, the need for open biopsy/culture, evolving spinal instability or deformity, and neurologic deficit or deterioration. A thorough knowledge of associated risk factors is required and patients should be stratified for risk preoperatively. The multifaceted approach of risk stratification, early diagnosis and effective treatment, is essential for successful prevention and effective treatment and crucial for a satisfactory outcome.

Study design Retrospective cohort study. Objective The objective of this study is to determine the reliability and clinical utility of the of the proposed CARDS classification for degenerative spondylolisthesis. Background The Clinical and Radiographic Degenerative Spondylolisthesis (CARDS) classification system was recently proposed as an alternative to the Meyerding system for classifying degenerative spondylolisthesis (DS). Unlike Meyerding, CARDS considers other relevant radiographic findings such as disk space collapse and segmental kyphosis to stratify DS into 4 radiographically discreet types. Currently, no studies have been conducted to assess the clinical utility of the CARDS system. Methods A total of 78 consecutive surgical patients with L4-L5 DS were rated as CARDS types A through D and Fleiss' κ for interobserver agreement was calculated. Then, demographics as well as preoperative and postoperative outcome scores (ODI, SF-12 mental and physical, VAS) were collected. The Kruskal-Wallis test was used to detect significant differences amongst CARDS types. An unpaired t test was used to compare individual CARDS types with all other subtypes combined. Results Grading showed: 4 type A, 19 type B, 45 type C, and 8 type D (k=0.63). There was a statistically significant difference in preoperative back pain (P=0.046) between groups. CARDS type D had the highest mean back pain scores (8.8) of all subtypes which was significantly higher than mean back pain for all other subtypes combined (P=0.016). CARDS D showed the largest degree of improvement in all outcome measures. There was a trend towards an increased improvement in ODI (P=0.074) and SF-12 MCS (P=0.095) in the CARDS D subtype relative to the rest of the cohort. Conclusions The CARDS classification system represents a reliable method for classifying cases of DS. Our results indicate that kyphotic segmental alignment (CARDS D) may be a less common, yet clinically distinct subset of DS characterized by worse preoperative back pain. CARDS type D cases may also show a greater degree of improvement in multiple outcome measures following surgical intervention.

Study design Retrospective analysis of prospective data from the degenerative spondylolisthesis (DS) arm of the Spine Patient Outcomes Research Trial. Objective The aim of this study was to identify risk factors for reoperation in patients treated surgically for DS and compare outcomes between patients who underwent reoperation with nonreoperative patients. Summary of background data Several studies have examined outcomes following surgery for DS, but few have identified risk factors for reoperation. Methods Analysis included patients with neurogenic claudication (>12 weeks), clinical neurological signs, spinal stenosis, and DS on standing lateral x-rays. Univariate and multivariate analyses were used to investigate patient characteristics and risk factors. Treatment effects (TEs) were calculated and compared between study groups. Results Of 406 patients, 72% underwent instrumented fusion, 21% noninstrumented fusion, and 7% decompression alone. At 8 years, the reoperation rate was 22%, of which 28% occurred within 1 year, 54% within 2 years, 70% within 4 years, and 86% within 6 years. The reasons for reoperation included recurrent stenosis or progressive spondylolisthesis (45%), complications such as hematoma, dehiscence, or infection (36%), or new condition (14%). Reoperative patients were younger (62.2 vs. 65.3, P = 0.008). Significant risk factors were use of antidepressants (P = 0.008, hazard ratio [HR] 2.08) or having no neurogenic claudication upon enrollment (P = 0.02, HR 1.82). Patients who were smokers, diabetics, obese, or on workman's compensation were not at greater risk for reoperation. At 8-year follow-up, scores for SF-36 bodily pain (BP), Oswestry Disability Index, American Academy of Orthopaedic Surgeons/Modems version (ODI), and stenosis frequency index were better in nonreoperative patients. TE favored nonreoperative patients for SF-36 BP, physical function, ODI, Stenosis Bothersomeness Index, and satisfaction with symptoms (P Conclusion The incidence of reoperation for patients with DS was 22% 8 years following surgery. Patients with a history of no neurogenic claudication and patients taking antidepressants were more likely to undergo reoperation. Outcome scores and TE were more favorable in nonreoperative patients. Level of evidence 2.

Background Spine surgery is complicated by an incidence of 1% to 9% of surgical site infection (SSI). The most common organisms are gram-positive bacteria and are endogenous, that is are brought to the hospital by the patient. Efforts to improve safety have been focused on reducing SSI using a bundle approach. The bundle approach applies many quality improvement efforts and has been shown to reduce SSI in other surgical procedures. Objective To provide a narrative review of practical solutions to reduce SSI in spine surgery. Methods Literature review and synthesis to identify methods that can be used to prevent SSI. Results SSI prevention starts with proper patient selection and optimization of medical conditions, particularly reducing smoking and glycemic control. Screening for staphylococcus organisms and subsequent decolonization is a promising method to reduce endogenous bacterial burden. Preoperative warming of patients and timely administration of antibiotics are critical to prevent SSI. Skin preparation using chlorhexidine and alcohol solutions are recommended. Meticulous surgical technique and maintenance of sterile techniques should always be performed. Postoperatively, traditional methods of tissue oxygenation and glycemic control remain essential. Newer wound care methods such as silver impregnation dressing and wound-assisted vacuum dressing are encouraging but need further investigation. Conclusion Significant reduction of SSIs is possible, but requires a systems approach involving all stakeholders. There are many simple and low-cost components that can be adjusted to reduce SSIs. Systematic efforts including understanding of pathophysiology, prevention strategies, and system-wide quality improvement programs demonstrate significant reduction of SSI.

Retrospective case series.To identify specific magnetic resonance imaging (MRI) characteristics of epidural fluid collections associated with infection, hematoma, or cerebrospinal fluid (CSF).Interpretation of postoperative MRI can be challenging after lumbar fusion. The purpose of this study was to identify specific MRI characteristics of epidural fluid collections associated with infection, hematoma, or CSF.The study population includes consecutive patients between 2006 and 2010 who had MRIs performed within 2 weeks after elective surgery for evaluation of possible CSF fluid collection, hematoma, or infection. Patients with known previous infection (discitis/osteomyelitis) or inadequate MRIs were excluded from the study. Medical records were reviewed to determine the diagnosis (infection, hematoma, or pseudomeningocele) underlying the fluid collection. MRIs were retrospectively evaluated by a musculoskeletal radiologist and orthopedic spine attending who were blinded to the pathologic diagnosis for characteristics of the fluid collection. MRI characteristics include location of lesion: osseous involvement, disk location, anterior versus posterior versus anteroposterior, soft-tissue involvement, and iliopsoas involvement. Characteristics of the lesion include: volume of lesion, loculation, satellite lesions, multiple loci, destructive characteristics, and mass effect upon thecal sac. Enhancement was scored based upon the following variables: rim enhancement, smooth versus irregular, thin versus thick, heterogeneity, diffuse enhancement, nonenhancement, and rim thickness. General fluid collection intensity and complexity on T1, T2, and T1 postcontrast images was scored as high, medium, and low. The χ test was used to compare the incidence of imaging characteristics between patient groups (infection, hematoma, and CSF).Thirty-three patients were identified who met inclusion criteria. There were 13 (39%) with infection, 9 (27%) with hematoma, and 11 (33%) with CSF collection. Factors that were associated with infection were osseous involvement (R=0.392, P=0.024) and destructive characteristics (R=0.461, P=0.007). Factors that were correlated with hematoma include mass effect (R=0.515, P=0.002) and high T1-signal intensity (R=0.411, P=0.019), absence of thecal sac communication (R=-0.389, P=0.025), and absence of disk involvement (R=-0.346, P=0.048). Pseudomeningocele was associated with thecal sac communication (R=0.404, P=0.02), absence of mass effect (R=-0.48, P=0.005), low T1 signal (R=-0.364, P=0.04), and low T2 complexity (R=-0.479, P=0.005).Specific characteristics of the postoperative MRI can be used to distinguish infection from noninfectious fluid collections. The strongest predictors of infection were osseous involvement and destructive bony changes. Hematoma was associated with mass effect on the thecal sac, high T1-signal intensity, and absence of thecal sac communication and disk involvement. CSF collections were distinguished by absence of mass effect, low T2-signal complexity, low T1-signal intensity, and communication with the thecal sac.

Study design A retrospective subgroup analysis was performed on surgically treated patients from the lumbar spinal stenosis (SpS) arm of the Spine Patient Outcomes Research Trial (SPORT), randomized, and observational cohorts. Objective To identify risk factors for reoperation in patients treated surgically for SpS and compare outcomes between patients who underwent reoperation with those who did not. Summary of background data SpS is one of the most common indications for surgery in the elderly; however, few long-term studies have identified risk factors for reoperation. Methods A post-hoc subgroup analysis was performed on patients from the SpS arm of the SPORT, randomized and observational cohorts. Baseline characteristics were analyzed between reoperation and no-reoperation groups using univariate and multivariate analysis on data 8 years postoperation. Results Of the 417 study patients, 88% underwent decompression only, 5% noninstrumented fusion, and 6% instrumented fusion. At the 8-year follow-up, the reoperation rate was 18%; 52% of reoperations were for recurrent stenosis or progressive spondylolisthesis, 25% for complication or other reason, and 16% for new condition. Of patients who underwent a reoperation, 42% did so within 2 years, 70% within 4 years, and 84% within 6 years. Patients who underwent reoperation were less likely to have presented with any neurological deficit (43% reop vs. 57% no reop, P = 0.04). Patients improved less at follow-up in the reoperation group (P Conclusion In patients undergoing surgical treatment for SpS, the reoperation rate at 8-year follow-up was 18%. Patients with a reoperation were less likely to have a baseline neurological deficit. Patients who did not undergo reoperation had better patient reported outcomes at 8-year follow-up compared with those who had repeat surgery. Level of evidence 2.

Background: Perforations of the pedicle wall during cannulation can occur with experienced surgeons. Direct endoscopic visualization has not been used to inspect pedicles previously due to bone bleeding obscuring the camera visualization. The hypothesis of this study was that endoscopic visualization of pedicle wall integrity was technically feasible and would enable identification of clinically significant pedicle breaches. Methods: A live porcine model was used. Eight lumbar pedicles were cannulated. Clinically significant breaches were created. An endoscope was introduced and was used to inspect the pedicles. Results: All lumbar pedicles were endoscopically visible at a systolic pressure of 100 mm Hg. Clinically relevant anatomic structures and iatrogenic pathology, such as medial, lateral, and anterior breaches, were identified. There were no untoward events resulting from endoscopic inspection of the pedicle endosteal canal. Conclusions: Endoscopic inspection of lumbar pedicles was safe and effective. The findings on endoscopic inspection corresponded with the ball-tip probe palpation techniques. Additional techniques, such as selection between 2 tracts, was possible with the endoscopic technique.

Identifying appropriate candidates for lumbar spine fusion is a challenging and controversial topic. The purpose of this study was to identify baseline characteristics related to poor/favorable outcomes at 1 year for a patient who received lumbar spine fusion.The aims of this study were to describe baseline characteristics of those who received lumbar surgery and to identify baseline characteristics from a spine repository that were related to poor and favorable pain and disability outcomes for patient who received lumbar fusion (with or without decompression), who were followed up for 1 full year and discriminate predictor variables that were either or in contrast to prognostic variables reported in the literature.This study analyzed data from 2710 patients who underwent lumbar spine fusion. All patient data was part of a multicenter, multi-national spine repository. Ten relatively commonly captured data variables were used as predictors for the study. Univariate/multivariate logistic regression analyses were run against outcome variables of pain/disability.Multiple univariate findings were associated with pain/disability outcomes at 1 year including age, previous surgical history, baseline disability, baseline pain, baseline quality of life scores, and leg pain greater than back pain. Notably significant multivariate findings for both pain and disability include older age, previous surgical history, and baseline mental summary scores, disability, and pain.Leg pain greater than back pain and older age may yield promising value when predicting positive outcomes. Other significant findings may yield less value since these findings are similar to those that are considered to be prognostic regardless of intervention type.

Background The Spine Patient Outcomes Research Trial (SPORT) evaluated the effects of surgery versus nonoperative treatment for lumbar intervertebral disc herniation (IDH), among other pathologies. Multiple subgroup analyses have been completed since the initial publications, which have further defined which patient factors lead to better or worse patient-reported outcomes; however, the degree to which these factors influence patient-reported outcomes has not been explored.

Retrospective analysis of prospectively collected data.To determine which, if any, radiographic parameters are predictive of clinical outcome after cervical disk replacement (CDR) surgery.It is unclear whether radiographic parameters are predictive of outcome after CDR.An analysis of the radiographic parameters and clinical outcomes of the CDR cohort of the Discover artificial cervical disk IDE trial was performed. Clinical outcome measures included Neck Disability Index (NDI), visual analog pain scale (neck, arm, and shoulder), and SF-36 physical component summary score scores, collected preoperatively and at regularly scheduled postoperative time periods. Patients with at least 1-year follow-up were included. The change in outcomes from baseline was determined at each follow-up interval. The following minimal clinically important difference (MCID) thresholds were applied: -7.5 for NDI, -25 for visual analog pain scale, and +4.1 for physical component summary score. Fifty-six radiographic variables were analyzed to identify factors that may be associated with a poor clinical outcome, defined as failure to achieve the MCID in NDI.A total of 243 patients underwent CDR at 304 levels (182 one level, 61 two level). One hundred seventy-one patients (89 female, 82 male; mean age, 44.2 y; range, 28-67 y) had at least 1-year follow-up. A preoperative disk height of3.5 mm was associated with a 3.4 times greater risk of not achieving a MCID in NDI (P=0.018). Increasing the functional spinal unit angle by3 degrees was associated with a 3.5 times greater risk of not achieving a MCID in NDI (P=0.016). There were 21/171 patients (25 levels) who did not achieve the NDI MCID threshold. All of these patients had at least1, and 16/21 of these patients had more than 1 abnormal radiographic finding. Seventy percent of treatment levels had severe or bridging heterotopic ossification at 3-years follow-up, the incidence of which increased linearly with time.Several radiographic variables are predictive of clinical outcomes, including decreased preoperative disk space height and excessive postoperative segmental lordosis.

Retrospective review.(1) To describe change in treatment patterns for degenerative spondylolisthesis (DS). (2) To report regional variation in treatment of DS. (3) To describe variation in surgeon-reported outcomes for DS based on treatment.Spinal stenosis associated with DS is commonly treated with decompression and fusion but little is known about the optimal fusion technique. During a 6-month period, American Board of Orthopaedic Surgery step II candidates submit procedure lists; these lists have been stored in an electronic database since 1999.The American Board of Orthopaedic Surgery database was retrospectively queried to identify patients who underwent surgery for DS from 1999 to 2011. Included patients underwent uninstrumented fusion, fusion with posterior instrumentation, fusion using interbody device, or decompression without fusion. Utilization of these procedures was analyzed by year and geographic region.The study period included 5639 cases; the annual number of cases doubled during the study period. The percentage of cases treated with interbody fusion (IF) increased significantly throughout the study period, from 13.6% (1999-2001) to 32% (2009-2011) (P0.001). The percentage of DS cases treated with posterolateral fusion peaked in 2003 then decreased as the rate of IF increased. In 2011, the rates of posterolateral fusion (40%) and posterolateral fusion with IF (37%) were nearly identical. The Northwest had the highest rate of IF (41%),10% higher than any other region (P0.001) and more than 23% higher than the Southeast (P0.001).Despite little evidence guiding treatment strategy for DS, national treatment patterns have changed dramatically during the past 13 years. The rapid adoption of IF and substantial regional variation in treatment utilization patterns raises questions about drivers of change including perceptions about associated fusion rates, the importance of sagittal balance and differential reimbursement.4.

Background context Treatment of Type II odontoid fractures remains controversial, whereas nonoperative treatment is well accepted for isolated Type III odontoid fractures. Little is known about long-term sequelae of nonoperative management or risk of recurrent injury after nonsurgical treatment. We hypothesize that a substantial proportion of odontoid fractures assumed to be acute are actually chronic injuries and have a high rate of late displacement resulting in neurologic injury. Purpose To identify patients presenting with previously unrecognized odontoid fracture nonunions and to document the incidence of new neurologic injury after secondary trauma in this population. Study design Retrospective case series. Patient sample One hundred thirty-three patients with Type II odontoid fractures presenting to a Level I trauma center. Outcome measures Computed tomography (CT) and magnetic resonance imaging (MRI) scans, American Spinal Injury Association Motor Score (AMS), and neurologic examination. Methods All patients presenting after traumatic injury to a Level I trauma center from May 2005 to May 2010 with a Type II odontoid fracture on CT scan were included. Patients aged less than 18 years and those with pathologic fractures were excluded. Fractures were classified as chronic or acute based on CT evidence of chronic injury/nonunion including fracture resorption, sclerosis, and cyst formation. Magnetic resonance imaging was then examined for evidence of fracture acuity (increased signal in C2 on T2 images). Patients without evidence of acute fracture on MRI were considered to have chronic injuries. Computed tomography and MRI scans were interpreted independently by two reviewers. Chart review was performed to document demographics, AMS, and new-onset neurologic deficit associated with secondary injury. Results One hundred thirty-three patients presented with Type II odontoid fractures and no known history of cervical fracture with an average age of 79 years. Based on CT criteria, 31/133 (23%) fractures were chronic injuries. Nine additional fractures appeared acute on CT but were determined to be chronic by MRI findings. The overall number of chronic fractures was therefore 40 (30%). Interobserver reliability analysis for classification of fractures as chronic demonstrated κ=0.65 representing substantial agreement. Of the 40 chronic fractures, 7 patients (17.5%) had new-onset neurologic deficits after secondary injury including 4 motor deficits, 2 sensory deficits, and 1 combined deficit. Although the chronic injury group as a whole had similar AMS to the acute injury group (89 vs. 84, p=.27), the seven patients with new-onset neurologic deficit had an average AMS of 52.4. Conclusions A substantial proportion of patients presenting after cervical trauma with Type II odontoid fractures have evidence of nonacute injury. Of these patients, 17% presented with a new neurologic deficit caused by an “acute-on-chronic” injury.

Objective Although hip alignment and spinal alignment have been studied individually, there is little information concerning the relationship between them. The questions addressed in this study are: (i) Is there a reproducible measure of sagittal plane acetabular orientation; (ii) Is sagittal plane acetabular orientation determined more by pelvic incidence (PI) or acetabular wall coverage? Methods Data on patients who had undergone screening by CT scan of the pelvis for non-orthopedic indications from 2005–2010 were retrospectively studied. There were 164 patients of mean age 59 years (range, 27–87). Patients with pelvic trauma, hip arthroplasty or other hip pathology were excluded. Measurements of relevant acetabular and spinopelvic variables were made in the sagittal plane. The sacro-acetabular angle (SA) was defined as the angle between a tangent line to the anterior and posterior walls of the acetabulum and the S1 endplate. Multiple regression analysis was used to determine which factors contribute to SA angle. Results The mean sacro-acetabular angle was 72° (SD = 14.8°). Center edge angles (CEAs) were measured at the anterior and posterior walls of the acetabulum. Mean anterior CEA was 69° (SD = 8.3°) and posterior CEA 107° (SD = 16.4°). Regression analysis revealed the largest significant predictors of SA angle were PI and A-CEA. Conclusions Sagittal acetabular orientation is related to spino-pelvic balance and morphological characteristics. Increased PI or posterior wall coverage corresponds to a more vertical acetabular orientation. Sagittal plane acetabular alignment may be an important variable in achieving favorable results after reconstruction.

Objective The study hypotheses were that: (i) there would be a difference in sagittal plane alignment between patients with symptomatic osteoarthritis of the hip and those with lumbar degenerative disk disease; and (ii) that sagittal plane lumbar alignment would change following total hip arthroplasty (THA). Methods In this prospective study, a series of patients without back pain or lumbar complaints who were scheduled to undergo THA underwent lateral lumbar radiography prior to and nine months after elective THA. Radiographic measurements of lumbar alignment included sacral slope, lumbar lordosis, and L1 axis S1 distance (L1 ASD). All measurements were performed on upright, standing, lateral radiographs. A control group of patients underwent serial radiography over the same period for evaluation of lumbar degenerative disease. The independent sample t-test was used to compare the mean sacral slope, lumbar lordosis, and L1 ASD in the THA and control groups. Results There were 12 patients in the THA group and 34 in the control group. Mean follow-up was 9 months. Average age in the control group was 63 years and in the THA group 64.2 years. The sacral slope was greater in the THA group (mean, 23°) than in the lumbar patients (control group) and this difference was statistically significant (mean, 11°, P = 0.001). There were no statistically significant differences between THA and control patients in lumbar lordosis or L1 ASD. Change before and after THA was measured. There were no statistically significant differences in assessed radiographic variables preoperatively versus postoperatively. Conclusion There is no significant change in spinal alignment after unilateral THA. At baseline, patients with symptomatic spine complaints have less sacral slope than their hip arthroplasty counterparts.

After a systematic review, six prospective studies comparing TDR versus ACDF were selected. These studies had between 2–5 years follow-up and reported revisions due to adjacent segment disease. The concern for adjacent segment disease (ASD) has led to the development of motion-preserving technologies such as total disc arthoplasty (TDA). However, numerous studies comparing ACDF versus TDA do not report the number of patients who develop symptoms attributable to an adjacent level or the number of revisions that occur at an adjacent level. Often the follow-up period is limited as well. A systematic review of IDE and non-IDE trials was performed using PubMed and Cochrane Libraries. These databases were thoroughly searched for prospective randomized studies comparing ACDF and TDR. Specifically, studies reporting clinical outcomes and symptomatic ASD with at least 2 years of follow-up were selected. Six studies met the inclusion criteria and are discussed in the review. Pooling data from six prospective studies, the overall sample size at baseline was 1586 (ACDF = 777, TDA=809) and at final follow-up was 1110, giving an overall follow-up of 70%. Of 1586 surgically treated patients, 51 (3.2%, ACDF=30, TDA=21) required revision surgery at an adjacent level at 2–5 years of follow-up. There was no data available on the incidence of ASD or the number of patients with ASD treated non-operatively. There has not been a study to date that has demonstrated a difference in the rate of ASD for ACDF versus TDR. There is a paucity of data from prospective studies regarding the incidence of ASD and the proportion of patients who go on to require further surgical intervention. Prospective studies should continue to focus on excellent patient follow-up and accurate assessment of patient symptoms as ASD has been under reported in prospective studies.

Objective The hypothesis of this study is that pelvic obliquity (PO) is associated with specific patterns of degenerative scoliosis. Methods This study was a retrospective case series of consecutive patients undergoing fusion for lumbar conditions (degenerative scoliosis or spondylolisthesis). The discrepancy in the iliac crest height, coronal L1-S1 endplate angles, distance from L1 coronal bisector to the sacral center, number of degenerative scoliosis curves, and individual curve angulations were measured. Results Limb length discrepancy was present in 87% of patients with a degenerative scoliosis. There were 116 patients with a single curve > 5° and PO > 2 cm. Of the patients with a single curve, the apex of scoliosis was opposite the high iliac crest side in 79% patients. There were 338 patients with a double curve. The apex of scoliosis was opposite the high iliac crest side in 48% of patients. Conclusion There were distinct patterns of limb length discrepancy corresponding to degenerative scoliotic curve morphology. In patients with single degenerative scoliotic curves, PO most commonly appeared to counteract the scoliotic curve and result in an overall decrease in trunk shift. This occurred because the high iliac crest was observed most commonly on the convex side of the scoliotic curve. This effect was not observed in double lumbar degenerative scoliotic curves.

Objective The Rule of Spence states that displacement of the C1 lateral masses by >6.9–8.1 mm suggests loss of transverse ligament integrity. The purpose of this study was to establish the thresholds of C1 displacement on CT scans that correspond to transverse ligament disruption. Methods Over four years, consecutive patients with acute C1 fractures with at least three fracture lines were analyzed. CT measurements and MRI were assessed by blinded observers for bony displacement in the axial (internal and external lateral mass separation), coronal and sagittal planes and transverse ligament integrity. Results Eighteen patients were studied. Mean CT bony measurements were as follows: internal border lateral mass separation (ILM) 23.3 ± 3.4 mm, external border lateral mass separation (ELM) 50.3 ± 4.3 mm, total C1 lateral mass overhang over the C2 superior process (LMO) 5.4 ± 1.3 mm. Twelve patients were identified as having intact transverse ligament and six had transverse ligament disruption. There was no difference in mean normalized ILM, ELM, or LMO between patients with or without transverse ligament integrity (P > 0.05). Conclusion There was no correlation between bony displacement and transverse ligament integrity. CT scans post-injury may not show the position of maximal displacement. If there is clinical concern about a possible transverse ligament injury, MRI should be performed.

Object Studies from many disciplines have found an association with the summer months, elevated temperature, humidity, and an increased rate of infection. The “July effect,” a hypothesis that the inexperience of new house staff at the beginning of an academic year leads to an increase in wound complications, has also been considered. Finally, an increase in trauma-related admissions in the summer months is likely to result in an increased incidence of postoperative infections. Two previous studies revealed mixed results concerning perioperative spinal wound infections in the summer months. The purpose of this study was to determine the months and/or seasons of the year that display significant fluctuation of postoperative infection rate in spine surgery. Based on the idea that infection rates are susceptible to seasonal factors, the authors hypothesized that spinal infections would increase during the summer months. Methods Inclusion criteria were all spine surgery cases at a single tertiary referral institution between January 2005 and December 2009; 8122 cases were included. Patients presenting with a contaminated wound or active infection were excluded. Infection rates were calculated on a monthly and seasonal basis and compared. Results A statistically significant increase in the infection rate was present on both a seasonal and monthly basis (p = 0.03 and p = 0.024) when looking at the seasonal change from spring to summer. A significant decrease in the infection rate was seen on a seasonal basis during the change from fall to winter (p = 0.04). The seasonal rate of infection was highest in the summer (4.1%) and decreased to the lowest point in the spring (2.8%) (p = 0.03). Conclusions At the authors' institution, spine surgeries performed during the summer and fall months were associated with a significantly higher incidence of wound infection compared with the winter and spring. These data support the existence of a seasonal effect on perioperative spinal infection rates, which may be explained by seasonal variation in weather patterns and house staff experience, among other factors.

Study design Retrospective analysis of a prospective cohort. Objective Change in cervical angular alignment may be associated with dysphagia. Summary of background data Bony deformities of the cervical spine may be associated with secondary contractures of soft tissues in the neck. Acute surgical deformity correction causes in changes in soft tissue tension in the anterior neck, resulting in dysphagia. Methods The study population included patients undergoing 1 and 2 level elective anterior cervical discectomy and fusion for cervical myelopathy or radiculopathy. Preoperative and postoperative radiographs at 2 weeks were measured by a blinded observer for C2-C7 endplate angle, C2-C7 posterior vertebral body length, and occipital condyle plumb line distance on upright lateral radiographs at 2, 6, and 12 weeks postoperatively. Patients were prospectively queried about dysphagia incidence and severity using a numeric rating scale. Multiple linear regression analysis was used to determine the effect of change in radiographic parameters controlling for demographic characteristics. Results The study population included 25 patients with complete radiographs. The mean change in C2-C7 angle was -0.6 degrees (SD 9), the mean change in C2-C7 length was 1.7 mm (SD 26), the mean change in occipital condyle plumb line distance was 2.3 mm (SD 20).Multiple linear regression analysis was performed including operative time, age, sex, number of levels, and change in radiographic parameters as independent variables and using dysphagia score as the dependent variable. The change in C2-C7 angle and operative time were the only statistically significant predictors of change in dysphagia at 2 and 6 weeks postoperatively. Conclusions These results indicate that lordotic change in spinal alignment and longer operative times are associated with increased postoperative dysphagia. Surgeons should counsel patients in whom a large angular correction is expected about the possibility for postoperative dysphagia. Furthermore, future studies on dysphagia incidence should include radiographic alignment as an independent predictor of dysphagia.

Background: There is considerable controversy about the long-term morbidity associated with the use of posterior autologous iliac crest bone graft for lumbar spine fusion procedures compared with the use of bone-graft substitutes. The hypothesis of this study was that there is no long-term difference in outcome for patients who had posterior lumbar fusion with or without iliac crest autograft. Methods: The study population includes patients enrolled in the degenerative spondylolisthesis cohort of the Spine Patient Outcomes Research Trial who underwent lumbar spinal fusion. Patients were divided according to whether they had or had not received posterior autologous iliac crest bone graft. Results: There were 108 patients who had fusion with iliac crest autograft and 246 who had fusion without iliac crest autograft. There were no baseline differences between groups in demographic characteristics, comorbidities, or baseline clinical scores. At baseline, the group that received iliac crest bone graft had an increased percentage of patients who had multilevel fusions (32% versus 21%; p = 0.033) and L5-S1 surgery (37% versus 26%; p = 0.031) compared with the group withoutiliaccrestautograft.Operativetimewashigherintheiliaccrestbone-graftgroup(233.4versus200.9minutes;p< 0.001), and there was a trend toward increased blood loss (686.9 versus 582.3; p = 0.057). There were no significant differences in postoperative complications, including infection or reoperation rates, between the groups. On the basis of the numbers available, no significant differences were detected between the groups treated with or without iliac crest bone graft with regard to the scores on Short Form-36, Oswestry Disability Index, Stenosis Bothersomeness Index, and Low Back Pain Bothersomeness Scale or the percent of patient satisfaction with symptoms averaged over the study period. Conclusions: The outcome scores associated with the use of posterior iliac crest bone graft for lumbar spinal fusion were not significantly lower than those after fusion without iliac crest autograft. Conversely, iliac crest bone-grafting was not associated with an increase in the complication rates or rates of reoperation. On the basis of these results, surgeons may choose to use iliac crest bone graft on a case-by-case basis for lumbar spinal fusion. Level of Evidence: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Background context Despite the importance of the information provided by cost-utility analyses (CUAs), there has been a lack of these types of studies performed in the area of spinal care. Purpose To systematically review cost-utility studies published on spinal care between 1976 and 2010. Study design Systematic review. Methods All CUAs pertaining to spinal care published between 1976 and 2010 were identified using the cost-effectiveness analysis (CEA) registry database (Tufts Medical Center, Institute for Clinical Research and Health Policy) and National Health Service Economic Evaluation Database (NHS EED). The keywords used to search both the registry databases were the following: spine, spinal, neck, back, cervical, lumbar, thoracic, and scoliosis. Search of the CEA registry provided a total of 28 articles, and the NHS EED yielded an additional 5, all of which were included in this review. Each article was reviewed for the study subject, methodology, and results. Data contained within the databases for each of the 33 articles were recorded, and the manuscripts were reviewed to provide insight into the funding source, analysis perspective, discount rate, and cost-utility ratios. Results There was wide variation among the 33 studies in methodology. There were 17 operative, 13 nonoperative, and 3 imaging studies. Study subjects included lumbar spine (n=27), cervical spine (n=4), scoliosis (n=1), and lumbar and cervical spine (n=1). Twenty-three of the studies were based on the clinical data from prospective randomized studies, 7 on decision models, 2 on prospective observational data, and 1 on a retrospective case series. Sixty cost-utility ratios were reported in the 33 articles. Of the ratios, 19 of 60 (31.6%) were cost saving, 27 of 60 (45%) were less than $100,000/quality-adjusted life year (QALY) gain, and 14 of 60 (23.3%) were greater than $100,000/QALY gain. Only four of 33 (12%) studies contained the four key criteria of cost-effectiveness research recommended by the US Panel on Cost-Effectiveness in Health and Medicine. Conclusions Thirty-three CUA studies and 60 cost-utility ratios have been published on various aspects of spinal care over the last 30 years. Certain aspects of spinal care have been shown to be cost effective. Further efforts, however, are needed to better define the value of many aspects of spinal care. Future CUA studies should consider societal cost perspective and carefully consider the durability of clinical benefit in determining a study time horizon.

Craniocervical dislocations are rare, potentially devastating injuries. A diagnosis of craniocervical dislocations may be delayed as a result of their low incidence and paucity of diagnostic criteria based on CT and MRI. Delay in diagnosis may contribute to neurological injury from secondary displacement resulting from instability. The purpose of this study was to define CT and MRI-based diagnostic criteria for craniocervical dislocations to facilitate early injury recognition and stabilization.Using CT and MRI, we (1) described the bony articular displacements characterize craniocervical injuries; (2) described the ligamentous injuries that characterize craniocervical injuries; and (3) determined whether neurologic injuries were associated with bony or ligamentous injury.Using a prospectively collected spinal cord injury database, we identified 18 patients with acute, traumatic occipitocervical injuries. We reviewed CT scans and MR images to document the height of the occipitoatlantal and atlantoaxial joints and integrity of craniocervical ligaments. Medical records were reviewed for neurological status. The primary measurements were number of patients with articular displacement, location of bony displacement, and number of patients with ligamentous injury.Thirteen of 18 patients had displacement outside the normal range. Six patients demonstrated displacement of both occipitoatlantal and atlantoaxial joints, whereas five patients presented with displacement through the atlantoaxial joints only. Two patients had an abnormal basion-dental interval only. Of 17 patients with MR images, the cruciate ligament was injured in 11 patients, indeterminate in four, and intact in two. All five patients with occipitoatlantal articular displacement had injury to the occipitoatlantal capsule. No patient had occipitoatlantal capsular injury without occipitoatlantal articular displacement. Three cases of complete spinal cord injury were found after occipitoatlantal-atlantoaxial dislocations. Three patients with occipitoatlantal-atlantoaxial dislocations were neurologically intact. The five patients with atlantoaxial dislocations and patients without displacement or ligamentous injury were neurologically intact. Five patients had cruciate ligament rupture or indeterminate injury but no joint diastasis.The occipitoatlantal joint capsules stabilize the occipitoatlantal joint; disruption of the occipitoatlantal capsule may suggest the presence of instability. Based on these findings, we identified two distinct injury patterns: isolated atlantoaxial injuries (Type I) and combined occipitoatlantal-atlantoaxial injuries (Type II). Occipitoatlantal joint capsule integrity differentiated these subsets and Type II injuries had a higher percentage of complete spinal cord injuries on presentation.

DuraSeal(™) (Coviden, Waltham, MA, USA), a hydrogel sealant, is primarily used as an adjunct to a dural repair. Its use has also been described to seal off an annulotomy after a transforaminal lumbar interbody fusion when recombinant human bone morphogenetic protein-2 (rhBMP-2) is used. This aids in the reduction of postoperative radiculitis caused by rhBMP-2. However, as a result of its hydrophilic properties, DuraSeal(™) has the potential to swell, which could lead to compression of the thecal sac.We report a 57-year-old woman who developed cauda equina after a transforaminal lumbar 47 interbody fusion (TLIF) procedure in which the expansion of the DuraSeal(™) was believed to be the causative factor. The patient developed urinary retention, bowel incontinence, and paresthesias in the saddle region on postoperative Day 3. She underwent emergent exploration and decompression of the thecal sac. The gel-like DuraSeal™ material was causing significant compression of the thecal sac.Multiple reports have documented that DuraSeal(™), used as an adjunct to dural repair, can swell leading to compression of the spinal cord and/or neural elements. Our case demonstrates the use of DuraSeal(™) both over a site of a dural repair and over an annulotomy site, through which a TLIF was performed, is associated with the risk of developing postoperative cauda equina syndrome as a result of swelling of the DuraSeal(™).Those using DuraSeal™ to seal off the annulotomy after a TLIF procedure performed with rhBMP-2 should use the product with an understanding of the potential postoperative swelling of the product and resulting neurologic sequela, particularly if DuraSeal(™) is used concomitantly at the site of dural repair.

Object The load-sharing score (LSS) of vertebral body comminution is predictive of results after short-segment posterior instrumentation of thoracolumbar burst fractures. Some authors have posited that an LSS > 6 is predictive of neurological injury, ligamentous injury, and the need for surgical intervention. However, the authors of the present study hypothesized that the LSS does not predict ligamentous or neurological injury. Methods The prospectively collected spinal cord injury database from a single institution was queried for thoracolumbar burst fractures. Study inclusion criteria were acute (< 24 hours) burst fractures between T-10 and L-2 with preoperative CT and MRI. Flexion-distraction injuries and pathological fractures were excluded. Four experienced spine surgeons determined the LSS and posterior ligamentous complex (PLC) integrity. Neurological status was assessed from a review of the medical records. Results Forty-four patients were included in the study. There were 4 patients for whom all observers assigned an LSS > 6, recommending operative treatment. Eleven patients had LSSs ≤ 6 across all observers, suggesting that nonoperative treatment would be appropriate. There was moderate interobserver agreement (0.43) for the overall LSS and fair agreement (0.24) for an LSS > 6. Correlations between the LSS and the PLC score averaged 0.18 across all observers (range −0.02 to 0.34, p value range 0.02–0.89). Correlations between the LSS and the American Spinal Injury Association motor score averaged −0.12 across all observers (range −0.25 to −0.03, p value range 0.1–0.87). Correlations describing the relationship between an LSS > 6 and the treating physician's decision to operate averaged 0.17 across all observers (range 0.11–0.24, p value range 0.12–0.47). Conclusions The LSS does not uniformly correlate with the PLC injury, neurological status, or empirical clinical decision making. The LSSs of only one observer correlated significantly with PLC injury. There were no significant correlations between the LSS as determined by any observer and neurological status or clinical decision making.

Study design Retrospective database review. Objective To determine whether surgical site infections are associated with case order in spinal surgery. Summary of background data Postoperative wound infection is the most common complication after spinal surgery, with incidence varying from 0.5% to 20%. The addition of instrumentation, use of preoperative prophylactic antibiotics, length of procedure, and intraoperative blood loss have all been found to influence infection rate. No previous study has attempted to correlate case order with infection risk after surgery. Methods A total of 6666 spine surgery cases occurring between January 2005 and December 2009 were studied. Subjects were classified into 2 categories: fusion and decompression. Case order was determined, with each procedure labeled 1 to 5 depending on the number of previous cases in the room. Variables such as the American Society of Anesthesiologists score, number of operative levels, wound class, age, sex, and length of surgery were also tracked. A step-down binary regression was used to analyze each variable as a potential risk factor for infection. Results Decompression cases had a 2.4% incidence of infection. Longer surgical time and higher case order were found to be significant risk factors for lumbar decompressions. Fusion cases had a 3.5% incidence of infection. Posterior approach and revision cases were significant risk factors for infection in cervical cases. For lumbar fusion cases, longer surgical time, higher American Society of Anesthesiologists score, and older age were all significant risk factors for infection. Conclusion Decompressive procedures performed later in the day carry a higher risk for postoperative infection. No similar trend was shown for fusion procedures. Our results identify potential modifiable risk factors contributing to infection rates in spinal procedures. Specific risk factors, although not defined in this study, might be related to contamination of the operating room, cross-contamination between health care providers during the course of the day, use of flash sterilization, and mid-day shift changes.

Study design Retrospective, case-control study. Objective The purpose of this study was to determine if thoracolumbar vertebral body collapse, translation, or canal compromise (CC) is associated with injury to the posterior ligamentous complex (PLC) or neurological elements. Summary of background data Radiographical parameters, including loss of vertebral body height (LOVBH), vertebral body translation, local kyphosis (LK), and CC, are often used as indicators of spinal instability. The hypothesis of this study was that LOVBH greater than 50%, LK greater than 20°, translation greater than 3.5 mm, or CC greater than 50% is associated with ligamentous and neurological injury. Methods Retrospective review of prospectively collected spinal cord injury database was performed. Inclusion criteria include consecutive patients with thoracolumbar burst fractures. Exclusion criteria include flexion-distraction injuries and pathological fractures. Computed tomographic scan measurements of the spine were performed by 2 experienced spine surgeons blinded to magnetic resonance imaging results. On magnetic resonance imaging, the supraspinous ligament, interspinous ligament, ligamentum flavum, facet joints, and disc were graded as intact, indeterminate, or disrupted. American Spinal Injury Association (ASIA) score and Frankel Scale score were recorded. Spearman correlation coefficients were calculated to evaluate relationships between vertebral body measurements, ligamentous injury, and neurological injury. Results Forty-six patients were included in the study. Ten patients had kyphosis greater than 20°, 1 patient had kyphosis greater than 30°, and 9 patients had LOVBH greater than 50%. There were 34 patients with vertebral body translation greater than 3.5 mm and 15 patients with CC greater than 50%. Sixteen patients had ligamentous injury. There was a significant correlation between subjacent segment translation greater than 3.5 mm and ligamentous injury (R = 0.323, P = 0.029) and ASIA motor score (R = -0.379, P = 0.009). There was no significant correlation between ligamentous injury or neurological injury and the following threshold parameters: LOVBH greater than 50%, vertebral body kyphosis greater than 20°, caudal or cephalad interspinous widening greater than 7 mm, CC greater than 50%, and sagittal transverse ratio less than 0.48. Conclusion The results of this study indicate that LOVBH greater than 50% and LK greater than 20° are not predictive of PLC injury in thoracolumbar burst fractures. Translation greater than 3.5 mm was associated with PLC injury. The PLC and neural elements should be directly assessed with magnetic resonance imaging if there is clinical concern.

Objective: To study radiographic and clinical outcomes after transforaminal lumbar interbody fusion (TLIF) in order to determine the impact of TLIF on lumbar lordosis, intervertebral height and improvement in clinical outcome measures. Methods: Forty-five patients who had undergone a single-level TLIF procedure for a single-level degenerative condition were retrospectively reviewed and their clinical histories, degree of pre- and post-operative lumbar lordosis, intervertebral height, and cage position recorded. Clinical assessment included use of modified Odom's criteria and a visual analog scale (VAS) for back and leg pain. Results: At 21 months, the patients had gained an average of 3.6° of lumbar lordosis and 4.5 mm disc height. Change in disc height was significantly associated with an anterior cage position while lumbar lordosis was unaffected by cage position. A spondylolisthesis subgroup demonstrated 31% reduction in the magnitude of anterior slip. Less lordosis was associated with worse back and leg pain as assessed by VAS and greater disk heights were associated with higher Odom's criteria scores. Patients with persistent leg pain at final follow-up had less lumbar lordosis and intervertebral height than patients without leg pain. Conclusions: Intervertebral height and lumbar lordosis reconstruction are important for achieving good surgical results; guidance regarding the likely changes in lumbar lordosis and disk height after TLIF is provided by our findings.

Background context Injuries to the thoracolumbar spine may lead to a complex array of clinical syndromes that result from dysfunction of the anterior motor units, lumbosacral nerve roots, and/or spinal cord. Neurologic dysfunction may manifest in the lower extremities as loss of fine and gross motor function, touch, pain, temperature, and proprioceptive and vibratory sense deficits. Two clinical syndromes sometimes associated with these injuries are conus medullaris syndrome (CMS) and cauda equina syndrome (CES). Purpose To review the current management of thoracolumbar spinal cord injuries. Study design Literature review. Methods Index Medicus was used to search the primary literature for articles on thoracolumbar injuries. An emphasis was placed on the current management, controversies, and newer treatment options. Results/conclusions After blunt trauma, these syndromes may reflect a continuum of dysfunction rather than a distinct clinical entity. The transitional anatomy at the thoracolumbar junction, where the conus medullaris is present, makes it less likely that a “pure” CMS or CES syndrome will occur and more likely that a “mixed” injury will. Surgical decompression is the mainstay of treatment for incomplete spinal cord injury (SCI) and incomplete CMS and CES. The value of timing of surgical intervention in the setting of incomplete SCI is unclear at this time. This review summarizes the recent information on epidemiology, pathophysiology, diagnosis, and controversies in the management of thoracolumbar neurologic injury syndromes.

Objective Adjacent segment disease (ASD) requiring treatment or re-operation is a common problem after surgery on the lumbar spine. The hypothesis of this retrospective study was that ASD occurs less often following lumbar spine fusion in patients who undergo percutaneous minimally invasive (MIS) instrumentation than in those in whom open instrumentation is used. Methods A case-control study was performed on consecutive patients who had undergone staged single or two level anterior lumbar interbody fusion for degenerative conditions followed by open or MIS instrumentation from 2002 to 2005 in our institution. ASD was defined as that necessitating additional procedures for new symptoms related to an adjacent lumbar dermatome. Results One hundred and seventeen patients met the inclusion criteria. Of these, 53 had been followed up by chart or medical record review for longer than one year. There were 23 patients in the MIS group and 30 in the open group. Of the 30 patients in the open group, 9 had developed ASD (30%). Of the 23 patients in the MIS group, 7 had developed ASD (30%). This difference is not statistically significant (P = 1.00). Conclusion Contrary to our hypothesis, there was no significant difference in incidence of ASD in patients who had underwent open versus percutaneous instrumentation following anterior lumbar interbody fusion.

Deep venous thrombosis and pulmonary embolism are a major cause of morbidity and mortality after arthroplasty. Chemoprophylaxis has been effective in reducing the incidence of symptomatic deep venous thrombosis, but not of pulmonary embolism, after total hip arthroplasty (THA) and total knee arthroplasty (TKA)1. Rivaroxaban, an orally administered factor Xa inhibitor, has recently been introduced for reducing the incidence of deep vein thrombosis (DVT) and pulmonary embolism (PE) after hip and knee arthroplasty2, 3, 4, 5. Factor Xa catalyzes the conversion of prothrombin to thrombin. Because a single molecule of Xa can generate thousands of thrombin molecules, factor Xa is an excellent drug target6. In many ways, rivaroxaban is an ideal drug, being orally administered, usually requiring no monitoring and having a faster onset of action than warfarin. However, like other effective thromboprophylactic agents, rivaroxaban has been associated with an increased incidence of bleeding from surgical wounds or other sites. Here we present a case of a patient who developed a symptomatic epidural hematoma after postoperative administration of rivaroxaban. The patient was informed that we wanted to submit this case for publication and gave written permission. The purpose of this report was to describe an unanticipated, early complication of a new type of DVT chemoprophylaxis after total knee arthroplasty, thus educating patients and surgeons about the possible risks of chemoprophylaxis. This patient appeared to develop the complication while bridging from a different anticoagulant to rivaroxaban. We now recommend extreme caution re‐using rivaroxaban in the setting of recent spinal anesthesia after arthroplasty.

Background context Kyphoplasty is performed for the treatment of osteoporotic compression fractures. A theoretical advantage of this technique is the reduced risk of embolization of cement. Study design/setting Case report of an incidental finding of cement pulmonary embolization after kyphoplasty of an osteoporotic vertebral compression fracture. Methods/results Here we report a patient who presented with an incidental finding of pulmonary embolization after kyphoplasty and review the relevant literature. Conclusions Patients who present with symptoms of respiratory distress after kyphoplasty should undergo workup for pulmonary embolism. Clinicians may consider routine postoperative chest radiographs after kyphoplasty to screen for embolic disease. Further research is necessary to identify the risk factors and possible long-term sequelae of cement embolization.