Burden of Sciatica on US Medicare Recipients.

OBJECTIVE: This study evaluates the disease burden of sciatica on the US Medicare cohort. BACKGROUND DATA: Sciatica is a common disability that has important physical, mental, and economic effects. The Medicare Health Outcomes Survey (HOS) is a demographic and outcomes survey used to monitor the performance of Medicare Advantage health plans in the United States. The HOS includes data on demographics, chronic medical conditions, and patient-reported outcomes. METHODS: Medicare HOS data for cohorts from 2007 to 2013 were obtained. Patients were placed into two categories based on the survey results: with or without a history of sciatica. Baseline demographics, chronic medical conditions, and physical health symptoms were aggregated. In addition, average VR-12 physical component summary and mental component summary scores were calculated for each group at baseline and at 2-year follow-up. A Fisher exact test was used to assess significance for categorical variables, and a t-test was used for continuous variables. VR-12 changes as small as 1 to 2 units have been found to be clinically and socially relevant. RESULTS: The baseline cohort data of 1,000,952 patients yielded 250,869 patients (25%) who reported the diagnosis of sciatica, compared with 750,083 patients (75%) without sciatica. Patients with a history of sciatica tended to be younger, less educated, and notably with more medical comorbidities. Physical component summary outcomes were approximately 8 units lower in the sciatica group at baseline and 7 units lower at 2-year follow-up. Mental component summary outcomes were 6 units lower in the sciatica group at baseline and 5 units lower at 2-year follow-up. CONCLUSION: A large percentage of the US Medicare cohort suffers from symptomatic sciatica. Our study identified a 25% prevalence in the Medicare cohort. In addition, sciatica is associated with an increased incidence of comorbid medical conditions and poor health-related quality of life. LEVEL OF EVIDENCE: Level III STUDY DESIGN:: Observational-Cohort Study.

Can the American College of Surgeons Risk Calculator Predict 30-day Complications After Spine Surgery?

MINI: It is unclear whether the ACS NSQIP Surgical Risk Calculator can predict 30-day complications after lumbar and cervical spinal fusions. This study shows that the Risk Calculator is only of marginal benefit in predicting outcomes in cervical fusion and unlikely to be of benefit in lumbar fusions. STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim of this study was to assess the American College of Surgeons National Surgery Quality Improvement Program (ACS NSQIP) Risk Calculator's ability to predict 30-day complications after spine surgery. SUMMARY OF BACKGROUND DATA: Surgical risk calculators may identify patients at increased risk for complications, improve outcomes, enhance the informed consent process, and help modify risk factors. The ACS NSQIP Risk Calculator was developed from a cohort of >1.4 million patients, using 2805 unique CPT codes. It uses 21 patient predictors and the planned procedure to predict the risk of 12 different outcomes within 30 days following surgery. METHODS: A retrospective chart review was performed on patients who underwent primary lumbar and cervical fusions with at least 30-day postoperative follow-up between 2009 and 2015 at a single-institution. Descriptive statistics were calculated for the overall sample, anterior versus posterior fusion (cervical only), and single versus multilevel fusion. Logistic regression models were fit with actual complication occurrence as the dependent variable in each model and ACS estimated risk as the independent variable. The c-statistic was used as the measure of concordance for each model. Receiver-operating charateristic curves depicted the predictive ability of the estimated risks. Acceptable concordance was set at c >0.80. RESULTS: A total of 237 lumbar and 404 cervical patients were included in the study. The Risk Calculator risk estimates significantly predicted (P < 0.001) "any complication" and "discharge to skilled nursing facility" among the cervical cohort and demonstrated no significant outcome prediction the lumbar cohort. CONCLUSION: The ACS Risk-Calculator accurately predicted complications in the categories of "any complication" and "discharge to skilled nursing facility" for our cervical cohort and failed to demonstrate benefit for our lumbar cohort. Although the ACS Risk-Calculator may be useful in general surgery, our findings demonstrate that it does not necessarily provide accurate information for patients undergoing spinal surgery. LEVEL OF EVIDENCE: 3.

Retrospective cohort study. The aim of this study was to assess the American College of Surgeons National Surgery Quality Improvement Program (ACS NSQIP) Risk Calculator's ability to predict 30-day complications after spine surgery. Surgical risk calculators may identify patients at increased risk for complications, improve outcomes, enhance the informed consent process, and help modify risk factors. The ACS NSQIP Risk Calculator was developed from a cohort of >1.4 million patients, using 2805 unique CPT codes. It uses 21 patient predictors and the planned procedure to predict the risk of 12 different outcomes within 30 days following surgery. A retrospective chart review was performed on patients who underwent primary lumbar and cervical fusions with at least 30-day postoperative follow-up between 2009 and 2015 at a single-institution. Descriptive statistics were calculated for the overall sample, anterior versus posterior fusion (cervical only), and single versus multilevel fusion. Logistic regression models were fit with actual complication occurrence as the dependent variable in each model and ACS estimated risk as the independent variable. The c-statistic was used as the measure of concordance for each model. Receiver-operating charateristic curves depicted the predictive ability of the estimated risks. Acceptable concordance was set at c >0.80. A total of 237 lumbar and 404 cervical patients were included in the study. The Risk Calculator risk estimates significantly predicted (P < 0.001) "any complication" and "discharge to skilled nursing facility" among the cervical cohort and demonstrated no significant outcome prediction the lumbar cohort. The ACS Risk-Calculator accurately predicted complications in the categories of "any complication" and "discharge to skilled nursing facility" for our cervical cohort and failed to demonstrate benefit for our lumbar cohort. Although the ACS Risk-Calculator may be useful in general surgery, our findings demonstrate that it does not necessarily provide accurate information for patients undergoing spinal surgery. Level of Evidence: 3.

Spinal Reconstruction Techniques for Traumatic Spinal Injuries: A Systematic Review of Biomechanical Studies.

STUDY DESIGN: Systematic literature review. OBJECTIVES: Many studies have provided evidence that short-segment posterior fixation (SSPF-1 level above and 1 below) with screws at the fracture level (SFL) are enough to achieve stability in some injury patterns, such as burst fractures, avoiding the need for circumferential reconstruction and long-segment instrumented fusion (LSIF-at least 2 levels above and 2 below). Given the potential benefits of avoiding unnecessary fusion in mobile healthy spinal segments, we performed a systematic review of biomechanical studies comparing different spinal reconstruction techniques for fractures of the thoracolumbar spine. METHODS: A systematic literature review was performed in the PubMed and OVID databases of biomechanical studies comparing biomechanical differences between techniques of spine reconstructions. RESULTS: Eight studies were included and evaluated. Five of 6 studies reported stiffness improvement with SSPF and SFL, even comparable to circumferential fusion for a burst fracture. Two studies reported that LSPF has higher stiffness and restricts range of motion better than SSPF, but inclusion of screws in the fracture level is similar to LSPF (1 study). Finally, although SSPF is less stiff than anterior reconstruction, adding a SFL in SSPF results in similar stiffness than circumferential fusion for unstable burst fractures. CONCLUSIONS: Biomechanical studies analyzed generally suggested that SFL in SSPF may improve construction stiffness, and can even be compared with long-segment fixation or circumferential reconstruction in some scenarios. This construct option may be used to enhance stiffness in selected injury patterns, avoiding the needs of an additional anterior approach.

Biomechanical Analysis of Stand-alone Lateral Lumbar Interbody Fusion for Lumbar Adjacent Segment Disease.

Study design Biomechanical cadaveric study  Objective To compare biomechanical properties of a single stand-alone interbody fusion and a single-level pedicle screw construct above a previous lumbar pedicle fusion. Summary of background data Adjacent segment disease (ASD) is spondylosis of adjacent vertebral segments after previous spinal fusion. Despite the consensus that ASD is clinically significant, the surgical treatment of ASD is controversial. Methods Lateral lumbar interbody fusion (LLIF) and posterior spinal fusion (PSF) with pedicle screws were analyzed within a validated cadaveric lumbar fusion model. L3-4 vertebral segment motion was analyzed within the following simulations: without implants (intact), L3-4 LLIF-only, L3-4 LLIF with previous L4-S1 PSF, L3-4 PSF with previous L4-S1 PSF, and L4-S1 PSF alone. L3-4 motion values were measured during flexion/extension with and without axial load, side bending, and axial rotation. Results L3-4 motion in the intact model was found to be 4.7 ± 1.2 degrees. L3-4 LLIF-only decreased motion to 1.9 ± 1.1 degrees. L3-4 LLIF with previous L4-S1 fusion demonstrated less motion in all planes with and without loading (p < 0.05) compared to an intact spine. However, L3-4 motion with flexion/extension and lateral bending was noted to be greater compared to the L3-S1 construct (p < 0.5). The L3-S1 PSF construct decreased motion to less than 1° in all planes of motion with or without loading (p < 0.05). The L3-4 PSF with previous L4-S1 PSF constructs decreased the flexion/extension motion by 92.4% compared to the intact spine, whereas the L3-4 LLIF with previous L4-S1 PSF constructs decreased motion by 61.2%. Conclusions Stand-alone LLIF above a previous posterolateral fusion significantly decreases motion at the adjacent segment, demonstrating its utility in treating ASD without necessitating revision. The stand-alone LLIF is a biomechanically sound option in the treatment of ASD and is advantageous in patient populations who may benefit from less invasive surgical options.

The Effectiveness of Bioskills Training for Simulated Lumbar Pedicle Screw Placement.

STUDY DESIGN: Prospective randomized study. OBJECTIVES: To define the impact of an inexpensive, user-friendly, and reproducible lumbar pedicle screw instrumentation bioskills training module and evaluation protocol. METHODS: Participants were randomized to control (n = 9) or intervention (n = 10) groups controlling for level of experience (medical students, junior resident, or senior resident). The intervention group underwent a 20-minute bioskills training module while the control group spent the same time with self-directed study. Pre- and posttest performance was self-reported (Physician Performance Diagnostic Inventory Scale [PPDIS]). Objective outcome scores were obtained from a blinded fellowship-trained attending orthopedic spine surgeon using Objective Structured Assessment of Technical Skills (OSATS) and Objective Pedicle Instrumentation Score metrics. In addition, identification of pedicle breach and breach anatomic location was measured pre- and posttest in lumbar spine models. RESULTS: The intervention group showed a 30.8% improvement in PPDIS scores, compared with 13.4% for the control group (P = .01). The intervention group demonstrated statistically significant 66% decrease in breaches (P = .001) compared with 28% decrease in the control group (P = .06). Breach identification demonstrated no change in accuracy of the control group (incorrect identification from 32.2% pre- to posttest 35%; P = .71), whereas the intervention group's improvement was statistically significant (42% pre- to posttest 36.5%; P = .0047). CONCLUSIONS: We conclude that a concise lumbar pedicle screw instrumentation bioskills training session can be a useful educational tool to augment clinical education.