Asher, Anthony L.

Abstract BACKGROUND Given recent differing findings following 2 randomized clinical trials on degenerative lumbar spondylolisthesis (DLS) surgery, there is a need to better define how subsets of patients fare following surgery. OBJECTIVE To investigate the impact of obesity on patient-reported outcomes (PROs) following DLS surgery. METHODS A total of 12 high-enrolling sites were queried, and we found 797 patients undergoing surgery for grade 1 DLS. For univariate comparisons, patients were stratified by BMI ≥ 30 kg/m 2 (obese) and < 30 kg/m 2 (nonobese). Baseline, 3-mo, and 12-mo follow-up parameters were collected. PROs included the North American Spine Society satisfaction questionnaire, numeric rating scale (NRS) back pain, NRS leg pain, Oswestry Disability Index (ODI), and EuroQoL-5D (EQ-5D) Questionnaire. RESULTS We identified 382 obese (47.9%) and 415 nonobese patients (52.1%). At baseline, obese patients had worse NRS back pain, NRS leg pain, ODI, and EQ-5D scores ( P < .001, P = .01, P < .001, and P = .02, respectively). Both cohorts improved significantly for back and leg pain, ODI, and EQ-5D at 12 mo ( P < .001). At 12 mo, similar proportions of obese and nonobese patients responded that surgery met their expectations (62.6% vs 67.4%, P = .24). In multivariate analyses, BMI was independently associated with worse NRS leg pain and EQ-5D at 12 mo ( P = .01 and P < .01, respectively) despite adjusting for baseline differences. CONCLUSION Obesity is associated with inferior leg pain and quality of life—but similar back pain, disability, and satisfaction—12 mo postoperatively. However, obese patients achieve significant improvements in all PRO metrics at 12 mo.

Study Design. This study retrospectively analyzes prospectively collected data. Objective. The primary aim of this study is to present a scheme for patient-reported outcome (PRO)-based, risk-adjusted rankings of spine surgeons and sites that perform elective lumbar surgery, using the Quality and Outcomes Database (QOD). Summary of Background Data. There is currently no means of determining which spine surgeons or centers are positive or negative outliers with respect to PROs for elective lumbar surgery. This is a critical gap as we move toward a value-based model of health care in which providers assume more accountability for the effectiveness of their treatments. Methods. Random effects regression models were fit for the following outcomes, with QOD site as a fixed effect but surgeon ID as a random effect: Oswestry Disability Index, EQ-5D, back pain and leg pain, and satisfaction. Hierarchical Bayesian models were also fit for each outcome, with QOD site as a random effect and surgeon as a nested random effect. Results. Our study cohort consists of 8834 patients who underwent surgery by 124 QOD surgeons, for the degenerative lumbar diseases. Nonoverlapping Bayesian credible intervals demonstrate that the variance attributed to QOD site was greater than the nested variance attributed to surgeon ID for the included PROs. Conclusion. This study presents a novel strategy for the risk-adjusted, PRO-based ranking of spine surgeons and practices. This can help identify positive and negative outliers, thereby forming the basis for large-scale quality improvement. Assuming adequate coverage of baseline risk adjustment, the choice of surgeon matters when considering PROs after lumbar surgery; however, the choice of site appears to matter more. Level of Evidence: 3

Study Design. This study retrospectively analyzes prospectively collected data. Objective. Here we aim to develop predictive models for 3-month medical and surgical readmission after elective lumbar surgery, based on a multi-institutional, national spine registry. Summary of Background Data. Unplanned readmissions place considerable stress on payers, hospitals, and patients. Medicare data reveals a 30-day readmission rate of 7.8% for lumbar-decompressions and 13.0% for lumbar-fusions, and hospitals are now being penalized for excessive 30-day readmission rates by virtue of the Hospital Readmissions Reduction Program. Methods. The Quality and Outcomes Database (QOD) was queried for patients undergoing elective lumbar surgery for degenerative diseases. The QOD prospectively captures 3-month readmissions through electronic medical record (EMR) review and self-reported outcome questionnaires. Distinct multivariable logistic regression models were fitted for surgery-related and medical readmissions adjusting for patient and surgery-specific variables. Results. Of the total 33,674 patients included in this study 2079 (6.15%) reported at least one readmission during the 90-day postoperative period. The odds of medical readmission were significantly higher for older patients, males versus females, African Americans versus Caucasion, those with higher American Society of Anesthesiologists (ASA) grade, diabetes, coronary artery disease, higher numbers of involved levels, anterior only or anterior–posterior versus posterior approach; also, for patients who were unemployed compared with employed patients and those with high baseline Oswestry Disability Index (ODI). The odds of surgery-related readmission were significantly greater for patients with a higher body mass index (BMI), a higher ASA grade, female versus male, and African Americans versus Caucasians; also, for patients with severe depression, more involved spinal levels, anterior-only surgical approaches and higher baseline ODI scores. Conclusion. In this study we present internally validated predictive models for medical and surgical readmission after elective lumbar spine surgery. These findings set the stage for targeted interventions with a potential to reduce unnecessary readmissions, and also suggest that medical and surgical readmissions be treated as distinct clinical events. Level of Evidence: 3

Abstract BACKGROUND Emergency department (ED) overuse is a costly and often neglected source of postdischarge resource utilization after spine surgery. Failing to investigate drivers of ED visits represents a missed opportunity to improve the value of care in spine patients. OBJECTIVE To identify the prevalence, drivers, and timing of ED visits following elective spine surgery. METHODS Patients undergoing elective spine surgery for degenerative disease at a major medical center were enrolled in a prospective longitudinal registry. Patient and surgery characteristics, and patient-reported outcomes were recorded at baseline and 3 mo after surgery, along with self-reported 90-d ED visits. A multivariable regression model was used to identify independent factors associated with 90-d ED visits. For a sample of patients presenting to our institution's ED, charts were reviewed to identify the reason and time to ED postdischarge. RESULTS Of 2762 patients, we found a 90-d ED visit rate of 9.4%. One-third of patients presented to our institution's ED and of these, 70% presented due to pain or medical concerns at 9 and 7 d postdischarge, respectively, with 60% presenting outside normal clinic hours. Independent risk factors for 90-d ED visits included younger age, preoperative opioid use, chronic obstructive pulmonary disorder, and more vertebral levels involved. CONCLUSION Nearly 10% of elective spine patients had 90-d ED visits not requiring readmission. Pain and medical concerns accounted for 70% of visits at our center, occurring within 10 d of discharge. This study provides the clinical details and a timeline necessary to guide individualized interventions to prevent unnecessary, costly ED visits after spine surgery.

Abstract BACKGROUND Reducing length of stay (LOS) in a safe manner has the potential to save significant costs for the care of patients undergoing elective lumbar spine surgery. Due to the relative absence on weekends of staff required for discharging patients to rehabilitation or nursing facilities, we hypothesize that patients undergoing lumbar surgery later in the week have a longer LOS than their counterparts. OBJECTIVE To analyze the effect of day of the week for lumbar surgery on LOS. METHODS Patients undergoing surgery for lumbar degenerative disease were prospectively enrolled in the multicenter quality and outcomes database registry. A multivariable proportional odds regression model was built with LOS as the outcome of interest and patient and surgical variables as covariates. RESULTS A total of 11 897 patients were analyzed. Among those discharged home, the regression analysis demonstrated significantly higher odds of longer LOS for patients undergoing surgery on Friday as compared to Monday ( P < .001). Among those discharged to a facility, there were significantly higher odds of longer LOS for patients undergoing surgery on Wednesday ( P < .001), Thursday ( P < .001), and Friday ( P = .002) as compared to Monday. CONCLUSION The findings of this study suggest that lumbar patients undergoing fusions and those discharged to a facility have longer LOS when surgery is later in the week. Scheduling these patients for surgery earlier in the week and ensuring adequate resources for patient disposition on weekends may lead to LOS reduction and cost savings for hospitals, payers, and patients alike.

Abstract Patients who undergo surgical resection of brain metastases are at significant risk of cavity local recurrence without additional radiation therapy. Postoperative stereotactic radiosurgery (SRS) is a method of focal treatment to the cavity to maximize local control while minimizing the risk of neurocognitive detriment associated with whole brain radiation therapy. Recently published randomized trials have demonstrated the benefit of postoperative SRS in terms of cavity tumor control and preserving neurocognition. However, there are several potential drawbacks with postoperative SRS including a possible increase in symptomatic radiation necrosis because of the need for cavity margin expansion due to target delineation uncertainty, the variable postoperative clinical course and potential delay in administering postoperative SRS, and the theoretical risk of tumor spillage into cerebrospinal fluid at the time of surgery. Preoperative SRS is an alternative paradigm wherein SRS is delivered prior to surgical resection, which may effectively address some of these potential drawbacks. The goal of this review is to examine the rationale, technique, outcomes, evidence, and future directions for the use of SRS as an adjunct to surgical resection. This can be delivered as either preoperative or postoperative SRS with potential advantages and disadvantages to both approaches that will be discussed.

Abstract BACKGROUND The choice of anterior vs posterior approach for degenerative cervical myelopathy that spans multiple segments remains controversial. OBJECTIVE To compare the outcomes following the 2 approaches using multicenter prospectively collected data. METHODS Quality Outcomes Database (QOD) for patients undergoing surgery for 3 to 5 level degenerative cervical myelopathy was analyzed. The anterior group (anterior cervical discectomy [ACDF] or corpectomy [ACCF] with fusion) was compared with posterior cervical fusion. Outcomes included: patient reported outcomes (PROs): neck disability index (NDI), numeric rating scale (NRS) of neck pain and arm pain, EQ-5D, modified Japanese Orthopedic Association score for myelopathy (mJOA), and NASS satisfaction questionnaire; hospital length of stay (LOS), 90-d readmission, and return to work (RTW). Multivariable regression models were fitted for outcomes. RESULTS Of total 245 patients analyzed, 163 patients underwent anterior surgery (ACDF-116, ACCF-47) and 82 underwent posterior surgery. Patients undergoing an anterior approach had lower odds of having higher LOS ( P < .001, odds ratio 0.16, 95% confidence interval 0.08-0.30). The 12-mo NDI, EQ-5D, NRS, mJOA, and satisfaction scores as well as 90-d readmission and RTW did not differ significantly between anterior and posterior groups. CONCLUSION Patients undergoing anterior approaches for 3 to 5 level degenerative cervical myelopathy had shorter hospital LOS compared to those undergoing posterior decompression and fusion. Also, patients in both groups exhibited similar long-term PROs, readmission, and RTW rates. Further investigations are needed to compare the differences in longer term reoperation rates and functional outcomes before the clinical superiority of one approach over the other can be established.

OBJECTIVE Patient-reported outcomes (PROs) play a pivotal role in defining the value of surgical interventions for spinal disease. The concept of minimum clinically important difference (MCID) is considered the new standard for determining the effectiveness of a given treatment and describing patient satisfaction in response to that treatment. The purpose of this study was to determine the MCID associated with surgical treatment for degenerative lumbar spondylolisthesis. METHODS The authors queried the Quality Outcomes Database registry from July 2014 through December 2015 for patients who underwent posterior lumbar surgery for grade I degenerative spondylolisthesis. Recorded PROs included scores on the Oswestry Disability Index (ODI), EQ-5D, and numeric rating scale (NRS) for leg pain (NRS-LP) and back pain (NRS-BP). Anchor-based (using the North American Spine Society satisfaction scale) and distribution-based (half a standard deviation, small Cohen’s effect size, standard error of measurement, and minimum detectable change [MDC]) methods were used to calculate the MCID for each PRO. RESULTS A total of 441 patients (80 who underwent laminectomies alone and 361 who underwent fusion procedures) from 11 participating sites were included in the analysis. The changes in functional outcome scores between baseline and the 1-year postoperative evaluation were as follows: 23.5 ± 17.4 points for ODI, 0.24 ± 0.23 for EQ-5D, 4.1 ± 3.5 for NRS-LP, and 3.7 ± 3.2 for NRS-BP. The different calculation methods generated a range of MCID values for each PRO: 3.3–26.5 points for ODI, 0.04–0.3 points for EQ-5D, 0.6–4.5 points for NRS-LP, and 0.5–4.2 points for NRS-BP. The MDC approach appeared to be the most appropriate for calculating MCID because it provided a threshold greater than the measurement error and was closest to the average change difference between the satisfied and not-satisfied patients. On subgroup analysis, the MCID thresholds for laminectomy-alone patients were comparable to those for the patients who underwent arthrodesis as well as for the entire cohort. CONCLUSIONS The MCID for PROs was highly variable depending on the calculation technique. The MDC seems to be a statistically and clinically sound method for defining the appropriate MCID value for patients with grade I degenerative lumbar spondylolisthesis. Based on this method, the MCID values are 14.3 points for ODI, 0.2 points for EQ-5D, 1.7 points for NRS-LP, and 1.6 points for NRS-BP.

OBJECTIVE The American Association of Neurological Surgeons launched the Quality Outcomes Database (QOD), a prospective longitudinal registry that includes demographic, clinical, and patient-reported outcome (PRO) data, to measure the safety and quality of neurosurgical procedures, including spinal surgery. Differing results from recent randomized controlled trials have established a need to clarify the groups that would most benefit from surgery for degenerative lumbar spondylolisthesis. In the present study, the authors compared patients who were the most and the least satisfied following surgery for degenerative lumbar spondylolisthesis. METHODS This was a retrospective analysis of a prospective, national longitudinal registry including patients who had undergone surgery for grade 1 degenerative lumbar spondylolisthesis. The most and least satisfied patients were identified based on an answer of “1” and “4,” respectively, on the North American Spine Society (NASS) Satisfaction Questionnaire 12 months postoperatively. Baseline demographics, clinical variables, surgical parameters, and outcomes were collected. Patient-reported outcome measures, including the Numeric Rating Scale (NRS) for back pain, NRS for leg pain, Oswestry Disability Index (ODI), and EQ-5D (the EuroQol health survey), were administered at baseline and 3 and 12 months after treatment. RESULTS Four hundred seventy-seven patients underwent surgery for grade 1 degenerative lumbar spondylolisthesis in the period from July 2014 through December 2015. Two hundred fifty-five patients (53.5%) were the most satisfied and 26 (5.5%) were the least satisfied. Compared with the most satisfied patients, the least satisfied ones more often had coronary artery disease (CAD; 26.9% vs 12.2%, p = 0.04) and had higher body mass indices (32.9 ± 6.5 vs 30.0 ± 6.0 kg/m 2 , p = 0.02). In the multivariate analysis, female sex (OR 2.9, p = 0.02) was associated with the most satisfaction. Notably, the American Society of Anesthesiologists (ASA) class, smoking, psychiatric comorbidity, and employment status were not significantly associated with satisfaction. Although there were no significant differences at baseline, the most satisfied patients had significantly lower NRS back and leg pain and ODI scores and a greater EQ-5D score at 3 and 12 months postoperatively (p < 0.001 for all). CONCLUSIONS This study revealed that some patient factors differ between those who report the most and those who report the least satisfaction after surgery for degenerative lumbar spondylolisthesis. Patients reporting the least satisfaction tended to have CAD or were obese. Female sex was associated with the most satisfaction when adjusting for potential covariates. These findings highlight several key factors that could aid in setting expectations for outcomes following surgery for degenerative lumbar spondylolisthesis.