Pennings, Jacquelyn S.

Study Design. Retrospective analysis of prospectively collected registry data. Objective. The aim of this study was to compare the performance of 30% reduction to established absolute point-change values for measures of disability and pain in patients undergoing elective cervical spine surgery. Summary of Background Data. Recent studies recommend using a proportional change from baseline instead of an absolute point-change value to define minimum clinically important difference (MCID). Methods. Analyses included 13,179 patients who underwent cervical spine surgery for degenerative disease between April 2013 and February 2018. Participants completed a baseline and 12-month follow-up assessment that included questionnaires to assess disability (Neck Disability Index [NDI]), neck and arm pain (Numeric Rating Scale [NRS-NP/AP], and satisfaction [NASS scale]). Participants were classified as met or not met 30% reduction from baseline in each of the respective measures. The 30% reduction in scores at 12 months was compared to a wide range of established absolute point-change MCID values using receiver-operating characteristic curves, area under the receiver-operating characteristic curve (AUROC), and logistic regression analyses. These analyses were conducted for the entire patient cohort, as well as for subgroups based on baseline severity and surgical approach. Results. Thirty percent reduction in NDI and NRS-NP/AP scores predicted satisfaction with more accuracy than absolute point-change values for the total population and ACDF and posterior fusion procedures (P < 0.05). The largest AUROC differences, in favor of 30% reduction, were found for the lowest disability (ODI 0–20%: 16.8%) and bed-bound disability (ODI 81%–100%: 16.6%) categories. For pain, there was a 1.9% to 11% and 1.6% to 9.6% AUROC difference for no/mild neck and arm pain (NRS 0–4), respectively, in favor of a 30% reduction threshold. Conclusion. A 30% reduction from baseline is a valid method for determining MCID in disability and pain for patients undergoing cervical spine surgery. Level of Evidence: 3

Study Design. Retrospective analysis of prospectively collected registry data. Objective. To develop and validate prediction models for 12-month patient-reported outcomes of disability, pain, and myelopathy in patients undergoing elective cervical spine surgery. Summary of Background Data. Predictive models have the potential to be utilized preoperatively to set expectations, adjust modifiable characteristics, and provide a patient-centered model of care. Methods. This study was conducted using data from the cervical module of the Quality Outcomes Database. The outcomes of interest were disability (Neck Disability Index:), pain (Numeric Rating Scale), and modified Japanese Orthopaedic Association score for myelopathy. Multivariable proportional odds ordinal regression models were developed for patients with cervical radiculopathy and myelopathy. Patient demographic, clinical, and surgical covariates as well as baseline patient-reported outcomes scores were included in all models. The models were internally validated using bootstrap resampling to estimate the likely performance on a new sample of patients. Results. Four thousand nine hundred eighty-eight patients underwent surgery for radiculopathy and 2641 patients for myelopathy. The most important predictor of poor postoperative outcomes at 12-months was the baseline Neck Disability Index score for patients with radiculopathy and modified Japanese Orthopaedic Association score for patients with myelopathy. In addition, symptom duration, workers’ compensation, age, employment, and ambulatory and smoking status had a statistically significant impact on all outcomes (P < 0.001). Clinical and surgical variables contributed very little to predictive models, with posterior approach being associated with higher odds of having worse 12-month outcome scores in both the radiculopathy and myelopathy cohorts (P < 0.001). The full models overall discriminative performance ranged from 0.654 to 0.725. Conclusions. These predictive models provide individualized risk-adjusted estimates of 12-month disability, pain, and myelopathy outcomes for patients undergoing spine surgery for degenerative cervical disease. Predictive models have the potential to be used as a shared decision-making tool for evidence-based preoperative counselling. Level of Evidence: 2.

Abstract BACKGROUND The impact of symptom characteristics on outcomes of spine surgery remains elusive. OBJECTIVE To determine the impact of symptom location, severity, and duration on outcomes following lumbar spine surgery. METHODS We queried the Quality Outcomes Database (QOD) for patients undergoing elective lumbar spine surgery for lumbar degenerative spine disease. Multivariable regression was utilized to determine the impact of preoperative symptom characteristics (location, severity, and duration) on improvement in disability, quality of life, return to work, and patient satisfaction at 1 yr. Relative predictor importance was determined using an importance metric defined as Wald χ 2 penalized by degrees of freedom. RESULTS A total of 22 022 subjects were analyzed. On adjusted analysis, we found patients with predominant leg pain were more likely to be satisfied ( P < .0001), achieve minimum clinically important difference (MCID) in Oswestry Disability Index (ODI) ( P = .002), and return to work ( P = .03) at 1 yr following surgery without significant difference in Euro-QoL-5D (EQ-5D) ( P = .09) [ref = predominant back pain]. Patients with equal leg and back pain were more likely to be satisfied ( P < .0001), but showed no significant difference in achieving MCID ( P = .22) or return to work ( P = .07). Baseline numeric rating scale-leg pain and symptom duration were most important predictors of achieving MCID and change in EQ-5D. Predominant symptom was not found to be an important determinant of return to work. Worker's compensation was found to be most important determinant of satisfaction and return to work. CONCLUSION Predominant symptom location is a significant determinant of functional outcomes following spine surgery. However, pain severity and duration have higher predictive importance. Return to work is more dependent on sociodemographic features as compared to symptom characteristics.

Abstract BACKGROUND Degenerative cervical myelopathy (DCM) is a progressive disease resulting from cervical cord compression. The modified Japanese Orthopaedic Association (mJOA) is commonly used to grade myelopathic symptoms, but its persistent postoperative improvement has not been previously explored. OBJECTIVE To utilize the Quality Outcomes Database (QOD) to evaluate the trajectory of outcomes in those operatively treated for DCM. METHODS This study is a retrospective analysis of prospectively collected data. The QOD was queried for patients undergoing elective surgery for DCM. Patients were divided into mild (≥14), moderate (9-13), or severe (<9) categories for their baseline severity of myelopathic symptoms (mJOA scores). A parsimonious multivariable logistic regression model was fitted with 2 points improvement on mJOA from 3- to 12-mo follow-up as the outcome of interest. RESULTS A total of 2156 patients who underwent elective surgery for DCM and had complete 3- and 12-mo follow-up were included in our analysis. Patients improved significantly from baseline to 3-mo on their mJOA scores, regardless of their baseline mJOA severity. After adjusting for the relevant preoperative characteristics, the baseline mJOA categories had significant impact on outcome of whether a patient keeps improving in mJOA score from 3 to 12 mo postsurgery. Patient with severe mJOA score at baseline had a higher likelihood of improvement in their myelopathic symptoms, compared to patients with mild mJOA score in. CONCLUSION Most patients achieve improvement on a shorter follow-up; however, patients with severe symptoms keep on improving until after a longer follow-up. Preoperative identification of such patients helps the clinician settling realistic expectations for each follow-up timepoint.

Study Design. This study retrospectively analyzes prospectively collected data. Objective. Here, we aim to determine the influence of preoperative and 12-month modified Japanese Orthopedic Association (mJOA) on satisfaction and understand the change in mJOA severity classification after surgical management of degenerative cervical myelopathy (DCM). Summary of Background Data. DCM is a progressive degenerative spine disease resulting from cervical cord compression. The natural progression of DCM is variable; some patients experience periods of stability, while others rapidly deteriorate following disease onset. The mJOA is commonly used to grade and categorize myelopathy symptoms, but its association with postoperative satisfaction has not been previously explored. Methods. The quality and outcomes database (QOD) was queried for patients undergoing elective surgery for DCM. Patients were divided into mild (≥14), moderate (9 to 13), or severe (<9) categories on the mJOA scores. A McNemar–Bowker test was used to assess whether a significant proportion of patients changed mJOA category between preoperative and 12 months postoperative. A multivariable proportional odds ordinal logistic regression model was fitted with 12-month satisfaction as the outcome of interest. Results. We identified 1963 patients who underwent elective surgery for DCM and completed 12-months follow-ups. Comparing mJOA severity level preoperatively and at 12 months revealed that 55% remained in the same category, 37% improved, and 7% moved to a worse category. After adjusting for baseline and surgery-specific variables, the 12-month mJOA category had the highest impact on patient satisfaction (P < 0.001). Conclusion. Patient satisfaction is an indispensable tool for measuring quality of care after spine surgery. In this sample, 12-month mJOA category, regardless of preop mJOA, was significantly correlated with satisfaction. Given these findings, it is important to advise patients of the probability that surgery will change their mJOA severity classification and the changes required to achieve postoperative satisfaction. 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