53. Comparison of generic vs spine-specific pain surveys administered before surgery and fulfillment of expectations measured after surgery for lumbar degenerative spondylolisthesis

BACKGROUND CONTEXT Generic and spine-specific surveys are used before surgery for lumbar degenerative spondylolisthesis (LDS) to measure pain. While both types of surveys can discern various aspects of pain, such as pain intensity and pain-associated disability, their ability to capture how pain impacts other outcomes, such as fulfillment of expectations, is not known. PURPOSE To determine which pain surveys are most closely associated with fulfillment of expectations after surgery for LDS. STUDY DESIGN/SETTING Prospective 2-year longitudinal study, tertiary spine center. PATIENT SAMPLE A total of 146 patients undergoing surgery for LDS. OUTCOME MEASURES HSS Lumbar Spine Surgery Expectations Survey. METHODS Patients were interviewed several days before surgery with the valid 20-item Expectations Survey addressing symptoms, physical function, and psychological well-being. Patients rated how much improvement they expected for each item with response options of complete to no improvement. To measure pain, patients completed back-specific measures of global pain with a numeric rating scale (0-10) and the modified Oswestry Disability index (ODI) (0-100), and generic PROMIS measures of Pain Intensity and Pain Interference with computer adapted tests (T scores 50). Medical records were reviewed for surgeon-reported pain on flexion/extension and surgical complexity according to the Invasiveness Index (max 10 points/vertebral level). Two-year postop patients again completed the Expectations Survey rating how much improvement they actually received. A proportion of expectations fulfilled was calculated as total improvement received divided by total improvement expected (range 0 (no improvement), 1 (improved as expected), >1 (improved more than expected). In multivariable linear regression analyses controlling for complexity, the proportion was the dependent variable and various pain measures were independent variables, expressed as estimates with desired 95% confidence intervals (CI) not to cross 0. RESULTS Mean age was 68, 61% were women, 82% had LDS at only one level (69% L45), mean pelvic incidence was 61° (30-84), mean pelvic incidence minus lumbar lordosis was 10° ((-16)-50), and the median surgical complexity was 7 (1-22). With respect to pain, 60% of patients had pain with extension, 25% with flexion. The median global back pain was 6 (0-10), and mean values were: ODI 50 (6-88), PROMIS Intensity 55 (31-72), and PROMIS Interference 63 (3-100). The mean time to follow-up was 2.1 years. The mean Expectations Survey proportion of expectations fulfilled was .99 (0-3.53); 42% of patients had low, 21% had equivalent, and 36% had high proportions (ie, greater expectations fulfilled). Controlling for surgical complexity, higher proportions were associated with less ODI pain (1.1, CI 0.5-1.6, p=.0001), less global back pain (4.5, CI 1.6-7.3, p=002) and, to lesser extents, less generic PROMIS Pain Intensity (1.5, 0.3-2.6, p=.01) and Pain Interference (0.8, -0.1-1.6, p=.08). There were no associations between surgeon-reported pain on extension/flexion and proportions of expectations fulfilled (p>.10). CONCLUSIONS Compared to generic pain surveys, preop pain measured by spine-specific pain surveys were more closely associated with the outcome of fulfillment of expectations. Whether generic pain surveys, such as PROMIS, are sufficiently sensitive to explain other outcomes of LDS needs to be assessed further. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.