Preoperative patient-reported outcome score thresholds predict the likelihood of reaching MCID with surgical correction of adult spinal deformity.

BACKGROUND CONTEXT: Preoperative (pre-op) identification of patients likely to achieve a clinically meaningful improvement following surgery for adult spinal deformity (ASD) is critical, especially given the substantial cost and comorbidity associated with surgery. Even though pain is a known indication for surgical ASD correction, we are not aware of established thresholds for baseline pain and function to guide which patients have a higher likelihood of improvement with corrective surgery. PURPOSE: We aimed to establish pre-op patient-reported outcome measure (PROM) thresholds to identify patients likely to improve by at least one minimum clinically important difference (MCID) with surgery for ASD. STUDY DESIGN: This is a retrospective cohort study using prospectively collected data. PATIENT SAMPLE: We reviewed 172 adult patients' charts who underwent corrective surgery for spinal deformity. OUTCOME MEASURES: Included measures were the Visual Analog Scale for pain (VAS), Oswestry Disability Index (ODI), and Scoliosis Research Society-22 (SRS-22). Our primary outcome of interest was improvement by at least one MCID on the ODI and SRS-22 at 2 years after surgery. METHODS: As part of usual care, the VAS, ODI, and SRS-22 were collected pre-op and re-administered at 1, 2, and 5 years after surgery. MCIDs were calculated using a distribution-based method. Determining significant predictors of MCID at two years was accomplished by Firth bias corrected logistic regression models. Significance of predictors was determined by Profile Likelihood Chi-square. We performed a Youden analysis to determine thresholds for the strongest pre-op predictors. RESULTS: At year two, 118 patients (83%) reached MCID for the SRS and 127 (75%) for the ODI. Lower pre-op SRS overall, lower pre-op SRS pain, and higher pre-op SRS function predicted a higher likelihood of reaching MCID on the overall SRS (p < 0.05). Higher pre-op ODI, lower SRS pain and self-image, and higher SRS overall predicted a higher likelihood of reaching MCID on the ODI (p < 0.05). An ODI threshold of 29 predicted reaching MCID with a sensitivity of 0.89 and a specificity of 0.64 (AUC = 0.7813). An SRS threshold of 3.89 predicted reaching MCID with a sensitivity of 0.93 and specificity of 0.68 (AUC = 0.8024). CONCLUSIONS: We identified useful thresholds for ODI and SRS-22 with acceptable predictive ability for improvement with surgery for ASD. Pre-op ODI, SRS, and multiple SRS subscores are predictive of meaningful improvement on the ODI and/or SRS at 2 years following corrective surgery for spinal deformity. These results highlight the usefulness of PROMs in pre-op shared decision-making.

PROMIS Physical Function Correlates with KOOS, JR in Patients with Knee Pain.

Using Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS PF) computerized adaptive test instead of the Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR) could reduce question burden for patients with knee pain. We aimed to prospectively determine the correlation between PROMIS PF and KOOS, JR to assess whether PROMIS PF could be a useful alternative measure for both research and clinical care of patients with knee pain. This was a cross-sectional study of 88 patients. We assessed the correlation between PROMIS PF and KOOS, JR using a Pearson's correlation test. Two multivariable linear regression models were used to determine the amount of variation explained by various patient-level factors. There was a strong correlation between PROMIS PF and KOOS, JR (r = 0.74, p < 0.001). KOOS, JR was an independent predictor of PROMIS PF when controlling for patient-level factors (ß 0.26; p < 0.001). The results of this study support the idea of using PROMIS PF in place of joint-specific measures such as KOOS, JR for clinical care of patients with knee pain. The level of evidence for this study is Level III.