Defining the Patient Acceptable Symptom State (PASS) for PROMIS After Hallux Valgus Correction Surgery

Abstract

Introduction/Purpose: Surgical interventions to correct hallux valgus have been shown to improve patient reported outcomes (PROs); however, many of these instruments do not measure a patient’s subjective outcome experience. The patient acceptable symptom state (PASS) is defined as the symptom threshold that a patient must reach to be satisfied with the outcome of their surgery. PASS thresholds have been defined for hallux valgus correction using American Orthopaedic Foot & Ankle Society (AOFAS) scores; however, no studies have used a validated PRO metric. This is the first study that aims to establish PASS thresholds for Patient-Reported Outcome Measurement Information System (PROMIS) scores in patients following operative intervention for hallux valgus. Methods: A retrospective review of prospectively collected data within an institutional registry was performed. We identified 291 patients treated for hallux valgus with or without second hammertoe correction between February 2019 and March 2021 with at least 2-year post-operative PROMIS scores. Chart review was performed to obtain demographic information and to confirm the surgical procedures completed. Two-years post-operatively, patients answered two PASS anchor questions (Satisfaction, Delighted-Terrible scale) with Likert-scale responses, which was collected along with pre-operative and 2-year post-operative PROMIS scores via the registry. After patient’s answers to the Satisfaction and Delighted-Terrible scales were recategorized into binary responses; PASS thresholds were determined using the maximum Youden Index and a 95% confidence interval was quantified using 2000 bootstrapped iterations. Differences in patient and surgical characteristics between patients who met or did not meet the PASS threshold were compared using independent samples t-test and Pearson chi square. Results: There was excellent association between PASS thresholds and the PROMIS domains of Physical Function (50.3, AUC=0.86) and Pain Interference (51.5, AUC=0.86). Overall, 204/291 and 205/291 patients met the threshold for Physical Function (PF) and Pain Interference (PI), respectively. For both PROMIS domains, a lower BMI was associated with a higher likelihood of meeting the PASS threshold (p=0.002 for PF, p=0.032 for PI). For the PF domain, Lapidus patients were more likely to meet the PASS threshold (p=0.05), and patients with first MTP fusion were less likely to meet the PASS threshold (p=0.004). Meeting the PASS threshold wasn’t impacted by the concomitant correction of a second hammertoe. Lastly, patients with a higher pre-operative PF score had a greater chance of meeting the PASS threshold (p < 0.001). Conclusion: This is the first study to define a PASS threshold for hallux valgus correction using PROMIS scores, a validated outcomes measure. Pre-operative PROMIS scores, patient BMI, and the type of procedure performed impacted a patient’s likelihood of meeting the PASS threshold. These results may be helpful in counseling and educating patients on their chances of obtaining a satisfactory result following hallux valgus correction.