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

Introduction/Purpose: In an ever-changing healthcare landscape, patient-reported outcomes (PROs) are becoming more important for reimbursement and evaluating the success of surgical procedures. Unfortunately, it is unclear which PROs correlate best with clinical improvement. The patient acceptable symptom state (PASS) asks the patient whether or not their outcome is acceptable at a particular post-operative time point. Recently, the use of this metric has gained traction within the foot and ankle literature. To our knowledge, this is the first study that aims to establish PASS thresholds for Patient-Reported Outcome Measurement Information System (PROMIS) scores in patients who underwent operative intervention for hallux rigidus. Methods: A retrospective review of prospectively collected data within an institutional registry was performed. We identified 174 patients treated for hallux rigidus 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 that were 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. Statistical significance was established at an alpha of 0.05. Results: There was excellent association between PASS thresholds and the PROMIS domains of Physical Function (48.6, AUC=0.82) and Pain Interference (52.1, AUC =0.86). Overall, 125/174 (71.8%) and 105/174 (60.3%) patients met the threshold for Physical Function (PF) and Pain Interference (PI), respectively. For the PF and PI domains, age, BMI, method of cheilectomy and use of Akin/Moberg osteotomy did not impact a patient’s likelihood of meeting the PASS threshold. For the PF domain and the PI domain stratified by the Delighted-Terrible scale, women were more likely to meet the PASS threshold than men (63.2% vs. 36.8%, p = 0.057 and 73% vs. 45%, p =0.023, respectively). Lastly, patients with a higher pre-operative PF score had a higher chance of meeting the PASS threshold (p < 0.001). Conclusion: Following operative intervention to treat hallux rigidus, pre-operative PROMIS scores were strongly associated with a patient’s likelihood of meeting the PASS threshold. After surgical intervention for hallux rigidus, less than 75% of the patients felt their outcome was acceptable; however, the PASS threshold for PF was lower than population average, so it may not be necessary for patients to reach normal physical function levels post-operatively in order to have an acceptable outcome.