PROMIS Patient Reported Pain Outcomes Compared With Numerical Pain Score Before and After Ankle Surgery

CATEGORY: Patient Reported Outcomes INTRODUCTION/PURPOSE: Patient reported outcomes (PRO) are important for measuring clinical changes after surgical intervention. This study compares PROMIS pain intensity, PROMIS pain interference, and a zero-to-ten numerical pain score (NPS) before and after three common ankle surgeries to test the hypothesis that pain improvement is measurable by each scale. In addition, the effects size (ES) of each scale is compared to help determine which scale may provide the most power to detect an improvement in pain. METHODS: PRO scores were routinely collected during clinic visits between 2015 and 2018. Over 175 patients who had undergone total ankle replacement, subtalar fusion, or lateral ankle ligament stabilization were identified in the electronic health record using the surgical billing codes for these procedures. The most recent preoperative and postoperative PROs for these patients were compared by Mann-Whitney U, and effect size was calculated using Cohen’s d. RESULTS: For total ankle replacement, NPS, pain intensity, and pain interference all improved (p<0.05) with ES 1.29, 0.95, and 0.63 respectively. For subtalar fusion, NPS, and pain interference improved (p<0.05) with ES 0.86 and 0.54; pain intensity (p=0.21) was unchanged with ES 0.30. For lateral ankle ligament stabilization, NPS, and pain interference improved (p<0.05) with ES 0.49 and 0.59; pain intensity (p=0.49) was unchanged with ES 0.19. CONCLUSION: While both NPS and PROMIS pain interference consistently demonstrated improvements after common ankle surgeries, NPS is preferable given its single question format and greater effect size in two of the three procedures studies. PROMIS pain intensity did not routinely measure changes in our surgical population questioning its utility.