Comparison of PROMIS scores after total hip and total ankle arthroplasty : a propensity score-matched study.

Aims: This study evaluated joint-specific and generic patient-reported outcome measures (PROMs) after total hip arthroplasty (THA) and total ankle arthroplasty (TAA) in matched cohorts, while evaluating implant survivorship and 90-day hospital use.

Methods: Primary THA and TAA patients from 1 January 2015 to 1 January 2023 with minimum one-year follow-up were retrospectively reviewed. After applying exclusion criteria, 2,092 THAs and 478 TAAs were analyzed. Demographics, pre- and postoperative PROMs, revision surgeries, emergency department visits, and readmissions were collected. THA and TAA patients were then propensity score matched at a 2:1 ratio for age, sex, race, BMI, American Society of Anesthesiologists classification, and comorbidities, resulting in a final cohort of 844 THAs and 455 TAAs for comparison.

Results: Median preoperative Patient-Reported Outcomes Measurement Information System (PROMIS) pain interference (PI) scores between THA and TAA were calculated (66.0 (IQR 62.0 to 70.0) vs 65.0 (IQR 62.0 to 70.0); p = 0.276), and both showed improvement at six weeks. However, THA patients exhibited lower median PROMIS PI scores at one year (53.0 vs 54.0; p = 0.009), as well as a greater median decrease in PROMIS PI from preoperative to one year (-13.0 (IQR -20.0 to -8.0) vs -12.0 (IQR -18.0 to -7.0); p = 0.023). Median preoperative PROMIS physical function (PF) was worse in THA patients (36.0 (IQR 32.0 to 40.0) vs 37.0 (IQR 33.0 to 40.0); p = 0.031), but showed greater median improvement compared to TAA patients at both six weeks (7.0 (IQR 3.0 to 12.0) vs 3.0 (IQR -2.0 to 9.0); p < 0.001) and one year (11.0 (IQR 6.0 to 17.0) vs 8.0 (IQR 4.5 to 13.0); p < 0.001). Preoperative PROMIS depression scores were similar and improved similarly in both groups. Joint-specific PROMs improved in both cohorts.

Conclusion: Patients undergoing THA or TAA experienced improvements in joint-specific PROMs postoperatively which translated to improved generic PROMs across both joints. Generic PROMs can be a useful tool to compare outcomes in THA and TAA. Results suggest that higher functional scores may be achieved sooner in THA.