Association Between Early Joint Awareness and Falls After Total Hip Arthroplasty

Background The Forgotten Joint Score-12 (FJS-12) is a patient-reported outcome measure of joint awareness after total hip arthroplasty (THA). Falls after THA remain clinically important. However, longitudinal evidence regarding the associations among early FJS-12, subsequent falls, and later recovery of joint unawareness remains limited. Methods This retrospective cohort study used a prospectively maintained institutional database from a single Japanese institution. Consecutive patients who underwent primary THA between January 2021 and December 2023 were included. FJS-12 was assessed at 3 and 12 months postoperatively, and falls occurring between 3 and 12 months postoperatively were identified at the 12-month visit based on patients' self-report over this 9-month interval. Modified Poisson regression was used to examine the association between FJS at 3 months and subsequent falls. Multiple linear regression was used to examine the association between fall occurrence and FJS at 12 months, adjusting for FJS at 3 months. Results Overall, 623 patients were analyzed (mean age 70.8 years; 85.2% female). Ninety-nine patients (15.9%) experienced at least 1 fall between 3 and 12 months postoperatively. Lower FJS at 3 months was associated with a higher risk of subsequent falls. Fall occurrence was associated with lower FJS at 12 months, independent of FJS at 3 months and other covariates. Conclusions Early postoperative joint awareness was associated with subsequent falls after THA, and falls were associated with lower FJS at 12 months. The FJS-12 may provide additional patient-reported information when assessing postoperative fall risk.