Quantifying Physical Resilience after Knee or Hip Surgery in Older Australian Women Based on Long-Term Physical Functioning Trajectories.

Abstract

To improve outcomes after knee or hip surgery, better insight is needed in long-term recovery patterns in the context of ageing-related decline. We examined long-term trajectories of physical functioning (PF) in older women with and without hip and knee surgery and described profiles of cases with higher and lower resilience after surgery. This observational study used data from 10,434 women (73-79 years) who completed survey 2 of the Australian Longitudinal Study on Women's Health. Data were used from surveys 2 (1999) to 6 (2011). Covariable-adjusted linear mixed models were run to examine the surgery-by-time (-12 to +12 years) interaction in association with PF (SF-36 subscale). The differences between observed and expected PF were calculated, with positive/negative values reflecting higher/lower resilience, respectively. Women with hip surgery (n = 982) had lower PF than those without surgery (n = 8,117) (p < 0.001). Among hip surgery patients, the decline was more rapid pre-surgery than post-surgery (Δslope = -0.7, p < 0.001). Women with knee surgery (n = 1,144) had lower PF than those without surgery (n = 7,971), but with a slower rate of decline (p = 0.01). Among knee surgery patients, the rate of decline was similar pre- and post-surgery (Δslope = -0.3, p = 0.25). Both in hip and knee patients, women with higher resilience had fewer comorbidities and symptoms and were more often physically active and independent in daily activities than those with lower resilience (all p < 0.05). Compared with women without surgery, PF was lower and declined more rapidly around the time of hip surgery, but not for knee surgery. Women with better long-term recovery after surgery had fewer health problems and were more independent around the time of surgery.