Pre-operative predictors of post-operative falls in people undergoing total hip and knee replacement surgery: a prospective study

Pazit Levinger, Elin Wee, Soula Margelis, Hylton B. Menz, John R. Bartlett, Neil R. Bergman, Stephen McMahon, Keith D. Hill

Pain and disability often persist following hip (THR) and knee replacement (TKR) surgery predisposing patients to increased risk of falling. This study identified pre-operative predictors for post-operative falls in TKR and THR patients, and the incidence and circumstances of falls in the 12 months post-surgery. A survey was undertaken of patients before THR and TKR, and was repeated 12 months post-operation. The survey included (1) medical history and medications usage, (2) pain and function, (3) health-related and physical activity and (4) fear of falls and history of falls questionnaires. Patients were classified as 'fallers' (≥1 fall) or 'non-fallers' based on prospectively documented falls in the 12 months post-surgery. Binary logistic regression was conducted to identify independent pre-operative predictors of incident falls status. Eighty-two of the 243 participants (33.7%) reported ≥1 fall in the 12 months post-operatively [60 (34.1%) patients following TKR and 22 (32.8%) following THR]. The logistic regression model was statistically significant, χ (2) = 24.731, p < 0.001, the model explaining 22% of the variance in falls, and correctly classifying 73.7% of cases as fallers or non-fallers. Reduced SF-36v2 general health sub-scale, increased planned physical activity and previous falls in the preceding year were predictors of falls. Those reporting ≥1 fall pre-operatively were three times more likely to fall post-operatively. People awaiting hip or knee joint replacement surgery might present with complex conditions that predispose them to greater risk of falling post-operation. Review of general health and history of falling is recommended pre-operatively to identify patients at risk.