Mobility after proximal femoral fracture: the relevance of leg extensor power, postural sway and other factors.

We studied 40 previously healthy women (median age 83 years 90% central range 77-90) 1 week after surgical fixation of their proximal femoral fracture to establish the significance of leg extensor power, postural sway, age, pre-injury mobility and fracture type in recovery of walking and stair-climbing ability. Subjects demonstrated a range of walking and stair-climbing abilities. Those not mobile all had sway greater than 40.9 cm/1 min and were more likely to have suffered a trochanteric fracture (p < 0.05). These subjects were not the oldest or those with the worst pre-injury mobility, but did report much greater pain (p < 0.05). Multiple linear regression revealed leg extensor power in the fractured leg (LEPf) to be the most important determinant of walking speed (R2 0.40, p < 0.001) and stair climbing time (R2 0.33, p < 0.002). LEPf was less than in the uninjured leg (p < 0.001), and accounted for only 30% of the total power output. LEPf was determined by pain, and not pre-injury mobility or fracture pattern. These findings have implications for the development of rehabilitation programmes.