Increased prevalence of fall risk factors in older people following hip fracture

Many people who suffer a hip fracture do not achieve full functional recovery. Simple tests of physical function such as quadriceps strength and postural sway may provide insight into why this population is at increased risk of experiencing further falls and fractures and assist in developing rehabilitation strategies for preventing falls.

To determine whether impairments in a range of physiological measures and specific medical conditions are more prevalent in people who have suffered a fall-related hip fracture than in a matched sample of community-dwelling people without a history of falls.

This case-control study involved 88 older people. The hip fracture group comprised 44 persons aged 64-94 years, assessed on average 7 months following a fall-related hip fracture. An age- and sex-matched control group (older persons who had not fallen in a 12-month period before recruitment) was drawn randomly from community samples.

Compared with the control group, the hip fracture group had markedly reduced quadriceps strength and increased body sway when tested on firm and compliant (foam rubber) surfaces. Patients in the hip fracture group also had higher prevalence rates of poor vision, arthritis and stroke, were taking more medications, were less physically active and perceived themselves to be at greater risk of falling than the control group. No significant differences were apparent for cardiovascular conditions, subjective health status and psychoactive medication use between the groups. Multivariate analyses identified quadriceps strength and body sway on the compliant surface as the most important variables for distinguishing between the hip fracture and no hip fracture groups. These two variables correctly classified 92% of the cases, with equal sensitivity and specificity.

The findings identify an increased prevalence of certain physical fall risk factors among older persons who have suffered a hip fracture. Decreased quadriceps strength and increased postural sway are potentially modifiable. Intervention programs designed to improve performance on these variables among this population require investigation.