Bone mineral density, soft tissue body composition, strength, and functioning after hip fracture

Abstract

Background: Although substantial decrements in bone, muscle, and functional ability have been reported to follow the occurrence of hip fracture in elderly women, little is known about the interrelation of these consequences. The authors evaluated the associations among physiologic and functional factors during recovery from hip fracture to determine whether any consistent sequence of events followed and whether markers of functional outcomes could be identified.

Methods: Two hundred five community-dwelling women aged 65 years and older who sustained hip fracture between 1992 and 1995 and were admitted to one of two acute care hospitals in metropolitan Baltimore, Maryland, participated in a 1-year prospective cohort study. Bone mineral density, lean mass, and fat mass were measured by dual-energy X-ray absorptiometry during the hospitalization and 2, 6, and 12 months later. Functional limitations were self-reported and grip strength was measured during interviews at the same time points. Correlation coefficients were calculated for all possible pairs of measures and time points.

Results: Losses of femoral neck bone mineral density and lean body mass and gains in fat mass were observed. Grip strength showed early improvement but declined by 1 year to levels close to those seen during hospitalization. Functional outcomes showed minimal correlation with bone or body composition and only moderate correlation with strength.

Conclusions: Physiologic and functional declines follow hip fracture in elderly women. These are largely independent of one another and suggest that interventions to maximize recovery must simultaneously target multiple areas, including bone, muscle, strength, and function.