Abstract
BACKGROUND: Hip fractures are most likely to occur in older people, and after hip surgery muscle mass and the ability to perform activities of daily living often decline. In this study, we conducted inpatient rehabilitation after surgery for hip fracture and measured changes in muscle mass and physical performance. METHODS: We retrospectively analyzed patients aged 65 years or older who underwent surgery (prosthetic replacement or internal fixation) and inpatient rehabilitation for hip fracture at our hospital between August and December 2020. The training included a joint range of motion exercise, muscle-strengthening exercise, gait training, early mobilization training, and neuromuscular electrical stimulation. We measured the following factors after one and six weeks postoperatively: muscle mass, body weight, fat mass, grip strength, bilateral knee extension strength, ability to walk, and ability to perform activities of daily living. RESULTS: Seventeen patients were included. Median age was 84 years (interquartile range, 72-90). Lower limbs skeletal muscle mass increased (median 4.8 kg to 4.9 kg, p = 0.045), while upper limbs skeletal muscle mass and body weight decreased (median 1.2 kg to 1.1 kg, p = 0.0027), (median 46.8 kg to 45.5 kg, p = 0.0039), respectively. Total skeletal muscle mass and fat mass remained unchanged. Grip strength was maintained, and knee extension muscle strength on the healthy and affected sides increased (healthy side median 10.7 kgf to 13.7 kgf, p = 0.019; affected side median 5.5 kgf to 9.5 kgf, p < 0.001). All patients exhibited improved ability to perform activities of daily living; however, 52.9% of patients regained their pre-injury walking ability. CONCLUSIONS: Our rehabilitation program increased lower limb skeletal muscle mass in patients with hip fractures.