Temporal and Kinetic Characteristics of Different Sit-to-Stand Movement Strategies in Females with Osteoporotic Vertebral Compression Fractures

Abstract

The purpose of this investigation was to objectively identify the temporal and kinetic features of the three different sit-to-stand (STS) strategies in patients with osteoporotic vertebral compression fractures for possible future reference. Fourteen female patients, aged 68.2±7.8 years, with osteoporotic vertebral compression fractures were included. Subjects sat on a height adjustable, armless, backless chair with their feet on force plates to perform STS using simple, flexion, and extension strategies. Temporal and kinetic features, including STS duration, horizontal and vertical momentums, and maximal left–right ver-tical force differences (Max-LR-VF-Diff) were measured. The flexion strategy allowed for the longest overall STS duration. The flexion strategy's peak horizontal and vertical momentums during STS were 44% and 24% smaller in magnitude, respectively, than in the simple strategy. The extension strategy had a smaller Max-LR-VF-Diff between both feet than the simple strategy. We found that the flexion strategy gave a slower STS movement, which may have a role in simplifying the neuromuscular demand for motor control and trunk stability. The extension strategy seemed to offer a more symmetric STS pattern by reducing left–right weight distribution difference, and its clinical relevance warranted further investiga-tion. (Tw J Phys Med Rehabil 2006; 34(3): 129 -139)