Sensing of Leg Position and Movement

This study will collect information on how people sense leg position and movement. The findings may help scientists develop better ways to evaluate and treat joint problems. Healthy adult volunteers between 21 and 40 years of age may be eligible for the study. Candidates are screened with a brief questionnaire and examination to determine their strength, flexibility, and sensation. Participants sit on a specially designed chair, with their foot and leg placed in a custom-made apparatus that controls knee and ankle movements. The skin is marked to indicate the area of interest for ultrasound assessment of muscle. Subjects respond to joint position changes for several trials. The procedure takes a maximum of 2.5 hours to complete. ...