Upper extremity joint stresses during walkerassisted ambulation in post-surgical patients.

BACKGROUND A walker is a common device prescribed for ambulatory assistance for individuals with balance difficulties or to reduce lower extremity demands following injury or surgery. The long-term use of a walker imposes significant demands on the patient's upper extremities that may lead to increased risk for development of secondary conditions such as wrist, elbow or shoulder pain. OBJECTIVE To describe the joint kinematics, forces and moments of the wrist, elbow and shoulder in a sample of twenty patients that were using a walker as a result of total joint surgery of the hips and knees. METHODS Three-dimensional upper extremity kinematics were recorded using a motion capture system synchronized with forces and torques transmitted through a walker instrumented with force transducers in the handles. RESULTS Compressive forces were found to be nearly 20% of the body weight at each of the upper extremity joints, both surgical and non-surgical sides, being the greatest force at the wrist and decreasing proximally. Compression forces were greater in the non-surgical side limb at the wrist and at the elbow. CONCLUSION Our findings indicated that loads on upper extremity joints associated with the use of a walker for assisted ambulation are high and further studies are needed to address the cause-effect relationship between the actual joint loading and the development of secondary musculoskeletal upper extremity complaints in more frail patients.