Isokinetic Muscle Testing: Is It Clinically Useful?

The use of computer-driven muscle-testing devices has become increasingly popular during the past two decades. This expensive equipment allows evaluation of muscles and muscle groups in an isokinetic manner. Isokinetic muscle testing is performed with a constant speed of angular motion but variable resistance. Isokinetic dynamometers have been shown to produce relatively reliable data when testing simple, uniaxial joints, such as the knee, as well as when testing the spine in flexion and extension. Isokinetic strength data are generally not helpful in the diagnosis of orthopaedic abnormalities. Isokinetic testing can be helpful during the rehabilitation of orthopaedic patients, since it allows easy monitoring of progress. It also enables the patient to work on muscle rehabilitation in a controlled manner at higher speeds than are possible with more conventional exercise equipment. An isokinetic rehabilitation program can be easily tailored with concentric and eccentric components that closely resemble muscle actions during occupational and sports activities.