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1978 Publications

Isokinetic Evaluation Following Leg Injuriesby Gilbert W. Gleim, BA, James A. Nicholas, MD, Joseph N. Webb, RPT - last modified 2013-02-10 00:00
The Physician and Sportsmedicine, Vol. 6, No. 8, August, 1978.


Isokinetic strength testing is relatively new. Consider that the first isometric dynamometer was built in the early 19th century by Reinier in France. By contrast, Thistle published one of the first works on isokinetics in 1967. Perrine discussed the concept of accommodating resistance at a constant angular velocity throughout the range of motion and patented the first isokinetic strength testing device in 1969, and Lumex, Inc. bought the patent and license rights the next year.

Isometric strength testing measures the maximum force exerted at one position. Thus it determines static strength, and one of its major limitations is that it measures the contraction at only one angle. Theoretically, strength output should be the same at any joint angle, but testing throughout the range of motion often shows this to be untrue.

Isotonic testing measures dynamic strength, typically by the one repetition maximum method-the greatest weight that can be moved through a full range of motion one time. The inherent limitation in this method is that strength is measured at the weakest point in the range of motion.

Isokinetic strength testing is a form of isotonic testing with a major difference. By accommodating resistance against a lever moving at a fixed speed, it permits continuous exercise and documents maximum dynamic strength throughout the range of motion.

In this paper we will present data and findings from lower extremity isokinetic testing of subjects with different disorders. We feel this study can help clinicians understand how a localized injury or dysfunction in a given segment of the extremity can cause weakness in the thigh and perhaps even in the spine.