Abstract
The objectives of this study were to evaluate the effect of exercise on knee joint laxity. If exercise induced laxity is physiological, incorporation of this quality into a ligament replacement material would be indicated. Twenty recreational long distance runners average age 41 (range 24 to 50 yr) were tested before and immediately after 30 minutes of running. Using a computerized goniometer type instrument (Acufex KSS), knee flexion, axial tibial rotation and anterior-posterior tibial displacement were simultaneously recorded, while the runners underwent tests of static as well as dynamic knee joint laxity. At 30 degrees of knee flexion, a maximum increase of 16 per cent in mean total anterior-posterior laxity post-exercise was found. At the examination 30 minutes post-exercise, laxity at 30 degrees of knee flexion was still increased. However, laxity at 90 degrees of knee flexion had decreased to pre-exercise levels or below. Anterior tibial displacement, recorded during eccentric quadriceps activity (0 to 90 degrees of knee flexion) with weights attached to the foot, showed a maximum of 18 per cent increase in total anterior-posterior laxity post-exercise. It is suggested that the laxity increase is caused in part by a true ligamentous laxity increase, and in part by a decreased resting tone of the fatigued muscles.
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Selected References
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- Abrahams M. Mechanical behaviour of tendon in vitro. A preliminary report. Med Biol Eng. 1967 Sep;5(5):433–443. doi: 10.1007/BF02479137. [DOI] [PubMed] [Google Scholar]
- Henning C. E., Lynch M. A., Glick K. R., Jr An in vivo strain gage study of elongation of the anterior cruciate ligament. Am J Sports Med. 1985 Jan-Feb;13(1):22–26. doi: 10.1177/036354658501300104. [DOI] [PubMed] [Google Scholar]
- Hooley C. J., McCrum N. G., Cohen R. E. The viscoelastic deformation of tendon. J Biomech. 1980;13(6):521–528. doi: 10.1016/0021-9290(80)90345-0. [DOI] [PubMed] [Google Scholar]
- Markolf K. L., Bargar W. L., Shoemaker S. C., Amstutz H. C. The role of joint load in knee stability. J Bone Joint Surg Am. 1981 Apr;63(4):570–585. [PubMed] [Google Scholar]
- Noyes F. R. Functional properties of knee ligaments and alterations induced by immobilization: a correlative biomechanical and histological study in primates. Clin Orthop Relat Res. 1977 Mar-Apr;(123):210–242. [PubMed] [Google Scholar]
- Skinner H. B., Wyatt M. P., Stone M. L., Hodgdon J. A., Barrack R. L. Exercise-related knee joint laxity. Am J Sports Med. 1986 Jan-Feb;14(1):30–34. doi: 10.1177/036354658601400106. [DOI] [PubMed] [Google Scholar]
- Steiner M. E., Grana W. A., Chillag K., Schelberg-Karnes E. The effect of exercise on anterior-posterior knee laxity. Am J Sports Med. 1986 Jan-Feb;14(1):24–29. doi: 10.1177/036354658601400105. [DOI] [PubMed] [Google Scholar]
- Stoller D. W., Markolf K. L., Zager S. A., Shoemaker S. C. The effects of exercise, ice, and ultrasonography on torsional laxity of the knee. Clin Orthop Relat Res. 1983 Apr;(174):172–180. [PubMed] [Google Scholar]
- Tipton C. M., Matthes R. D., Maynard J. A., Carey R. A. The influence of physical activity on ligaments and tendons. Med Sci Sports. 1975 Fall;7(3):165–175. [PubMed] [Google Scholar]
- Viidik A. Elasticity and tensile strength of the anterior cruciate ligament in rabbits as influenced by training. Acta Physiol Scand. 1968 Nov;74(3):372–380. doi: 10.1111/j.1748-1716.1968.tb04245.x. [DOI] [PubMed] [Google Scholar]
- Weisman G., Pope M. H., Johnson R. J. Cyclic loading in knee ligament injuries. Am J Sports Med. 1980 Jan-Feb;8(1):24–30. doi: 10.1177/036354658000800105. [DOI] [PubMed] [Google Scholar]