J Man Med 1989; 4 (3): 96
(Abstracts of the 9th International Congress of the Federation Internationale de Medecine Manuelle, London, 18-22 September 1989)
It has been generally accepted that the presence of increased muscle tone is necessary to perceive a joint dysfunction as a painful condition. Therefore, special attention should be paid to its exact evaluation. However, the increased muscle tone due to impaired function has been widely ignored. This may be the reason why almost exclusively only one term (spasm) is used to describe increased muscle tone of evidently different pathogenesis. At least five types of "muscle spasm" should be differentiated. They occur due to dysfunction:
(1) of the limbic system,
(2) at the segmental level (interneurons?),
(3) due to incoordinated muscle contraction (trigger points?),
(4) to direct pain irritation, and
(5) to overuse (tightness).