Experimental muscle strain injury. Early functional and structural deficits and the increased risk for reinjury.

Published

Journal Article

The structural and functional strength of a muscle immediately after an experimentally created strain injury was examined to provide clinically relevant information for the early treatment of muscle strain injuries. The extensor digitorum longus muscles of 12 adult male rabbits were studied. Contractile force and shortening, and peak load were determined for control muscles. A nondisruptive strain injury was created by stretching the experimental muscles just short of complete rupture. Contractile force generation and shortening, and peak load were determined after the experimental strain injury. Peak load was 63% and elongation to rupture was 79% for the experimental muscles relative to the controls. Statistically significant lower values for contractile force generation and shortening were also seen in the experimental muscles. Histologic and gross examinations revealed that incomplete disruptions occurred near the distal muscle-tendon junction. These experimental data suggest clinical implications, such as 1) a muscle-tendon unit is significantly more susceptible to injury following a strain injury than normal muscle, 2) early return to the uncontrolled environment of athletic competition may place the injured muscle at risk for further injury, and 3) therapeutic regimens designed to achieve an early return to competition may further increase the risk for additional injury by eliminating protective pain mechanisms. Although the decrements in peak load and elongation to failure are less than normal muscle, the values seem high enough to allow mobilization of the injured extremity and functional rehabilitation.

Full Text

Duke Authors

Cited Authors

  • Taylor, DC; Dalton, JD; Seaber, AV; Garrett, WE

Published Date

  • March 1, 1993

Published In

Volume / Issue

  • 21 / 2

Start / End Page

  • 190 - 194

PubMed ID

  • 8465911

Pubmed Central ID

  • 8465911

International Standard Serial Number (ISSN)

  • 0363-5465

Digital Object Identifier (DOI)

  • 10.1177/036354659302100205

Language

  • eng

Conference Location

  • United States