Biomechanical and histological evaluation of muscle after controlled strain injury.


Journal Article

This study correlates force generation and healing in muscle after controlled strain injury. Right tibialis anterior (TA) muscles from 30 rabbits were strained to approximately 80% of failure while the left TA muscles served as control. Both injured and control muscles were then tested for ability to generate force. Seven animals were sacrificed immediately after testing and the muscles were examined grossly and histologically. Remaining animals were retested at 24 hours (N = 7), 48 hours (N = 8), and 7 days (N = 8). Contractile ability following injury was 70.5% of control immediately, 51.1% at 24 hours, 74.5% at 48 hours, and 92.5% at 7 days. Immediate histology showed limited distal fiber rupture and hemorrhage. By 24 hours, histology showed fiber necrosis, infiltration of inflammatory cells, edema, and hemorrhage. At 48 hours there was complete fiber breakdown and intense inflammatory cell proliferation. At 7 days inflammation was reduced and collagen fibrosis more advanced. Our findings demonstrate that injured muscle begins functional recovery by 48 hours despite inflammation and active healing. This suggests that decreasing muscle function seen clinically between 24 and 48 hours following strain injury may result from pain due to inflammation. Scarring and fibrosis seen at 7 days may explain the frequent recurrence of injury to strained muscles.

Full Text

Cited Authors

  • Nikolaou, PK; Macdonald, BL; Glisson, RR; Seaber, AV; Garrett, WE

Published Date

  • January 1987

Published In

Volume / Issue

  • 15 / 1

Start / End Page

  • 9 - 14

PubMed ID

  • 3812867

Pubmed Central ID

  • 3812867

Electronic International Standard Serial Number (EISSN)

  • 1552-3365

International Standard Serial Number (ISSN)

  • 0363-5465

Digital Object Identifier (DOI)

  • 10.1177/036354658701500102


  • eng