Muscle tears as a primary cause of lameness in horses: 14 cases

I cannot say it better than they do: This study indicates that conservative management of muscle tears can result in favorable long-term outcomes. I would add that rehab started early and slowly may be important to prevent the injury from fibrosis resulting in shortening of the muscles reach, see the article associated with this forum for more.
DrO

Can Vet J. 2020 Apr;61(4):389-395.
Muscle tears as a primary cause of lameness in horses: 14 cases (2009-2016).
Cullen TE1, Semevolos SA1, Stieger-Vanegas SM1, Duesterdieck-Zellmer K1.

Author information:
1. Department of Clinical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, Oregon 97331, USA.
Abstract

This study describes clinical and ultrasonographic findings and outcomes of horses with lameness associated with muscle tears. Records of horses diagnosed with muscle tears were retrospectively evaluated. Horses in which one or more muscle tears were confirmed ultrasonographically and lameness was associated with the tear were included in the study (n = 14). Eight horses had tearing of a single muscle, 6 horses had 2 or more muscles involved. Twelve of 14 horses survived to discharge and were alive at follow-up (8 to 90 months). Recovery time ranged from 6 to 52 weeks (mean: 19.8 weeks); 6 to 16 weeks for single muscle injuries and 12 to 52 weeks for multiple muscle injuries. Of the 12 long-term survivors 3 had chronic lameness/stiffness preventing return to their previous activity level and 9 returned to equal or greater level of activity. No statistically significant difference existed between outcomes and location of injury or number of muscles injured. Key clinical message: This study indicates that conservative management of muscle tears can result in favorable long-term outcomes.