Muscle injury

Muscle injuries is a broad term encompassing many pathologies and these are common injuries in both elite and amateur athletes as well as in the general population. 

Clinical presentation

Typically, muscle injuries present with pain and loss of function. Clinically, they can be graded as ¹:

• grade 1: no appreciable muscle tearing, <5% loss of function/strength
• grade 2: damage to the musculotendinous junction (MTJ); reduced strength; some residual function
• grade 3: complete tear of the MTJ; loss function +/- a palpable gap

Pathology

Muscle injuries can consist of ^1-3:

• direct trauma
  • muscle contusion
    • acute
    • subacute
    • chronic (myositis ossificans)
  • penetrating trauma with laceration (rare)
• indirect trauma
  • delayed onset muscle soreness (DOMS)
  • muscle tear/strain
    • proximal or distal MTJ
    • myofascial
  • acute avulsion injury

Classification

• British Athletics muscle injury classification