MR imaging of muscle injury of lower limb in professional athletes

Muscular injuries are a leading cause of time loss in elite sport, and radiology plays a crucial role in diagnosis, prognosis, and return-to-play strategy. Indirect failure at the myotendinous or myo‑aponeurotic junction is the predominant site of injury, particularly in high‑power bi‑articular muscles (biceps femoris, rectus femoris, medial gastrocnemius, and adductor longus); direct contusions, avulsions, and penetrating trauma are less common but clinically consequential. Recognition of connective‑tissue scaffolds (the biceps femoris distal “zipper,” rectus femoris central septum, soleus central tendon) is critical because disruption of thick tendinous elements prolongs recovery and raises reinjury risk. This review integrates current knowledge on injury biomechanics, muscle-specific architectural vulnerability, optimal magnetic resonance imaging (MRI) techniques, imaging appearances across the tear spectrum, and the performance of prevailing classification systems.