Diagnostic Musculoskeletal Ultrasound in the Evaluation of the Lateral Proximal Hamstring (Biceps Femoris).

Hamstring muscle injuries are among the most common lower-extremity injuries in active individuals. Hamstring injuries follow a consistent pattern with a consistent medical history, which includes a sudden, explosive type of movement (sprinting, kicking, jumping, or lunging). The onset of pain is usually acute in the posterior thigh. They may describe a "pop," "snap," or sensation as if someone kicked them in the back of the thigh. An accurate diagnosis of lateral hamstring overuse, partial tears, or ruptures is essential for appropriate treatment planning and optimizing patient outcomes. Diagnostic musculoskeletal ultrasound (MSKUS) offers a portable, real-time, and cost-effective alternative that is gaining traction in rehabilitation and sports medicine settings. MSKUS has emerged as a valuable, non-invasive imaging modality for evaluating hamstring injuries, including tendinopathy, muscle strains (partial tears), and ruptures. MSKUS is excellent at detecting changes in tendon and muscle composition and continuity. This manuscript will review the utility of MSKUS in evaluating lateral hamstring tendon and muscle injuries, including anatomy, common injury mechanisms, sonographic techniques, and clinical implications for those in the rehabilitation profession. By integrating MSKUS into clinical practice, providers can improve diagnostic accuracy, enhance diagnostic confidence, monitor healing progression, and guide rehabilitation strategies to achieve optimal patient outcomes for those with hamstring injuries.