Proximal Hamstring Injuries

Hamstring injuries exist on a spectrum of severity. A hamstring strain is the most common type, involving overstretching of the muscle fibers or tendon without a true tear. A partial tear occurs when a portion of the muscle or tendon fibers ruptures, while a complete tear means the full thickness of the muscle or tendon has given way. The most severe injury is a hamstring avulsion, in which the tendon fully separates from its attachment at the ischial tuberosity (the sit bone of the pelvis). On rare occasions, the tendon pulls a fragment of bone away with it — known as a bony avulsion — which is commonly seen in high-energy sports such as sprinting, skiing, and weightlifting.

Hamstring injuries typically result from sudden, explosive movements such as sprinting, jumping, or rapid changes in direction. Several factors can increase your risk, including a significant strength imbalance between the quadriceps and hamstrings, an inadequate warm-up prior to activity, poor running mechanics, reduced hamstring flexibility, and muscle fatigue from overtraining. Prior hamstring injuries that were not fully rehabilitated are also a leading risk factor for re-injury. Age-related changes in muscle elasticity and training on uneven or unpredictable surfaces can further contribute to injury.

The hallmark symptom of a hamstring injury is sudden, sharp pain in the back of the thigh or near the buttock. Depending on the severity, patients may also experience swelling, bruising, muscle weakness, spasms, and difficulty fully straightening the leg. In more serious injuries, an audible pop or snap may occur at the moment of injury, and walking or bearing weight on the affected leg may become difficult.

A thorough evaluation begins with a detailed history of your symptoms, activity level, and any prior injuries. During the physical examination, Dr. Mark Cinque assesses for tenderness, swelling, bruising, and weakness. In cases of complete avulsion, the retracted muscle belly may be visible or palpable as a bunched-up mass at the back of the thigh. X-rays can identify bony avulsion fragments, while an MRI remains the gold standard for characterizing the exact location, extent, and degree of tendon retraction — information that is essential for guiding treatment decisions.