Musculoskeletal ImagingE2659. Hamstrung? MRI Evaluation of the Anatomy and Injuries of the Hamstring Muscle Complex
Gunio D, Jun S, Irish R. Mount Sinai St. Luke's West, New York, NY
Address correspondence to S. Jun (firstname.lastname@example.org)
Background Information: Hamstring injuries are commonly encountered, especially among athletes. Because of the complicated anatomy of the hamstring muscle complex, injuries can occur at multiple levels and may be prone to chronic aggravation. MRI is highly useful in identifying and characterizing the location and severity of these injuries.
Educational Goals/Teaching Points: We Review the basic anatomy of the hamstring muscle complex (semimembranosus, semitendinosus, and biceps femoris) including origins and insertions; and review MRI images of common and uncommon injuries including injuries at the level of hamstring muscle complex origins, mid-substance, and insertions.
Key Anatomic/Physiologic Issues and Imaging Findings/Techniques: The hamstring muscle complex is composed of the semimembranosus, semitendinosus, and the biceps femoris muscles. With the exception of the short head of the biceps femoris, the hamstring muscles span two joints, increasing their susceptibility to injury. Musculotendinous strains and tears of the hamstring muscle complex typically occur during running because eccentric contraction of the hamstrings may be stressed. MRI reliably depicts the location and extent of these hamstring injuries. Fluid sensitive sequences such as proton-density and T2-weighted fat-suppressed sequences or STIR sequences accurately detail tendon tears and avulsions as fluid-signal abnormalities at the site of disruption. Associated hemorrhage and edema are also readily apparent. The multiplanar capabilities of MRI enable a detailed depiction of the muscles and tendons involved.
Conclusion: Hamstring muscle complex injuries are a common sports-related injury. Though the diagnosis of hamstring injury is usually clinically suspected, MRI is a useful adjunct in accurately depicting the location and extent of the injury which may greatly influence treatment and rehabilitation plans for these patients.