Thigh muscle-tendon injuries are common among athletes. These injuries can be severe and require long rehabilitation or even surgical treatment. They also tend to recur quite often, causing prolonged time off from sports. More research on the etiology, diagnostics, and treatment of these injuries is needed to develop better prevention and management. This study was performed to investigate the mechanisms of thigh muscle-tendon injuries, a novel scanning position for diagnosing proximal hamstring tendinopathy, and patient outcomes after surgical treatment of hamstring injuries.

In the study of mechanisms of high-grade hamstring injuries in professional football (soccer in this thesis), we found injuries occurring during high-speed movements, typically involving hip flexion, knee extension, and trunk flexion, and most commonly affecting the biceps femoris. In addition to sprinting and stretching, also mixed-type injuries occurred.

Most (80%) of the rectus femoris injuries among male professional soccer players occurred during kicking, often causing total rupture of at least one tendon. Sprinting injuries also led to total ruptures, whereas change of direction only caused partial tears.

In the study of severe adductor longus injuries in professional soccer players, we found closed kinetic chain actions, such as reaching for the ball, being most frequently present at the time of injury. Hip extension, abduction, and external rotation were typically seen.

In proximal hamstring tendinopathy, diagnostics can be very challenging, and the condition may be difficult to treat. In this study, we presented the novel hip flexion scanning position and proved its additional value in magnetic resonance imaging diagnostics of proximal hamstring tendinopathy.
In a systematic review, we found that surgical treatment of hamstring tendon ruptures leads to successful outcomes, especially when surgery is performed early.