| Discussion: |
Muscle strains commonly present acutely after a discrete traumatic episode. However, one exception is the rectus femoris tear, which may present as a minimally tender palpable mass that mimics a soft tissue tumor. The injury may occur acutely and/or represent sequelae of chronic microtrauma.
The rectus femoris muscle is the most commonly injured component of the quadriceps muscle, due to its superficial position, as well as the fact that it traverses both the hip and the knee joints. The typical location for rectus femoris injury involves the distal interface with the quadriceps tendon. However, there is also a more proximal site of injury (seen in this case), located at the myotendinous junction of the deep tendon of the indirect head. The proximal tendon of the rectus femoris is composed of 2 parts: a superficial component arising from the direct head, as well as the aforementioned component arising from the indirect head.