Popliteus is a small muscle at the back of the knee joint designed to ‘unlock’ the knee. When the knee is completely straight the popliteus acts to slightly rotate the tibia in order for the knee to then bend. As its action is small, the popliteus muscle is not overly powerful yet rather important for normal function when walking.
Acute injury to the popliteus is uncommon and usually results from either motor vehicle accidents or falls resulting in hyperextension of the knee. An injury to the popliteus can cause difficulty straightening the knee as well as pain and weakness when forcefully bending the knee. Popliteal injuries also result in pain at the back of the knee which is often tender to touch.
In the early stages, treatment generally involves rest, ice and taping to avoid stretching the injured tissue. After the acute phase physiotherapists play a large role in restoring the range of movement to the knee joint and prescription of strengthening exercises to ensure appropriate healing and function is restored to the muscle.