This document describes the posteromedial and posterolateral approaches to the knee. The posterolateral approach, also called the Henderson approach, involves an incision along the lateral side of the knee to access the posterolateral compartment. The direct posterolateral approach uses the interval between the popliteus and soleus muscles to expose the upper lateral tibia. The posteromedial approach, also a Henderson approach, involves an incision along the medial side through the semimembranosus and semitendinosus muscles to access the posteromedial compartment. A direct posteromedial approach uses the interval between the semimembranosus complex and medial head of gastrocnemius muscle. Both approaches aim to provide