Semitendinosus originates from which structure?

• A. Ischial tuberosity
• B. Proximal, medial shaft of tibia
• C. Greater trochanter
• D. Head of fibula

Answer: (A)

Semitendinosus is a hamstring muscle that starts from the ischial tuberosity, the sit bone of the pelvis. This location provides a strong anchor for a muscle that spans the hip and knee, allowing it to help with hip extension and knee flexion. From there, the tendon travels down the back of the thigh to insert on the proximal medial surface of the tibia (part of the pes anserinus). The other options aren’t correct origins: the proximal medial tibia is where the muscle attaches distally, not where it begins; the greater trochanter is a hub for other hip muscles, not the hamstrings; and the head of the fibula is the insertion point for the long head of the biceps femoris, not the semitendinosus.