I have to assume that you mean the biceps tendon in your upper extremity. There is a hamstring tendon in the thigh called the biceps femoris, which can tear at the origin in the pelvis or at its attachment on the fibula at the knee. In the upper extremity, the biceps muscle has two tendons that are attached in the shoulder, thus, why it is called “bi”ceps. The muscle has one tendon attachment at the elbow. The biceps muscle helps to bend or flex your elbow, but it also is an important muscle for supinating the forearm ( turning your forearm with the palm of your hand pointing towards the ceiling ). Tearing of the biceps at the elbow is most often treated with surgery to repair the tendon back to the attachment site. Most patients regain full motion and function after surgery and the rehabilitation, and strength restoration is around 90-95%. For those that chose to not have surgery, they can expect approximately 30% loss of elbow flexion strength and 40% loss of forearm supination strength. In the shoulder, tears of one of the two tendons are common but often only results in a cosmetic difference to the contour of the arm ( Popeye deformity ). Strength loss is minimal, with supination strength usually being diminished by 10-15%. For some patients, especially those that require good forearm supination strength and endurance, a reattachment of the biceps in the shoulder can also be performed.