Biceps is a muscle that lies in the upper arms. It lies between the elbows and the shoulder. Biceps are two-headed muscles and contain the long head and the short head. Both of these heads arise from the spatula and join to become a single muscle. The major function of the biceps is to flex and supinate the forearm. Some conditions of the biceps muscle include strain of the biceps, proximal biceps tendinitis, rupture of the tendons, and contracture. Treatment varies depending upon the extent of damage and includes pain medication, physical therapy, and surgery.