The biceps are two muscles in the upper arm that originate separately at the top of the shoulder and attach at the elbow. Tendons attach these muscles to the bone, and one part of the muscle passes inside the shoulder joint and attaches directly to the shoulder. The biceps muscle includes two tendons that are attached to the shoulder and travel the length of the upper arm and insert below the elbow.
The biceps muscle is responsible for bending (or flexing) the elbow and rotating the forearm. One of the tendons is called the long head of the biceps muscle, while the second tendon is called the short head. The long head tendon is attached to the upper arm bone, while the short head attaches the muscle to a bony bump on the shoulder blade called the coracoid process.
A biceps tendon rupture occurs when the biceps muscle is torn from the bone at the point of attachment to the shoulder or elbow. Most commonly, the biceps tendon will tear at the long head of the biceps at the upper arm bone, leaving the other attachment of the shoulder intact. The arm can still be used after this type of occurrence, although, the individual will feel weakness in his / her shoulder and upper arm.
A tear can either be partial when a part of the tendon remains intact and only a small portion is torn away from the bone, or it can tear completely, where the entire tendon is torn away from the bone. Usually, the biceps tendon is torn at the shoulder of an individual. Biceps tendon ruptures may also occur in any patient who performs repetitive overhead lifting or work in occupations that requires lifting heavy objects, and in athletes who lift weights or participate in any aggressive sports.
The biceps are used countless times a day for strength and rotation of the arm – because of the frequent use and the demand of these muscles, biceps tendon injuries are common and may cause sudden and severe shoulder or elbow pain.