Picture of the biceps
The biceps is the large muscle at the front of the upper arm, located between the elbow and shoulder.
Its primary function is to flex the forearm. These are the muscles that are often a key focus of muscle building programmes. Weight lifters often seek to build these muscles as a sign of strength. As the name suggests, the biceps has two muscle heads that work as a single muscle. They are the short head and long head.
The biceps is attached to the bones of the arm by tough, rubbery tendon cords. The proximal biceps tendons connect the bicep to the shoulder joint. The distal biceps tendons connect the bicep muscle to the bones of the forearm - the radius and the ulna. When the biceps contracts, it levers up and flexes the arm.
Biceps tendonitis: This describes an inflamed and painful biceps tendon. It can be caused by an injury that happens during sport, or by overuse of the biceps that triggers repetitive strain injury (RSI).
Biceps strain: This can be caused by stretching the biceps too much and causing tears in the muscle fibres or tendons. It can happen during sport or training and symptoms include tenderness, pain and swelling. Poor conditioning technique, fatigue or inadequate warm-up can increase the chance of a strain.
Proximal biceps tendon rupture: This involves a complete tear of one of the two tendons attaching the biceps to the shoulder. They are the most common biceps ruptures and often happen in middle age as a result of wear and tear. A torn biceps in younger people can happen during weightlifting, or from a hard fall with the arm stretched out. Patients often report a snapping sensation with sudden, sharp pain in the upper arm as far as the elbow. Bruising may develop and the muscle may appear to bulge.
Distal biceps tendon rupture: This involves a tear of the biceps tendon in the forearm. It is relatively unusual but can be a result of a single traumatic event such as weight lifting or work related heavy lifting or forearm twisting. A sudden, sharp pain is usually felt in the front of the elbow. Acute pain may subside after several hours and be replaced by a dull ache and weakness in the forearm.
Proximal biceps tendonitis: This can be caused by repetitive flexing of the biceps that irritates the proximal biceps tendon. The main symptom is pain in the shoulder and biceps.
Biceps contracture: This is when the biceps permanently contracts, often after a stroke. As a result the elbow is bent.
Diagnosing biceps conditions
Your GP may diagnose biceps tendonitis based on:
- The severity of pain
- Medical history (if you have recently injured yourself at work or exercising)
- Manipulating the biceps to assess range of motion