Anatomy and Function of the Distal Biceps
The biceps muscle, one of the muscles in the front of the upper arm (or humerus), has two muscle bellies, or heads, that have distinct attachments at the shoulder. At the other end of the muscle, near the elbow, the two heads of the biceps join together to form a single distal biceps tendon.
This tendon inserts into the radius bone, one of the two bones in the forearm. Through this distal attachment on the radius, the biceps participates in both elbow flexion and supination. Supination is the act of turning the forearm from a palm-down position to a palm-up position, such as when tightening a screw with a screwdriver.
Distal Biceps Injury and Symptoms
Injuries to the distal biceps tendon can be partial or complete ruptures. They commonly occur in the dominant arm of middle-aged adults. Unanticipated loading of the tendon is a common mechanism of injury, for example when a heavy object unexpectedly falls and the biceps contracts to catch it while the elbow is rapidly straightened.
Typically, the injured tendon has some pre-existing degeneration (tendinosis) that makes it vulnerable to injury. People who smoke and those who are physically inactive are more likely to rupture their biceps tendon when it is subjected to heavy loads.
- Pain at the front of the elbow, sometimes with an audible pop at the time of injury
- Bruising around the elbow
- A visible or palpable gap at the elbow where the tendon previously attached
- A rounded mass in the lower biceps muscle if the tendon retracts toward the shoulder
- Weakness in elbow flexion and forearm supination (supination is typically more affected)
How are Distal Biceps Ruptures Treated?
There are several options available for the treatment of a torn distal biceps tendon, ranging from conservative treatment to surgical intervention. Most patients will have surgery, but there is a role for non-operative treatment in lower-demand individuals or those who are poor surgical candidates.
Non-Operative Treatment
A non-operative, physiotherapy-led programme will focus first on reducing pain and maintaining full elbow movement. Anti-inflammatory medications may also be prescribed. Once pain has decreased and motion is good, treatment progresses to strengthening the muscles around the elbow. Painless function with some residual weakness and early fatigue of supination can be achieved through conservative management.
Surgical Treatment
Surgical management aims to restore the distal biceps tendon anatomy by repairing the tendon at its insertion site on the radius. Surgery is typically performed through an open incision at the front of the elbow, or through a two-incision approach. Fixation techniques include sutures, surgical buttons, anchoring devices, and surgical screws.
Rehabilitation
After surgery, the elbow is typically immobilised for a few weeks before gentle range-of-motion exercises are introduced. The majority of tendon healing is usually complete after two months, at which point light strengthening exercises can begin. Return to full activity is variable, but most patients can expect to be back to their pre-operative activities within 4 to 5 months.
If you have sustained an elbow injury or suspect a biceps tendon problem, early assessment is important. Please contact us to arrange an appointment.