Distal Biceps Rupture

Distal biceps ruptures usually occurs after a sudden lift or when the elbow is loaded in an unusual way
- Dr Duckworth

The distal biceps is important for flexing (or bending) your elbow and also for rotating your forearm outwards (supination).

The biceps tendon starts in the shoulder and attaches down around the elbow joint. In the shoulder it has 2 different origins, one from inside the shoulder joint and the other from a bone outside the joint. These 2 tendons then join and form the main muscle mass in the front of your arm which you can easily palpate. This muscle mass then becomes one single thick tendon (the distal biceps tendon) and attaches to the radial tuberosity which is a bone found around your elbow joint.

When you contract or flex your elbow you can easily palpate this tendon. The distal biceps is important for flexing (or bending) your elbow and also for rotating your forearm outwards (supination). Therefore when this tendon ruptures you lose strength of flexion and supination.

For the majority of patients a distal biceps rupture causes significant weakness around their elbow. For these reasons surgery is generally recommended so as to restore function around the elbow. Conservative or non operative treatment is generally recommended for those that have very low demands on their elbow with the understanding that there will always be an element of weakness.

Learn more about biceps rupture repair surgery

How do patients present?

The overwhelming majority of patients that rupture their biceps tendons are male. The injury usually occurs after a sudden lift or when your elbow is loaded in an unusual way (can be forced into extension). The patients are generally aged between 25 and 65 years of age and often the dominant arm is affected. When the tear occurs you often hear or feel a snap and a tearing sensation.

A lump can often be palpated in the lower arm as the tendon retracts around your elbow.

Tenderness is then felt in your elbow crease and bruising can occur within 24 hours. The pain slowly settles but you are generally left with weakness of elbow flexion and weakness of rotating your forearm outwards (the motion used for a screwdriver). When the tendon remains ruptured these actions remain permanently weak.

How is the diagnosis made for distal biceps ruptures?

The diagnosis can generally be made from the patient’s history and physical examination. As mentioned above, bruising is characteristic around the elbow joint, one also finds patients have tenderness around the normal course of the biceps tendon. The biceps tendon when completely ruptured is also very difficult to palpate or feel along its normal course as it often retracts up the arm. If one is unsure of the clinical diagnosis then a more definitive diagnosis can be made with imaging such as an ultrasound or the gold standard test of a MRI scan. Once the diagnosis is confirmed then treatment options can be considered.

How long after I rupture my tendon have I got to have it repaired?

The sooner you are seen after you rupture your tendon the easier it is to repair. Beyond 4 weeks after the injury it is very difficult to repair and the results are not as rewarding. The tendon after the rupture starts to retract up the arm and gets to a stage after 4 to 6 weeks where it can not be brought down to its anatomical position of attachment.