The biceps is one of the large muscles on the front of the arm starting up at the shoulder and extending across the elbow to attach to the upper end of the forearm (on the radial tuberosity). Its main actions are to flex (bend) the elbow as well as to supinate the forearm (rotate your forearm so that the palm of your hand is facing the ceiling).
The distal biceps tendon is one of the larger tendons in the body, capable of transmitting significant force. Distal biceps tendon ruptures most commonly occur when a patient is trying to lift a very heavy weight – as the biceps is overpowered, the elbow is violently extended and the tendon is pulled away from its insertion on the bone.
This injury tends to occur in individuals who already have a degree of wear and tear within the tendon – tendinosis. Tendinosis usually occurs as a result of overuse but only seems to occur in susceptible individuals. Distal biceps tendon ruptures most commonly occur in males aged 35-55, a patient demographic that seems to be particularly susceptible to both tendinosis and the tendency to try to lift things heavier than one can!!!
Distal biceps tendon ruptures are often quite dramatic when they occur. Many patients report an audible pop with associated anterior elbow pain. As the muscle retracts, the contour of the biceps changes the appearance of the arm creating what is known as a “popeye sign”. Over the following few days, characteristic bruising will appear anteriorly over the elbow and down the inside of the forearm.
The diagnosis of this injury is usually quite apparent from history and clinical examination alone, although sometimes and ultrasound or MRI can be used to conform a diagnosis if there is any doubt, particularly in the setting of partial ruptures.
Surgery for Distal Biceps Injuries
Left untreated, this injury results in weakness of forearm supination (40-50%) and elbow flexion (approximately 30%). In certain patients, this may be an acceptable outcome, however in most active individuals, surgical repair can reliably restore the normal contour, movement and power of the elbow.
Surgery involves retrieving the ruptured and retracted tendon and reattaching it to the bone at the upper end of the forearm. This can be done in a number of different ways but Dr Alexander’s preferred technique is to use a volar approach and deploy a metallic button to secure the tendon. Sometimes this can be done via a single surgical incision but often a small accessory incision is made further up the arm if the tendon has retracted significantly.
Following surgery your arm will be placed into a sling. You will be given detailed rehabilitation instructions and one of our physiotherapists will be able to guide you through this process. In the early stages, rehab is a careful balance between protecting the surgical repair and getting the elbow and forearm moving again to prevent stiffness. Dr Alexander will take time to assess your individual circumstances and discuss the implications of this injury on return to various activities including driving and work.