Distal Biceps Ruptures, by James Davidson, MD
The biceps muscle is a key player in the function of the upper and lower arm, therefore, when it has an injury, it can make a significant impact on a person’s function. A distal biceps rupture is the tearing of the biceps brachii tendon from its attachment site. The biceps brachii or “biceps” muscle is located on the front of the humerus (upper arm). It functions to help the shoulder lift the arm forward (flexion), bend the elbow bringing the hand towards the face (flexion), and twist the forearm so the palm is towards the sky (supination). These actions are important for activities such as lifting objects, shutting doors and twisting objects back and forth (doorknobs and screw drivers).
The biceps brachii muscle splits and originates from two origins: short head attaches to the coracoid process (bony projection off of the front of the shoulder blade) and the long head attaches to the top of the glenoid labrum (cartilage ring around the socket). The distal insertion or attachment is to the tuberosity of the radius bone. The radius is one of two bones of the forearm and it is the one on the thumb side, or lateral side (outside). The tuberosity of the radius is a thicker part of the bone close to the elbow. A rupture can cause pain and physical limitations. For this article, the focus will be on distal biceps ruptures or detachments from the radial tuberosity.
The patient is often lifting something too heavy starting with their elbow in extension going into flexion (straight to bent), possibly awkwardly and/or too rapidly. They could also be catching or resisting a falling heavy object causing a distracting injury to the biceps. Patients hear or feel a “pop” which is the tendon detaching from the bone either partially or fully. This is then followed by soreness and weakness. The person will also notice tenderness, swelling and bruising over the biceps muscle. A telltale sign of a biceps rupture is the “Popeye deformity.” When the biceps tendon ruptures, it immediately starts to retract or shrink away from its attachment site causing a bulge or enlargement of the muscle belly and a divot where the tendon used to be. This mimics the look of the classic cartoon character Popeye’s exaggerated biceps muscles.
The best early first aid treatment is ice, sling and getting into your orthopedic provider as quickly as possible for confirmation of diagnosis. Confirmation of strain, partial rupture or full rupture and length of retraction is typically done with physical exam and magnetic resonance imaging (MRI). The longer the delay in diagnosis and treatment, the poorer the outcome. The treatment of choice for a larger partial or full biceps rupture in an active individual is surgical repair, IF it can be done less than five weeks from injury. An ideal timeframe would be two weeks from injury. As stated before, when the tendon ruptures, it retracts and the longer an individual waits, the less likely it can be repaired.
Aside from avoidance, the best thing for a patient is early detection and referral. Surgical repair is reattachment of the distal end of the bicep’s tendon to the radial tuberosity with suture anchor and washer. More delayed presentations to the surgeon can sometimes be repaired with sterile cadaver graft tendons, but that is not the first treatment of choice. The recovery is typically 12 weeks for heavy duty laborers.
There is a nonsurgical treatment alternative for patients with strains, low grade partial tears, chronic tears or patients who cannot tolerate a surgery which is living with the ruptured tendon. The patient will undergo physical therapy to try and regain as much function as possible. To a varying degree, the patient may notice some weakness in shoulder flexion and forearm supination. Several different factors are taken into consideration when choosing the right treatment option for a patient with a distal biceps rupture such as age, activity level, length of time from injury, extent of tear and hand dominance, to name a few.
There are ways to avoid this injury such as keeping the body strong and flexible for the type of physical demands of a person’s job and the lifestyle they lead. Good body mechanics is also key to avoidance. Avoiding rapid awkward lifting of too much weight or trying to catch an object awkwardly can keep a person from overloading their biceps. If a person already has shoulder or elbow pain, they could be more vulnerable to an injury such as a distal biceps rupture. Getting those symptoms addressed earlier could avoid future overuse or repetitive task injuries.