Distal Biceps Rupture

What is the distal biceps tendon?

The biceps muscle goes from the shoulder to the elbow on the front of the upper arm. Tendons attach muscles to bone. Two separate tendons connect the upper part of the biceps muscle to the shoulder. One tendon connects the lower end of the biceps to the elbow.

The lower biceps tendon is called the distal biceps tendon. The word distal means that the tendon is further down the arm. The upper two tendons of the biceps are called the proximal biceps tendons because they are closer to the top of the arm. Distal Biceps Tendinopathy

The distal biceps tendon attaches to a small bump on the radius bone of the forearm. This small bony bump is called radial tuberosity. The radius is the smaller bones between the elbow and the wrist that make up the forearm. The radius goes from the outside edge of the elbow to the thumb side of the wrist. It parallels the larger bone of the forearm, the ulna. The ulna goes from the inside edge of the elbow to the wrist.

What is Distal Biceps Tendinopathy?

This degeneration of the tendon attaches the biceps muscle of the upper arm to the radius bone of the forearm. This typically causes pain in the front of the elbow that may be made worse by lifting or twisting motions of the forearm below the elbow.

What happens in distal biceps ruptures?

Tears of the biceps tendon at the elbow are uncommon. They are most often caused by a sudden injury and result in more significant arm weakness than injuries to the biceps tendon at the shoulder.
Once torn, the biceps tendon at the elbow will not grow back to the bone and heal. Other arm muscles make it possible to bend the elbow fairly well without the biceps tendon. However, they cannot fulfil all the functions of the elbow, especially the motion of rotating the forearm from palm down to palm up. This motion is called supination.

Biceps tendon tears can be either partial or complete.

Partial tears. These tears damage the soft tissue but do not completely sever the tendon.

Complete tears. A complete tear will detach the tendon completely from its attachment point at the bone.
In most cases, tears of the distal biceps tendon are complete. This means that the entire muscle is detached from the bone and pulled toward the shoulder.

This strong tendon at the elbow can rupture with a powerful contraction of the biceps muscle. People may feel a pop in the elbow and pain. This usually happens when the tendon is already worn and prone to injury.

The most likely to get a biceps tendon rupture are strength athletes, bodybuilders and heavy manual workers. Generally, males over the age of 35 years. Unlike other tendon ruptures, steroid use is not involved in the rupture of the distal biceps.

What are the risk factors for distal biceps ruptures?

Men, age 30 years or older, are most likely to tear the distal biceps tendon.

Additional risk factors for distal biceps tendon tear include:
– Smoking. Nicotine use can affect tendon strength and quality.
– Corticosteroid medications. Using corticosteroids has been linked to increased muscle and tendon weakness.

How do we diagnose these tears?

After the injury, there is usually localised pain at the front of the elbow, with bruising and swelling. The biceps muscle may retract up the upper arm crating a prominent bump, known as the ‘Popeye’ sign. This is often visibly different to the other biceps when contracting the muscle.

A biceps tendon rupture leads to weakness of the elbow and forearm if not repaired. People have difficulty twisting a screwdriver, turning a key and lifting weights. This is due to a 55% reduction in forearm twisting strength (supination power) and a 36% reduction in elbow bending strength (flexion power).

There is often a “pop” at the elbow when the tendon ruptures. Pain is severe at first, but may subside after a week or two.

Other symptoms include:
⦁ Swelling in the front of the elbow
⦁ Visible bruising in the elbow and forearm
⦁ Weakness in bending of the elbow
⦁ Weakness in twisting the forearm (supination)
⦁ A bulge in the upper part of the arm created by the recoiled, shortened biceps muscle
⦁ A gap in the front of the elbow formed by the absence of the tendon

How do we treat distal biceps ruptures?

Surgery to reattach the tendon to the bone is necessary to regain full arm strength and function.

Nonsurgical treatment may be considered if you are older and less active or if the injury occurred in your non-dominant arm and you can tolerate not having full arm function.

Nonsurgical treatment may also be an option for people who have medical problems that put them at higher risk for complications during surgery.
Nonsurgical Treatment
Nonsurgical treatment options focus on relieving pain and maintaining as much arm function as possible. Treatment recommendations may include:
⦁ Rest. Avoid heavy lifting and overhead activities to relieve pain and limit swelling. Your doctor may recommend using a sling for a brief time.
⦁ Nonsteroidal anti-inflammatory medications. Drugs like ibuprofen and naproxen reduce pain and swelling.
⦁ Physical therapy. After the pain decreases, your doctor may recommend rehabilitation exercises to strengthen surrounding muscles in order to restore as much movement as possible.

Surgical Treatment
Surgery to repair the tendon should be performed during the first 2- 3 weeks after injury. After this time, the tendon and biceps muscle begin to scar and shorten, and restoring arm function with surgery may not be possible. While other options are available for patients requesting late surgical treatment for this injury, they are more complicated and generally less successful.

Procedure. There are several different procedures to reattach the distal biceps tendon to the forearm bone. Some doctors prefer to use one incision at the front of the elbow, while others use small incisions at both the front and back of the elbow.

There are many different techniques for repairing the ruptured biceps tendon. Our prefered method is to use the Endobutton Technique but other methods are equally successful. Please discuss this with Professor Imam.
The biceps tendon ruptures off the forearm bone (radius) and retracts up the upper arm, causing a deformity (known as the ‘Popeye sign’)
A small incision is made over the upper forearm, where the biceps should attach to the radius bone.
The retracted biceps tendon is retrieved through the incision. Sometimes another incision higher up the arm may be required to find the tendon.
The radius is prepared to encourage healing. With the Endobutton technique, the tendon end is actually buried inside the bone to create a strong repair.
Strong sutures are threaded through the tendon in a specific interlocking way to ensure a strong repair of the tendon to the bone. The tendon is then fixed to bone with the Endobutton, suture anchors, an interference fit screw or bone tunnels. In laboratory tests the Endobutton technique has been shown to be the strongest.

Complications. Surgical complications are generally rare and temporary.
⦁ Numbness and/or weakness in the forearm can occur and usually goes away.
⦁ New bone may develop around the site where the tendon is attached to the forearm bone. While this usually causes little limitation of movement, sometimes it can reduce the ability to twist the forearm. This may require additional surgery.
⦁ Although uncommon, the tendon may re-rupture after full healing of the repair.

Rehabilitation. Right after surgery, your arm may be immobilised in a cast or splint.
Prof Imam will soon begin having you move your arm, often with the protection of a brace.
A physiotherapist immediately will see you after the surgery.
Resistance exercises, such as lightly contracting the biceps or using elastic bands, maybe gradually added to your rehabilitation plan.
Since the biceps tendon takes over three months to heal fully, protecting the repair by restricting your activities.
Light work activities can begin soon after surgery, but heavy lifting and vigorous exercise should be avoided for several months.
Although it is a slow process, your commitment to your rehabilitation plan is the most cri
tical factor in returning to all the activities you enjoy.

Surgical Outcome. Almost all patients have a full range of motion and strength at the final follow-up doctor visit. After some time, return to heavy activities and jobs involving manual labour is a reasonable expectation.
After the surgery a sling is applied for comfort. At two weeks the sling is discarded and active movement encouraged. Strengthening is started at around six weeks and by twelve weeks you should be able to return to normal activity including sports.

It can take up to 6-12 months to regain the full strength of your biceps.

What is a Chronic Distal Biceps Tendon Rupture?

The injury typically occurs in men in their fifth decade but may also occur in athletes, especially those involved in contact sports. The cause may be different in these two groups, with evidence of tendon degeneration in the non-athlete group.

The diagnosis of chronic distal biceps tendon rupture is made on clinical grounds by taking a detailed history and physical examination. If there is doubt about the injury, then an ultrasound scan may be helpful; we prefer a magnetic resonance imaging (MRI) scan.

Chronic distal biceps tendon tears can be left untreated if the individual manages daily activities and hobbies without pain or weakness. Some people will notice that the arm feels weaker, especially for activities requiring a strong twisting motion such as a screwdriver.

If the individual has symptoms these can be addressed by bridging the gap between the retracted biceps muscle and the radius bone. This can be done using a tendon tissue graft taken from the patient (autograft) or a tissue donor (allograft). Both techniques have advantages and disadvantages.

SUMMARY

Please see this interview with Professor Imam on the recent updates of management of distal biceps tears from his perspective as a leading surgeon in this procedure.