What is Biceps Tendon Rupture?
The biceps muscle in your upper arm has two parts: one begins at the coracoid process, or a small hook-like structure in your shoulder (this is the ‘short head’), and the other starts at a place on your shoulder blade called the supraglenoid tubercle and upper labrum (the ‘long head’). The lower end of the biceps muscle attaches to a small bump on the radius bone in your forearm called the bicipital tuberosity. The biceps muscle helps rotate your forearm and bend your elbow, and the long part of the muscle helps keep your shoulder joint stable. Most biceps muscle tears happen in the long head.
When the long head of the biceps muscle tears, it’s usually treated without surgery. However, if the injury is at the lower attachment point of the muscle, surgery is often necessary. A quick diagnosis and treatment typically leads to a successful recovery.
A tear in the lower biceps muscle can involve a complete or partial pulling away of the muscle from the side of the radial tuberosity. There can also be damage within the muscle substance itself, which can occur in instances like a rope wrapped around the muscle during a tug-of-war game.
What Causes Biceps Tendon Rupture?
A distal biceps rupture occurs when there is too much outward force as the arm moves from a bent to a straight position. This type of injury often happens during activities like weightlifting, wrestling, or physically demanding jobs. On the other hand, a proximal biceps rupture doesn’t usually happen because of a specific kind of injury, but is often connected with a condition where the tissues in the shoulder are damaged, known as rotator cuff disease.
There are several factors that can increase the risk of these types of injuries. These include getting older, smoking, being overweight, use of corticosteroids (a type of medication), and overuse of the muscle. In rare cases, certain conditions or medications can cause these injuries, such as the use of a type of antibiotic called quinolones, diabetes, lupus (a type of autoimmune disease), and chronic kidney disease.
Risk Factors and Frequency for Biceps Tendon Rupture
The rupture of the distal biceps tendon – the tendon located at the elbow – happens about 2.55 times for every 100,000 people each year. Most of these incidents (over 95%) occur in men, particularly those who are middle-aged, between 35 and 54 years old. This type of injury typically affects the arm that is used the most. On the other hand, the rupture of the proximal biceps – the tendon located at the shoulder – usually happens in older patients. While we don’t have exact numbers for how frequently it occurs, we do know it’s more common than the elbow injury in this older age group.
- Rupture of the distal biceps tendon happens about 2.55 times per 100,000 patient-years.
- Over 95% of these cases occur in men.
- The typical age range for this injury is between 35 and 54 years old.
- The injury usually affects the most frequently used arm.
- Proximal biceps rupture, a separate injury that occurs at the shoulder, is more common in older folks.
- The exact frequency of shoulder tendon rupture in older patients isn’t known but it occurs more than the elbow injury in this age group.
Signs and Symptoms of Biceps Tendon Rupture
When the biceps tendon ruptures, patients might experience a sudden, sharp pain in the elbow or shoulder, depending on where the rupture occurred. This is typically associated with a sudden force applied to a flexed elbow. At the time of injury, they might also hear a “pop” in the affected arm. The pain can continue for a few weeks or even months, but may decrease if the tendon is fully torn. Patients often notice a noticeable bulge in the upper arm, known as a “Popeye deformity,” caused by the retraction of the biceps muscle. This may be harder to identify in overweight individuals.
For patients with a distal biceps rupture, they may notice bruising, swelling, and tenderness in the inner elbow area. If the biceps aponeurosis (a fibrous membrane) is involved, the muscle might be retracted to the upper arm, and you could feel a gap where the distal tendon is located. A test can be conducted to identify the absence of the biceps tendon at its distal insertion, known as the ‘hook test’. This test begins with the arm bent at 90 degrees and then turned palm-upwards. The examiner then tries to hook their finger under the tendon, and the healthy tendon should allow this. This test is very specific and sensitive in diagnosing distal biceps tears.
Interestingly, apart from pain, patients with proximal biceps tendon rupture may exhibit very few signs or symptoms. They may have some bruising in the upper arm, sometimes extending up to the elbow. A proximal biceps rupture doesn’t typically lead to any long-term change in elbow or shoulder strength. However, it’s crucial to check for muscle wasting in the shoulder area and shoulder impingement, as proximal biceps tendon disorders often occur alongside rotator cuff problems.
Testing for Biceps Tendon Rupture
If you’ve experienced a sudden, painful pop while performing an action such as lifting weights, this could be a sign of a bicep tendon rupture. Diagnosing this condition typically relies on the patient’s account of the painful incident and the presence of visual signs like a change in the appearance of your biceps muscle (sometimes referred to as a ‘reverse popeye deformity’). You might also find that you’re struggling to bend your elbow or rotate your forearm.
Two tests can potentially confirm the presence of this kind of tendon rupture:
1. Hook Test: During this test, a doctor will try to hook their index finger around the edgy part of your biceps tendon. The test is positive (you have a ruptured tendon) if they can’t hook their finger under the tendon.
2. Ruland Biceps Squeeze Test: In this test, your elbow is bent slightly, and the forearm turned inwards (pronated). The doctor then squeezes the lower part of the biceps muscle. The test is positive (ruptured tendon) if you can’t turn your forearm or wrist outwards (supination).
Sometimes, the rupture can be partial, which could lead to mild symptoms such as pain and weakness without any obvious physical signs. Misdiagnosis can occur in these cases due to their subtle nature.
Imaging tests can further confirm the diagnosis. Ultrasound, a safe and relatively inexpensive technique, can detect the rupture, but the accuracy depends heavily on the skill of the radiography technician. X-ray scans don’t usually provide much help but can sometimes rule out other conditions or reveal injuries related to the rupture.
MRI scans, while rarely necessary for this diagnosis, can help doctors see the difference between a complete and partial tendon tear. They can also detect fractures related to the rupture or if the muscle, not the tendon, is torn.
Treatment Options for Biceps Tendon Rupture
If you experience a biceps rupture, which means that one of the biceps tendons has torn, the initial treatment typically involves using ice, supportive elastic bandages or wraps, anti-inflammatory drugs, and rest. However, the next steps for treatment often depends on where the rupture occurred in the bicep.
Non-surgical treatment like rest and physical therapy is usually enough when the upper-part (proximal) of the biceps tendon has torn. This type of rupture is more common in older individuals. There might be some residual cosmetic changes and occasional muscle cramping in the biceps, but these are often livable conditions. However, younger, more athletic individuals or those who are concerned about the cosmetic appearance of their bicep, might opt for surgery in order to treat the tendon. If there are also issues with the rotator cuff, surgery might be more likely.
For a surgical treatment, a procedure called a biceps tenodesis might be performed, where the tendon is reattached to the bone. Doctors may use various types of implants to secure the tendon in place. This surgery is often effective and can lead to good outcomes for patients.
If the lower part (distal) of the bicep tendon has ruptured, the treatment may be different. Non-surgical treatment methods are often enough for individuals who lead less physically demanding lives or those who have multiple other health conditions. However, these individuals should be aware that there will likely be a loss in strength in the arm, both for turning the forearm and for bending at the elbow.
Surgery is more common for younger, active individuals or those who aren’t willing to experience a loss in arm function. Surgery typically results in less pain in the forearm and elbow and is often pursued in order to regain the maximum strength and functionality of the arm. When the surgery is done is also important. Earlier intervention typically results in a less complicated procedure since waiting might lead to scarring and the need for more extensive surgery.
There are two main surgical techniques for repairing a ruptured bicep tendon: the non-anatomic approach, where the torn bicep tendon is sewn back into the arm muscle, and the anatomic approach, which involves reattaching the torn tendon back onto the bone. Both techniques have their own advantages and are chosen based on the individual case.
The fixation technique for the tendon, which is how they reattach it, can be different as well. It can range from making tunnels in the bone to using various types of anchors or screws. The choice of technique will depend on various factors like the exact location of the rupture and the patient’s overall health condition.
In some cases, if the rupture is chronic (more than four weeks old), the risk of complications can be higher. In these scenarios, additional procedures like grafting, which involves using tissue from other parts of the body, may be recommended.
What else can Biceps Tendon Rupture be?
Diagnosing a rupture in the biceps tendon can be quite tricky. It’s important to remember that when injuries to the top part of the biceps tendon happen, they often occur at the same time as other shoulder problems, like issues with the rotator cuff and instability in the shoulder.
When diagnosing, it is also crucial to distinguish between this and other similar conditions such as:
- Rotator cuff disease
- Dislocated or unstable shoulder
- Impingement syndrome, which is a pinch in the shoulder
- A broken bone in the upper arm or elbow area
What to expect with Biceps Tendon Rupture
If the bicep muscle, located near your shoulder, gets ruptured, you typically recover well with non-surgical treatment without any long-term weakness in your shoulder or elbow. However, rupture of the bicep muscle close to the elbow (also called “distal”) can cause enduring pain and weakness when you try to rotate your forearm.
In cases of a complete rupture of the distal biceps, the tendon (the tough, flexible bands of fibrous tissue that connect muscles to bones) can significantly retract or pull back. If it becomes a chronic condition, repairing it later could be quite challenging technically. So, it’s very important to quickly diagnose a distal biceps rupture, especially in younger, more active individuals.
Possible Complications When Diagnosed with Biceps Tendon Rupture
The most common problem after an injury to the Lateral Antebrachial Cutaneous Nerve (LABCN), which is a nerve in your arm, is typically damage to this nerve. However, the most serious issue can be damage to the radial nerve or the posterior interosseous nerve, also in the arm.
Other complications may include a minor injury to the superficial radial nerve. Synostosis is another complication that may occur. This involves the development of a bridge of bone between two bones in your forearm, namely the radius and ulna. This can hinder or even eliminate your ability to rotate your forearm. This condition can occur if there is a fracture in the upper section of your radius bone caused by drilling a large tunnel or when a bone tunnel technique fails. Scientists have found methods, such as the dual incision technique, to reduce the occurrence of synostosis. In addition, it can be minimized in a single incision procedure by decreasing dissection between the radius and ulna and reducing exposure of the ulna’s outer layer.
Lastly, a problem known as heterotopic ossification, or the formation of bone in unusual places, may occur.
Complication Scenarios:
- Damage to the Lateral Antebrachial Cutaneous Nerve
- Severe damage to the radial nerve or the posterior interosseous nerve
- Minor injury to the superficial radial nerve
- Synostosis leading to rotation issues in the forearm
- Formation of bone in unusual areas (heterotopic ossification)
Recovery from Biceps Tendon Rupture
There are various recovery programs followed after a surgery to fix a torn biceps tendon. Usually, patients are advised to keep their arm bent at a 110-degree angle and turned slightly upwards — this is called flexion and moderate supination. It’s generally recommended to start gently moving the elbow by bending and turning during the early recovery phase after surgery. It’s also helpful to include strengthening exercises for the shoulder and wrist as part of the recovery plan after the operation.
