Distal Biceps Tears

The biceps muscle is the large muscle in the front of your upper arm. It helps you bend your elbow and rotate your forearm, so your palm faces upward (like when turning a doorknob) The distal biceps tendon is a strong cord-like structure that connects the lower part of your biceps muscle to the radius, one of the two bones in your forearm. This tendon allows your biceps to control movement in your elbow and forearm.

A distal biceps tendon tear happens when this tendon gets partially or completely torn. A partial tear means the tendon is still attached to the bone but is damaged. A complete tear means the tendon has fully detached from the bone. When this happens, the biceps muscle can no longer pull on the forearm properly, leading to pain, weakness, and loss of movement.

A distal biceps tear typically presents with sudden pain and noticeable changes in arm function. Symptoms include:

• Sharp pain at the front of the elbow: This occurs immediately after the injury and may be accompanied by a tearing sensation.
• Bruising and swelling: Discoloration may develop around the elbow and forearm due to internal bleeding from the torn tendon.
• Weakness in elbow flexion and forearm rotation: The ability to bend the elbow and rotate the forearm outward (such as turning a screwdriver) is significantly impaired.
• Visible deformity or “Popeye” muscle appearance: When the tendon ruptures completely, the biceps muscle retracts toward the upper arm, causing a noticeable bulge.
• Difficulty lifting or grasping objects: Strength loss can impact daily activities and athletic performance.

Distal biceps tendon tears typically occur when the elbow is forced to extend while the biceps is contracting. This commonly happens in activities that involve sudden or excessive force on the arm, such as lifting heavy weights, catching a falling object, or pulling against resistance. Athletes who participate in contact sports, weightlifting, or physically demanding occupations are at higher risk.

Several factors may increase susceptibility to a distal biceps tear, including:

• Overuse and repetitive strain: Repeated stress on the tendon over time can lead to gradual weakening.
• Sudden heavy load: A sharp increase in resistance, such as lifting a heavy object unexpectedly, can cause the tendon to rupture.
• Aging and degeneration: Tendons lose elasticity with age, making them more prone to injury, particularly in individuals over 40.
• Steroid use: The use of anabolic steroids has been associated with weakened tendon structures, increasing the likelihood of rupture.
• Smoking: Smoking can impair tendon health by reducing blood supply and delaying tissue repair.

Diagnosis begins with a thorough physical examination and medical history. Dr. Boden evaluates symptoms, range of motion, and strength in the affected arm. Specific tests, such as the Hook Test, are performed to assess the integrity of the distal biceps tendon.

In cases where a partial tear is suspected, imaging studies may be required:

• Ultrasound: A quick and effective tool for assessing tendon integrity.
• MRI (Magnetic Resonance Imaging): Provides detailed images of soft tissues and can confirm the extent of the tear, helping guide treatment decisions.