A distal biceps tendon rupture is a significant injury involving the tearing of the tendon that connects the biceps muscle to the radius bone in the forearm. This injury typically occurs at the elbow, where the biceps tendon attaches to the radial tuberosity, a bony prominence on the radius. When this tendon ruptures, it usually detaches completely from the bone, leading to a loss of strength and function in the affected arm.

Causes:

Distal biceps tendon ruptures most commonly occur in middle-aged men and are often associated with a sudden and forceful contraction of the biceps muscle. This can happen during activities like lifting heavy objects, pulling motions, or sudden impacts where the elbow is forcibly straightened while the biceps is contracting. Risk factors include degenerative changes in the tendon due to aging, overuse, testosterone use, and repetitive strain, as well as underlying conditions like tendonitis, which can weaken the tendon over time.

Symptoms:

The symptoms of a distal biceps tendon rupture are usually acute and noticeable. They often include:

• Sudden Sharp Pain: A sharp, intense pain is felt in the front of the elbow, which may subside into a dull ache.

• Popping Sensation: Some individuals report hearing or feeling a pop at the time of injury.

• Weakness: Significant weakness in elbow flexion (bending the elbow) and supination (rotating the forearm to turn the palm upwards) is common.

• Bruising and Swelling: Bruising and swelling may develop around the elbow and forearm.

• Biceps Muscle Bulge: The biceps muscle may appear to bunch up near the shoulder (a "Popeye" deformity) due to the loss of tendon attachment at the elbow.

Diagnosis:

Diagnosis of a distal biceps tendon rupture is typically made through a combination of physical examination and imaging studies. During the physical exam, a healthcare provider may assess for the "hook test," where they attempt to hook their finger under the tendon at the elbow. If the tendon is ruptured, they won't be able to do so. Imaging studies such as an MRI or ultrasound can confirm the diagnosis and provide detailed information about the extent of the tear.

Treatment:

Treatment options depend on the patient's age, activity level, and the severity of the injury.

• Non-Surgical Treatment: In some cases, particularly for older or less active individuals, non-surgical treatment may be considered. This typically involves physical therapy to restore some arm function, but complete recovery of strength and function may be limited.

• Surgical Repair: Surgery is often recommended for active individuals or those who require minimizing strength loss in their arm. The procedure involves reattaching the tendon to the radius bone using sutures, anchors, or other fixation methods. Recovery usually involves a period of immobilization followed by physical therapy to regain strength and range of motion.

Prognosis:

With appropriate treatment, most patients recover well from a distal biceps tendon rupture. Surgical repair usually results in a good restoration of strength and function, though recovery can take several months. Non-surgical treatment may result in some loss of strength, particularly in activities involving heavy lifting or forearm rotation.