A distal biceps tendon rupture is the detachment of the biceps tendon from its insertion on the radial tuberosity at the elbow. The injury typically occurs from a single forceful eccentric contraction in a middle-aged man, produces visible deformity with weakness, and has time-sensitive treatment. Surgical repair within a few weeks of the injury produces the most reliable outcomes.
What Is a Distal Biceps Tendon Rupture?
The biceps muscle has two heads at the shoulder and a single tendon distally that inserts on the radial tuberosity, a small bony prominence on the radius near the elbow. The biceps flexes the elbow and rotates the forearm (supination). Of those two functions, supination power is disproportionately dependent on the distal biceps tendon, and its loss produces a characteristic supination weakness that is diagnostic.
Distal biceps rupture is usually a complete tear in which the tendon pulls off the radial tuberosity, often with the torn end retracting up the arm. Partial tears are less common but produce similar symptoms without the retraction. Once torn, the tendon does not heal back to bone on its own.
Causes and Risk Factors
- Eccentric overload of the biceps (catching a heavy falling object, forceful resistance during lifting)
- Weightlifting with heavy curls, particularly the heavy negative that loads the biceps eccentrically
- Middle-aged men are the dominant demographic (typically 40 to 60 years old)
- Anabolic steroid use, which is associated with higher tendon rupture rates
- Smoking and fluoroquinolone antibiotic use, both of which are associated with tendon degeneration
Symptoms
- A felt or heard pop at the elbow at the time of injury, often accompanied by sharp pain
- Bruising that appears over the anterior elbow and forearm within 24 to 48 hours
- A visible deformity in the upper arm (the Popeye sign) from the retracted muscle belly
- Weakness in elbow flexion and especially in supination (turning a screwdriver, turning a key)
- Pain may subside within a few days, but weakness persists
Diagnosis
Dr. Chudik’s evaluation includes the mechanism, timing, and clinical examination. Specific tests include the hook test, where the examiner attempts to hook a finger under the distal biceps tendon at the elbow; absence of the hook indicates a complete tear. X-rays are obtained to rule out associated bony injury. MRI confirms the diagnosis, characterizes partial versus complete tears, and documents retraction. The Westmont office has on-site high-field MRI and X-ray.
Treatment
Non-surgical treatment is reserved for patients who are not surgical candidates or who have low functional demands. It accepts permanent supination weakness of approximately 40 percent and flexion weakness of approximately 30 percent, along with a visible deformity.
For most active patients, surgical repair is recommended. Dr. Chudik performs distal biceps tendon repair, reattaching the torn tendon to the radial tuberosity with cortical button fixation, suture anchors, or a combination. Dr. Chudik also performs a tunnelless distal biceps repair technique he developed to avoid drilling bone tunnels across the radius, which carry a small risk of injury to nearby nerves and bone.
Timing matters. Acute repair within three to four weeks is technically simpler than delayed repair because the retracted tendon has not yet scarred in and can be pulled back to bone. Delayed repair may require a tendon graft to bridge the gap.
Recovery and Outcomes
Recovery after acute repair typically includes protected range of motion in a hinged brace for four to six weeks, progressive active motion and strengthening over two to three months, and return to full activity at four to six months. Return to heavy lifting is typically four months.
Outcomes after acute repair are very good, with restoration of most supination and flexion strength and resolution of the Popeye deformity. Delayed repair outcomes are less predictable.
When to See Dr. Chudik
Schedule an evaluation as soon as possible if you have felt a pop at the elbow with heavy lifting, if bruising has developed over the anterior elbow and forearm, or if you have sudden weakness turning your hand. Time matters for this injury. Call 630-324-0402 or request an appointment online.