Review Question - QID 218042

Distal biceps tendon repairs should be performed with the goal of repairing the tendon to the ulnar aspect of the bicipital tuberosity (Answer 4) to maximize supination strength.

Distal biceps tendon avulsion injuries are common injuries most often seen in middle-aged men. The mechanism of injury typically involves the eccentric loading of a flexed elbow. Patients often report a painful "pop" in the elbow followed by weakness most notably in supination. With appropriate physical examination (a positive hook test, biceps crease interval test, and passive forearm pronation), the diagnosis can consistently be made for complete distal biceps rupture. In the event of incomplete examination or partial ruptures, an MRI may be indicated. In young, healthy patients with complete tears, surgical repair is indicated to restore function. Multiple different fixation techniques and approaches exist, but all rely on repairing the distal biceps to the anatomic insertion on the bicipital tuberosity. Nonoperative management is reserved for older, low-demand patients or patients with partial ruptures.

Dunphy et al. performed a retrospective analysis of 784 primary distal biceps tendon repairs with different approaches and fixation methods. The authors found a higher rate of posterior interosseous nerve palsy and heterotopic ossification with a dual-incision technique. The most common complication was a lateral antebrachial cutaneous nerve palsy, regardless of the incision used, although the rate of palsy is higher with a single incision technique. The authors found no difference in re-rupture or infection rate in single vs dual incision techniques.

Mazzocca et al. performed a cadaveric study of 63 cadaveric elbows, evaluating four different repair techniques for biomechanical strength. Fixation with transosseous bone tunnels, suture anchor repair, suspensory cortical button, and interference screws were evaluated. The repairs were then tested for displacement and load to failure. The authors concluded that suspensory cortical button fixation provided the strongest repair technique with the largest load to failure. The authors also analyzed the anatomy of the bicipital tuberosity and distal biceps insertion and found that the insertion was reliably on the ulnar aspect of the tuberosity.

Amin et al. reviewed the complication rates of single-incision and dual-incision techniques for distal biceps fixation procedures. The authors performed a systematic review of 87 articles. They report a higher rate of re-rupture (2.5%) and nerve complications (9.8%) in single-incision techniques and a higher rate of heterotopic ossification (7%) in dual-incision techniques. The authors concluded that single-incision repair has a higher complication profile than dual-incision repair, mostly due to lateral antebrachial cutaneous nerve (LABCN) palsy.

Figure A shows an anatomic image of the right bicipital tuberosity with the highlighted area over the radial aspect of the tuberosity.

Incorrect Answers:
Answer 1: The use of a single-incision technique vs a two-incision technique has not been shown to have any increased effectiveness. The single-incision technique has been shown to increase the risk of LABCN injury, while two-incision technique increases the risk of radioulnar synostosis. Some authors argue that a dual-incision technique allows for better placement of fixation on the ulnar aspect of the tuberosity.
Answer 2: Moving the insertion site more distal would not be wise, as this would be outside of the bicipital tuberosity. The goal of repair is to insert fixation to the ulnar aspect of the bicipital tuberosity.
Answer 3: Biomechanical studies have shown that titanium button fixation has superior strength to suture anchors and interference screws.
Answer 5: Nonoperative management may be considered in patients with acute distal biceps injuries but is historically associated with a significant decrease in supination strength (up to 40% loss). This active, healthy patient emphasized the importance of supination for his job and should therefore be treated with repair.