Power-Optimizing Repair for Distal Biceps Tendon Rupture: Stronger and Safer

PURPOSE: Many approaches have been described to accomplish tendon reattachment to the radial tuberosity in a distal biceps tendon rupture, with significant success, but each is associated with potential postoperative complications, including posterior interosseous nerve (PIN) injury. To date, there has been no consensus on the best approach to the repair. The purpose of this study was to evaluate the supination strength and the distance of drill exit points from the PIN in a power-optimizing distal biceps repair method and compare the findings with those of a traditional anterior approach endobutton repair method. METHODS: Cadaveric arms were dissected to allow for distal biceps tendon excision from its anatomic footprint. Each arm was repaired twice, first with the power-optimizing repair using an anterior single-incision approach with an ulnar drilling angle and biceps tendon radial tuberosity wraparound anatomic footprint attachment, then with the traditional anterior endobutton repair. Following each repair, the arm was mounted on a custom-built testing apparatus, and the supination torque was measured from 3 orientations. The PIN was then located posteriorly, and its distance from each repair exit hole was measured. RESULTS: Five cadaveric arms, each with both the repairs, were included in the study. On average, the power-optimizing repair generated an 82%, 22%, and 13% greater supination torque than the traditional anterior endobutton repair in 45° supination, neutral, and 45° pronation orientations, respectively. On average, the power-optimizing repair produced drill hole exit points farther from the PIN (23 mm) than the traditional anterior endobutton repair (14 mm). CONCLUSIONS: The power-optimizing repair provides a significantly greater supination torque and produces a drill hole exit point significantly farther from the PIN than the traditional anterior endobutton approach. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic III.