The utility of botulinum toxin A in the repair of distal biceps tendon ruptures

Purpose The purpose of our study is to report the outcomes and complications in patients who underwent distal biceps tendon repair with the use of Botulinum toxin A (BoNT-A) as an adjunct to surgery. Methods A retrospective review of 14 patients who underwent 15 distal biceps tendon repairs was performed. All repaired tendons had their correlating muscle bellies injected intraoperatively with a mixture of 100U of BoNT-A and 10 ml of normal saline. Each patient was evaluated for surgical and post-operative complications and followed with Disabilities of the Arm, Shoulder and Hand (DASH) Disability Scores. Results The cohort was exclusively male, 14/14 (100%). The mean age at procedure was 52.1 years (range: 29–65 years). Types of injuries repaired included: 12 acute biceps tendon ruptures, one chronic partial (> 50% of tendon) biceps tear, and two chronic biceps ruptures. Average final follow-up was 32.9 months (SD: 19.6; range: 7.07–61.72). Average time to repair of chronic injury was 5.75 months (range: 2–12 months). There were no intraoperative complications, and all patients were discharged home on the day of surgery. Average DASH score at latest follow-up was 4.9 (range: 0.0–12.5). All patients had return of function of paralyzed muscle prior to final follow-up. One patient required an incision and drainage for a deep infection 1 week post-operatively, without any further complications. Another patient required operative removal of heterotopic ossification located around the tendon fixation site, which was the result of a superficial infection treated with antibiotics 2 weeks post-operatively. This patient later healed with improvement in supination/pronation range-of-motion and no further complications. Conclusions Injection of BoNT-A is safe and effective to protect distal biceps tendon repair during the early phases of bone-tendon healing. Clinical relevance BoNT-A may is safe and effective to protect distal biceps tendon repair. The utility of BoNT-A as an adjunct to surgical repair may be applicable to acute or chronic tears as well as repairs in the non-compliant patient without decreases in functional scores after return of function of the biceps muscle. Level of evidence Level 4.