Supercharge End-to-Side Anterior Interosseous Nerve to Ulnar Motor Nerve Transfer for Severe Ulnar Neuropathy: Two Cases Suggesting Recovery Secondary to Nerve Transfer

INTRODUCTION: The supercharged end-to-side (SETS) anterior interosseous nerve (AIN) to ulnar nerve transfer has been recently described for severe cubital tunnel syndrome. Previous studies have suggested that this technique augments or “babysits” the motor end plates until reinnervation occurs; however, it has more recently been suggested that reinnervation occurs by the donor nerve as evidenced in animal research. CASE REPORT: We present two cases of rapidly progressive ulnar neuropathy who underwent a SETS AIN to ulnar nerve transfer who demonstrated improvement in their electrodiagnostic studies in addition to improvement in their clinical and patient-reported outcome’s scores postoperatively. CONCLUSION: Our findings provide further evidence that previously demonstrated in the literature that the SETS does more than “babysit” the motor end plates, but that there is axonal growth along the new pathway.