Targeted Nerve Implantation: Intramuscular Coaptation in a Denervated Motor Endplate Zone for Below and Above the Knee Amputations.

Post-amputation neuropathic pain, including symptomatic neuroma pain and phantom limb pain (PLP), remains a significant source of morbidity following lower limb amputation and can substantially impair prosthetic use and quality of life. Targeted muscle reinnervation (TMR) has demonstrated effectiveness in reducing these complications by providing transected nerves with physiologic motor targets; however, its application may be limited by recipient motor nerve caliber mismatch, inadequate target availability, or unfavorable anatomy. Regenerative peripheral nerve interface (RPNI) offers an alternative but requires free muscle graft harvest and is associated with increased operative complexity. Targeted nerve implantation (TNI) is a hybrid technique that implants a transected donor nerve directly into the zone of relative denervation near a native motor entry point without requiring motor nerve coaptation or free muscle grafting. We describe our surgical technique for TNI in above-knee and below-knee amputations, highlighting technical considerations and indications when standard TMR is not feasible. By utilizing denervated local muscle as a biologic target for axonal ingrowth, TNI preserves the physiologic principles of nerve regeneration while avoiding the limitations of both TMR and RPNI. TNI represents a practical adjunct for managing anatomical constraints encountered during amputation surgery. Further prospective studies are needed to evaluate postoperative pain, neuroma formation, phantom limb pain, prosthetic tolerance, and patient-reported functional outcomes.