Targeted Muscle Reinnervation in Amputation Pain Management

Targeted Muscle Reinnervation (TMR) has emerged as a dual-purpose technique that not only enhances myoelectric prosthesis control but also mitigates post-amputation neuropathic pain. By rerouting severed peripheral nerves into residual or denervated muscle targets, TMR promotes axonal regeneration within organised motor endplates, reducing aberrant nerve sprouting that underlies neuroma formation and phantom limb sensations. Clinically, TMR is applied at primary amputation or as a revision procedure to address symptomatic neuromas and persistent residual limb pain. Evidence indicates that TMR decreases the incidence and severity of phantom limb pain and residual limb pain, improves functional outcomes and quality of life, and offers a reproducible surgical protocol adaptable to upper and lower limb amputees. Integration of TMR into multidisciplinary pain management pathways underscores its global relevance, with ongoing innovation in surgical technique, patient selection and objective measures of neuromuscular integration driving refinements in both rehabilitative and neuroscientific domains.

Research from Nature Portfolio

Recent studies have highlighted persistent challenges and mechanistic insights in post-neuroma surgery. A long-term follow-up of individuals undergoing neuroma excision revealed that a majority continue to report pain on load, cold sensitivity and impaired daily activities despite surgical intervention, emphasising the need for adjunct procedures that redirect nerve regeneration rather than simply resecting neuromas. In parallel, experimental work in a rodent model has identified alpha smooth muscle actin (α-SMA) within neuroma tissue as closely correlated with spontaneous pain behaviours. Modulation of α-SMA expression altered pain marker levels and behavioural scores, suggesting that biomechanical tension within neuromas contributes directly to neuropathic pain. These findings underscore the importance of creating a regulated microenvironment for regenerating axons to prevent pathological fibrotic responses and support the development of targeted reinnervation approaches that combine mechanical off-loading with controlled guidance of nerve fibres.

Targeted Muscle Reinnervation in Amputation Pain Management publication trend

The graph below shows the total number of articles in targeted muscle reinnervation in amputation pain management across all publications each year (not limited to Nature Index journals).

Technical terms

Targeted Muscle Reinnervation (TMR): A surgical technique that transfers transected peripheral nerves into residual muscles to create new motor endplates, enhance prosthetic control and prevent neuroma formation.

Regenerative Peripheral Nerve Interface (RPNI): A method in which a small free muscle graft is implanted around a nerve stump to promote organised axonal reinnervation and reduce neuroma-associated pain.

Neuroma: A non-neoplastic, disorganised proliferation of nerve fibres and connective tissue at the site of nerve injury, often associated with neuropathic pain.

Residual Limb Pain (RLP): Pain perceived in the remaining segment of the limb following amputation, distinct from phantom sensations.

Phantom Limb Pain (PLP): Painful sensations perceived in the anatomical region of the amputated limb, arising from central and peripheral neural changes.

Alpha Smooth Muscle Actin (α-SMA): A cytoskeletal protein expressed by myofibroblasts; elevated levels in neuroma tissue are linked to mechanical tension and neuropathic pain.

References

1. Performance of Two Different Targeted Muscle Reinnervation Approaches for Improving Myoelectric Prosthetic Control. IEEE Transactions on Neural Systems and Rehabilitation Engineering (2025).
2. Neuromas cause severe residual problems at long-term despite surgery. Scientific Reports (2023).
3. Significance of alpha smooth muscle actin expression in traumatic painful neuromas: a pilot study in rats. Scientific Reports (2016).
4. Prevention is better than cure: Surgical methods for neuropathic pain prevention following amputation – A systematic review. Journal of Plastic Reconstructive & Aesthetic Surgery (2021).
5. Regenerative Peripheral Nerve Interfaces Effectively Prevent Neuroma Formation After Sciatic Nerve Transection in Rats. Frontiers in Molecular Neuroscience (2022).
6. Traumatic neuromas of peripheral nerves: Diagnosis, management and future perspectives. Frontiers in Neurology (2023).