Targeted Muscle Reinnervation in the Hand: A Technical Roadmap

  • Timothy P. Fowler
    Corresponding author: Timothy P. Fowler, MD, Department of Orthopedics and Rehabilitation, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242-1009.
    Department of Orthopedics and Rehabilitation, University of Iowa, Iowa City, IA
    Search for articles by this author


      Targeted muscle reinnervation (TMR) transfers cut the nerve endings to the motor nerves of the nearby muscles to reduce neuroma pain and/or enhance prosthetic function. To guide surgeons, anatomic “roadmaps” describe nerve transfer options for TMR at various locations. This study aimed to landmark and measure motor entry points (MEPs) to the hand interossei muscles in the context of TMR for digital nerve neuroma management.


      Ten fresh-frozen cadaveric hands were dissected to describe the innervation arising from the deep branch of the ulnar nerve to the dorsal interossei (DIs) and palmar interossei (PIs) muscles. The location of MEPs relative to the bone and soft tissue landmarks and the size of the target nerves were measured.


      The MEPs for the DIs and PIs were found in the central third of the metacarpal. The MEPs to the PIs averaged 23.3–24.7 mm from the median nerve. The length of nerve proximal to the MEP was limited, ranging between 6.5 ± 2.6 mm for the first PI and 10.5 ± 2.7 mm for the second PI. Similarly, minimal nerve proximal to the MEP of the DI was available for mobilization. Access to the first PI innervation required substantial release of the thenar musculature. Motor nerve diameter averaged 0.85–0.97 mm.


      In considering TMR for the management or prevention of digital nerve neuromas, the motor branches to the second and third PIs are the most accessible and best approached volarly, whereas motor branches to the DIs take more direct routes into the muscle, making volar exposure difficult. Nerve length proximal to the MEP is short, requiring that most of the nerve length for neurorrhaphy comes from the digital nerve. Size mismatch at the neurorrhaphy site is favorable compared to more proximal TMR.

      Clinical relevance

      Targeted muscle reinnervation in the hand is technically feasible for a patient with a symptomatic neuroma after digital amputation.

      Key words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Journal of Hand Surgery
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • van der Avoort D.J.
        • Hovius S.E.
        • Selles R.W.
        • van Neck J.W.
        • Coert J.H.
        The incidence of symptomatic neuroma in amputation and neurorrhaphy patients.
        J Plast Reconstr Aesthet Surg. 2013; 66: 1330-1334
        • Vlot M.A.
        • Wilkens S.C.
        • Chen N.C.
        • Eberlin K.R.
        Symptomatic neuroma following initial amputation for traumatic digital amputation.
        J Hand Surg Am. 2018; 43: 86.e1-86.e8
        • Guse D.M.
        • Moran S.L.
        Outcomes of the surgical treatment of peripheral neuromas of the hand and forearm: a 25-year comparative outcome study.
        Ann Plast Surg. 2013; 71: 654-658
        • Mass D.P.
        • Ciano M.C.
        • Tortosa R.
        • Newmeyer W.L.
        • Kilgore Jr., E.S.
        Treatment of painful hand neuromas by their transfer into bone.
        Plast Reconstr Surg. 1984; 74: 182-185
        • Hazari A.
        • Elliot D.
        Treatment of end-neuromas, neuromas-in-continuity and scarred nerves of the digits by proximal relocation.
        J Hand Surg Br. 2004; 29: 338-350
        • Koch H.
        • Haas F.
        • Hubmer M.
        • Rappl T.
        • Scharnagl E.
        Treatment of painful neuroma by resection and nerve stump transplantation into a vein.
        Ann Plast Surg. 2003; 51: 45-50
        • Koch H.
        • Herbert T.J.
        • Kleinert R.
        • Hubmer M.
        • Scharnagl E.
        • Pierer G.
        Influence of nerve stump transplantation into a vein on neuroma formation.
        Ann Plast Surg. 2003; 50: 354-360
        • Belcher H.J.
        • Pandya A.N.
        Centro-central union for the prevention of neuroma formation after finger amputation.
        J Hand Surg Br. 2000; 25: 154-159
        • Kon M.
        • Bloem J.J.
        The treatment of amputation neuromas in fingers with a centrocentral nerve union.
        Ann Plast Surg. 1987; 18: 506-510
        • Kim P.S.
        • Ko J.H.
        • O’Shaughnessy K.K.
        • Kuiken T.A.
        • Pohlmeyer E.A.
        • Dumanian G.A.
        The effects of targeted muscle reinnervation on neuromas in a rabbit rectus abdominis flap model.
        J Hand SurgAm. 2012; 37: 1609-1616
        • Dumanian G.A.
        • Potter B.K.
        • Mioton L.M.
        • et al.
        Targeted muscle reinnervation treats neuroma and phantom pain in major limb amputees: a randomized clinical trial.
        Ann Surg. 2019; 270: 238-246
        • Kuiken T.A.
        • Barlow A.K.
        • Hargrove L.
        • Dumanian G.A.
        Targeted muscle reinnervation for the upper and lower extremity.
        Tech Orthop. 2017; 32: 109-116
        • Souza J.M.
        • Cheesborough J.E.
        • Ko J.H.
        • Cho M.S.
        • Kuiken T.A.
        • Dumanian G.A.
        Targeted muscle reinnervation: a novel approach to postamputation neuroma pain.
        Clin Orthop Relat Res. 2014; 472: 2984-2990
        • Daugherty T.H.F.
        • Bueno Jr., R.A.
        • Neumeister M.W.
        Novel use of targeted muscle reinnervation in the hand for treatment of recurrent symptomatic neuromas following digit amputations.
        Plast Reconstr Surg Glob Open. 2019; 7e2376
        • Elmaraghi S.
        • Albano N.J.
        • Israel J.S.
        • Michelotti B.F.
        Targeted muscle reinnervation in the hand: treatment and prevention of pain after ray amputation.
        J Hand SurgAm. 2020; 45: 884.e1-884.e6
        • Daugherty T.H.F.
        • Mailey B.A.
        • Bueno Jr., R.A.
        • Neumeister M.W.
        Targeted muscle reinnervation in the hand: an anatomical feasibility study for neuroma treatment and prevention.
        J Hand Surg Am. 2020; 45: 802-812
        • Kuiken T.A.
        • Dumanian G.A.
        • Lipschutz R.D.
        • Miller L.A.
        • Stubblefield K.A.
        The use of targeted muscle reinnervation for improved myoelectric prosthesis control in a bilateral shoulder disarticulation amputee.
        Prosthet Orthot Int. 2004; 28: 245-253
        • Bowen J.B.
        • Ruter D.
        • Wee C.
        • West J.
        • Valerio I.L.
        Targeted muscle reinnervation technique in below-knee amputation.
        Plast Reconstr Surg. 2019; 143: 309-312
        • Fracol M.E.
        • Janes L.E.
        • Ko J.H.
        • Dumanian G.A.
        Targeted muscle reinnervation in the lower leg: an anatomical study.
        Plast Reconstr Surg. 2018; 142: 541e-550e
        • Gart M.S.
        • Souza J.M.
        • Dumanian G.A.
        Targeted muscle reinnervation in the upper extremity amputee: a technical roadmap.
        J Hand Surg Am. 2015; 40: 1877-1888
        • Hughes L.A.
        • Clarke H.M.
        Normal arborization of the deep branch of the ulnar nerve into the interossei and lumbricals.
        J Hand Surg Am. 1995; 20: 10-14
        • Bonnel F.
        • Vila R.M.
        Anatomical study of the ulnar nerve in the hand.
        J Hand Surg Br. 1985; 10: 165-168
        • Dodds III, G.A.
        • Hale D.
        • Jackson W.T.
        Incidence of anatomic variants in Guyon's canal.
        J Hand Surg Am. 1990; 15: 352-355
        • Gross M.S.
        • Gelberman R.H.
        The anatomy of the distal ulnar tunnel.
        Clin Orthop Relat Res. 1985; 196: 238-247
        • König P.S.
        • Hage J.J.
        • Bloem J.J.
        • Prosé L.P.
        Variations of the ulnar nerve and ulnar artery in Guyon’s canal: a cadaveric study.
        J Hand Surg Am. 1994; 19: 617-622
        • Lindsey J.T.
        • Watumull D.
        Anatomic study of the ulnar nerve and related vascular anatomy at Guyon’s canal: a practical classification system.
        J Hand Surg Am. 1996; 21: 626-633
        • Blair W.F.
        • Percival K.J.
        • Morecraft R.
        Distribution pattern of the deep branch of the ulnar nerve in the hypothenar eminence.
        Clin Orthop Relat Res. 1988; 229: 294-301
        • Murata K.
        • Tamai M.
        • Gupta A.
        Anatomic study of variations of hypothenar muscles and arborization patterns of the ulnar nerve in the hand.
        J Hand Surg Am. 2004; 29: 500-509