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A comprehensive review of motor innervation of the hand: variations and clinical significance

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Abstract

Purpose

The objective of the present review is to assemble the recognized anatomical variations, classifications, and clinical evidence with regard to innervation of the hand and discuss the clinical significance of these variations.

Methods

The material for this review was obtained by exploring PubMed and Google Scholar (search terms: hand innervation, variations of ulnar nerve, variations of median nerve, variations of radial nerve) as well as from standard anatomy texts. This initial search returned approximately 300 articles, which was reduced by abstract or title review. Reviewing the reference lists of significant papers uncovered further studies missed in the initial search. A few standard anatomy texts were also consulted for normal anatomy.

Results

The median and ulnar nerves frequently display a number of significant deviations from the traditionally taught branching patterns. The traditionally taught innervation of the hand is also found to be highly variable. This is especially evident with regard to the motor innervation of thenar muscles. These variations may be explained by the often under-recognized anastomoses that exist in the hand, such as the motor Riche–Cannieu Anastomosis. Some of these variations are associated significant clinical consequences.

Conclusions

The median and ulnar nerves display many anatomical variations, often with significant clinical implications. Awareness about these variations is clinically important when interpreting clinical examination findings, electrophysiological and radiological investigation as well as during management of patients in terms of surgical and anesthetic procedures.

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References

  1. Afroze MKH, Aswinpraksh, Ramesh P, Vaithianathan G, Galaji TK, Judson JP (2014) Variation in innervation of lumbricals of hands. IJIRD 3(5):243–246

  2. Ajmani ML (1996) Variations in the motor nerve supply of the thenar and hypothenar muscles of the hand. J Anat 189(Pt 1):145–150

    PubMed  PubMed Central  Google Scholar 

  3. Al-Qattan MM (2010) Variations in the course of the thenar motor branch of the Median Nerve and their relationship to the hypertrophic muscle overlying the transverse carpal ligament. J Hand Surg Am 35(11):1820–1824

    Article  PubMed  Google Scholar 

  4. Al-Qattan MM, Al-Zahrani KA, Al- Omawi M (2009) The Bifid median nerve re-visited. J Hand Surg Eur 34(2):212–214. doi:10.1177/1753193408089572

    Article  CAS  Google Scholar 

  5. Balogh B, Valencak J, Vesely M, Flammer M, Gruber H, Piza-Katzer H (1999) The nerve of Henle: an anatomic and immunohistochemical study. J Hand Surg Am 24(5):1103–1108

    Article  CAS  PubMed  Google Scholar 

  6. Bayrak IK, Bayrak AO, Kale M, Turker H, Diren B (2008) Bifid median nerve in patients with carpal tunnel syndrome. J Ultrasound Med 27(8):1129–1136

    Article  PubMed  Google Scholar 

  7. Belson P, Smith LK, Puentes J (1976) Motor innervation of the flexor pollicis brevis. Am J Phys Med 55(3):122–138

    CAS  PubMed  Google Scholar 

  8. Blair WF, Percival KJ, Morecraft R (1988) Distribution pattern of the deep branch of the Ulnar Nerve in the hypothenar eminence. Clin Orthop 229:294–301

    Google Scholar 

  9. Bolukbasi O, Turgut M, Akyol A (1999) Ulnar to median nerve anastomosis in the palm (Riches–Cannieu anastomosis). Neurosurg Rev 22:138–139

    Article  CAS  PubMed  Google Scholar 

  10. Bonnel F, Villa RM (1985) Anatomical study of the Ulnar Nerve in the hand. J Hand Surg 10:165–168

    Article  CAS  Google Scholar 

  11. Budak F, Gonenc Z (1999) Innervation anomalies in upper and lower extremities (an electrophysiological study). Electromyogr Clin Neurophysiol 39:231–234

    CAS  PubMed  Google Scholar 

  12. Caetano EB, Vieira LA, Caetano MF, Cavalheiro CS, Razuk M, Sabongi JJ (2016) Intramuscular Martin-Gruber Anastomosis. Acta Ortop Bras 24(2):94–97. doi:10.1590/1413-785220162402149097

    Article  PubMed  Google Scholar 

  13. Cavalheiro CS, Filho MR, Pedro G, Caetano MF, Vieira LA, Caetano EB (2016) Clinical repercussions of Martin-Gruber anastomosis: anatomical study. Rev Bras Ortop 51(2):214–223. doi:10.1016/j.rboe.2016.02.003

    Article  PubMed  PubMed Central  Google Scholar 

  14. Chang L, Blair WF (1985) The origin and innervation of the adductor pollicis muscle. J Anat 140(3):381–388

    PubMed  PubMed Central  Google Scholar 

  15. DaSilva MF, Moore DC, Weiss A-PC, Akelman E, Sikirica M (1996) Anatomy of the palmar cutaneous branch of the median nerve: clinical significance. J Hand Surg Am 21(4):639–643

    Article  CAS  PubMed  Google Scholar 

  16. Day MH, Napier JR (1961) The two heads of flexor pollicis brevis. J Anat 95:123–130

    CAS  PubMed  PubMed Central  Google Scholar 

  17. Demircay E, Civelek E, Cansever T, Kabatas S, Yilmaz C (2011) Anatomic variations of the median nerve in the carpal tunnel: a brief review of the literature. Turk Neurosurg 21(3):388–396

    PubMed  Google Scholar 

  18. Don Griot JP, Zuidam JM, van Kooten EO, Prose LP, Hage JJ (2000) Anatomic study of the ramus communicans between the ulnar and median nerves. J Hand Surg Am 25(5):948–954. doi:10.1053/jhsu.2000.16352

    Article  CAS  PubMed  Google Scholar 

  19. Engber WD, Gmeiner JG (1980) Palmer cutaneous branch of the ulnar nerve. J Hand Surg 5:26–29

    Article  CAS  Google Scholar 

  20. Felippe MM, Telles FL, Soares ACL, Felippe M (2012) Anastomosis between median nerve and ulnar nerve in the forearm. J Morphol Sci 29(1):23–26

  21. Ferrari GP, Gilbert A (1991) Superficial Anastomosis on the palm of the hand between the ulnar and median nerves. J Hand Surg Br 16B(4):511–514

    Article  Google Scholar 

  22. Forrest WJ (1967) Motor innervation of human thenar and hypothenar muscles in 25 hands: a study combining electromyography and percutaneous nerve stimulation. Can J Surg 10(2):196–199

    CAS  PubMed  Google Scholar 

  23. Ganes T (1992) Complete ulnar innervation of the thenar muscles combined with normal sensory fibres in a subject with no peripheral nerve lesion. Electromyogr Clin Neurophysiol 32:559–563

    CAS  PubMed  Google Scholar 

  24. Gonzalez MH, Brown A, Goodman D, Black B (1996) The deep branch of the Ulnar nerve in Guyon’s canal: branching and innervation of the hypothenar muscles. Orthop 19(1):55–58

    CAS  Google Scholar 

  25. Gozke E, Gurer R, Gurbuzer N (2012) Riche–Cannieu anastomosis: a case report. J Med Cases 3(3):195–196. doi:10.4021/jmc576w

    Google Scholar 

  26. Gruber W (1870) Ueber die Verbindung des Nervus medianus mit dem Nervus ulnaris am Unterame des Menschen um der Saugethiere. Arch Physiol 37:502–522

    Google Scholar 

  27. Gupta S, Michelsen-Jost H (2012) Anatomy and function of the thenar muscles. Hand Clin 28(1):1–7. doi:10.1016/j.hcl.2011.09.006

    Article  PubMed  Google Scholar 

  28. Harness D, Sekeles E (1971) The double anastomotic innervation of thenar muscles. J Anat 109(Pt 3):461–466

    CAS  PubMed  PubMed Central  Google Scholar 

  29. Henry BM, Zwinczewska H, Roy J, Vikse J, Ramakrishnan PK, Walocha JA, Tomaszewski KA (2015) The prevalence of anatomical variations of the median nerve in the Carpal tunnel: a systematic review and meta-analysis. PLoS One 10(8):e0136477. doi:10.1371/journal.pone.0136477

    Article  PubMed  PubMed Central  Google Scholar 

  30. Hur MS (2017) Variations of lumbrical muscle innervation patterns in the hand, focusing on the dual innervation of the third lumbrical muscle. Muscle Nerve 55(2):160–165

    Article  CAS  PubMed  Google Scholar 

  31. Kaplan EB, Smith RJ (1984) Kinesiology of the hand and wrist and muscular variations of the hand and forearm. In: Spinner M (ed) Kaplan’s functional and surgical anatomy of the hand, 3rd edn. J.B. Lippincott, Philadelphia, pp 283–349

    Google Scholar 

  32. Karl JW, Gancarczyk SM, Strauch RJ (2016) Complications of carpal tunnel release. Orthop Clin North Am 47(2):425–433

    Article  PubMed  Google Scholar 

  33. Kaur N, Kullar JS, Singla RK (2016) Variations in nerve supply of lumbricals of hand in north indian population. IJCAP 3(4):467–469

    Google Scholar 

  34. Kazakos KJ, Smyrnis A, Xarchas KC, Dimitrakopoulou A, Verettas DA (2005) Anastomosis between the median and Ulnar Nerve in the forearm. Acta Ortop Belg 71(1):29–35

    Google Scholar 

  35. Kimura I, Ayyar DR, Lippmann SM (1983) Electrophysiological verification of the ulnar to median nerve communications in the hand and forearm. Tohoku J Exp Med 141(3):269–274

    Article  CAS  PubMed  Google Scholar 

  36. Lanz U (1977) Anatomical variations of the Median nerve in the carpal tunnel. J Hand Surg 2(1):44–53

    Article  CAS  Google Scholar 

  37. Lauritzen RS, Szabo RM (1996) Innervation of the lumbricals muscles. J Hand Surg 21:57–58

    Article  CAS  Google Scholar 

  38. Lee KS, Oh CS, Chung IH, Sunwoo IN (2005) An anatomic study of the Martin-Gruber anastomosis: electrodiagnostic implications. Muscle Nerve 31(1):95–97

    Article  PubMed  Google Scholar 

  39. Leversedge FJ (2008) Anatomy and pathomechanics of the thumb. Hand Clin 28(4):681–684

    Google Scholar 

  40. Liss FE (2012) The interosseous muscles: the foundation of hand function. Hand Clin 28(1):9–12. doi:10.1016/j.hcl.2011.09.005

    Article  PubMed  Google Scholar 

  41. Littler JW (1949) Tendon transfers and arthrodesis in combined median and Ulnar nerve paralysis. J Bone Joint Surg 31(2):225–234

    Article  Google Scholar 

  42. Mannerfelt L (1966) Studies on the hand in ulnar nerve paralysis. A clinical-experimental investigation in normal and anomalous innervation. Acta Orthop Scand 37(sup87):3–176

    Article  Google Scholar 

  43. Marinacci A (1964) The problem of unusual anomalous innervation of hand muscles: the value of electrodiagnosis in its evaluation. Bull LA Neurol Soc 29:133–142

    CAS  Google Scholar 

  44. Martin CH, Seiler JG, Lesesne JS (1996) Cutaneous innervation of the palm: an anatomic study of the ulnar and median nerves. J of Hand Surgery 21(4):634–638

    Article  CAS  Google Scholar 

  45. Martin R (1763) Tal om Nervus allmanna Egenskaper Maniskans Kropp. Las Salvius, Stockholm

    Google Scholar 

  46. Matloub HS, Yan J-G, Mink Van Der Molen AB, Zhang L-L, Sanger JR (1998) The detailed anatomy of the palmar cutaneous nerves and its clinical implications. J Hand Surg Eur 23B(3):373–379

    Article  Google Scholar 

  47. McCabe SJ, Kleinert JM (1990) The nerve of Henle. J Hand Surg Am 15(5):784–788

    Article  CAS  PubMed  Google Scholar 

  48. Meenakshi-Sundaram S, Sundar B, Arunkumar M (2003) Marinacci communication: an electrophysiological study. Clin Neurophysiol 114(12):2334–2337

    Article  CAS  PubMed  Google Scholar 

  49. Moore KL, Dalley AF, Agur AMR (2014) Clinically oriented anatomy: international edition, 7th edn. Wolters Kluwer/Lippincott Williams & Wilkins, China

    Google Scholar 

  50. Murata K, Tamai M, Gupta A (2004) Anatomic study of variations of hypothenar muscles and arborization patterns of the ulnar nerve in the hand. J Hand Surg Am 29(3):500–509. doi:10.1016/j.jhsa.2004.01.006

    Article  PubMed  Google Scholar 

  51. Palti R, Vigler M (2012) Anatomy and function of lumbrical muscles. Hand Clin 28(1):13–17. doi:10.1016/j.hcl.2011.09.002

    Article  PubMed  Google Scholar 

  52. Paraskevas G, Ch Gekas C, Tzaveas A, Spyridakis I, Stoltidou A, Tsitsopoulos P (2008) Kaplan anastomosis of the Ulnar Nerve: a case report. J Med Case Rep 15(2):107

    Article  Google Scholar 

  53. Pasquella JA, Levine P (2012) Anatomy and function of the hypothenar muscles. Hand Clin 28(1):19–25. doi:10.1016/j.hcl.2011.09.003

    Article  PubMed  Google Scholar 

  54. Poisel S (1974) Ursprung und Verlauf des R. muscularis des Nervus digitalis palmaris communis I (N. medianus). Chir Praxis 18:471–474

    Google Scholar 

  55. Rovers JM, Brekelmans GJ, Visser LH (2013) Piso-hamate hiatus syndrome in a patient with Riche–Cannieu anastomosis. BMJ Case Rep. doi:10.1136/bcr-2013-008601

    PubMed  PubMed Central  Google Scholar 

  56. Rowntree T (1949) Anomalous innervation of the hand muscles. J Bone Joint Surg 31(4):505–510

    Article  Google Scholar 

  57. Sachs GM, Rayner EM, Shefner JM (1995) The all ulnar motor hand without forearm anastomosis. Muscle Nerve 18(3):309–313

    Article  CAS  PubMed  Google Scholar 

  58. Shu HS, Chantelot C, Oberlin C, Alnot JY, Shao H (1999) Martin-Gruber communicating branch: anatomical and histological study. Surg Radiol Anat 21(2):115–118

    Article  CAS  PubMed  Google Scholar 

  59. Sinnatamby CS (2011) Last’s anatomy, 12th edn. Churchill Livingstone Elsevier, China

    Google Scholar 

  60. Sraj SA, Moussallem CD, Stafford JB (2009) Cubital tunnel syndrome presenting with carpal tunnel symptoms: clinical evidence for sensory ulnar-to-Median Nerve communication. Am J Orthop 38(6):104–106

    Google Scholar 

  61. Stancic M, Micovic V, Potocnjak M (1999) The anatomy of the Berrettini branch: implications for carpal tunnel release. J Neurosurg 91:1027–1030

    Article  CAS  PubMed  Google Scholar 

  62. Stancic MF, Burgic N, Micovic V (2000) Marinacci communication: case report. J Neurosurg 92(5):860–862

    Article  CAS  PubMed  Google Scholar 

  63. Sulaiman S, Soames R, Lamb C (2015) The sensory distribution in the dorsum of the hand: anatomical study with clinical implications. Surg Radiol Anat 37(7):779–785. doi:10.1007/s00276-014-1416-1

    Article  PubMed  Google Scholar 

  64. Sulaiman S, Soames R, Lamb C (2015) Ulnar nerve cutaneous distribution in the palm: application to surgery of the hand. Clin Anat 28(8):1022–1028. doi:10.1002/ca.22626

    Article  PubMed  Google Scholar 

  65. Sunderland S, Ray LJ (1946) Metrical and non metrical features of the muscular branches of the Median Nerve. J Comp Neurol 85:191–201

    Article  CAS  PubMed  Google Scholar 

  66. Tagil SM, Bozkurt MC, Ozcakar L, Ersoy M, Tekdemir I, Elhan A (2007) Superficial palmar communications between the ulnar and median nerves in Turkish cadavers. Clin Anat 20(7):795–798. doi:10.1002/ca.20517

    Article  PubMed  Google Scholar 

  67. Uchida Y, Sugiok Y (1992) Electrodiagnosis of Martin-Gruber connection and its clinical importance in peripheral nerve surgery. J Hand Surg Am 17(1):54–59

    Article  CAS  PubMed  Google Scholar 

  68. Uncini A, Lange DJ, Lovelace RE (1988) Anomalous intrinsic hand muscle innervation in median and ulnar nerve lesions: an electrophysiological study. Ital J Neurol Sci 9(5):497–503

    Article  CAS  PubMed  Google Scholar 

  69. Wali A, Ahmed R, Khan S (2017) Electrophysiological evidence of the Riche–Cannieu anastomosis in the hand and its diagnostic implications; 2 case reports. Clin Neurophysiol 2:8–11. doi:10.1016/j.cnp.2016.11.001

    Google Scholar 

  70. Yang H, Gil Y, Kim S, Bang J, Choi H, Lee HY (2016) From the brachial plexus to the hand, multiple connections between the median and ulnar nerves may serve as bypass routes for nerve fibres. J Hand Surg Eur 41(6):648–656. doi:10.1177/1753193415622760

    Article  CAS  Google Scholar 

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  1. School of Medicine, Griffith University, Gold Coast, 4215, Australia

    Sacha Wynter & Lakal Dissabandara

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Correspondence to Lakal Dissabandara.

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Wynter, S., Dissabandara, L. A comprehensive review of motor innervation of the hand: variations and clinical significance. Surg Radiol Anat 40, 259–269 (2018). https://doi.org/10.1007/s00276-017-1898-8

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