HIGH ORIGIN OF THE THIRD DIGITAL BRANCH OF THE MEDIAN NERVE

Abstract

During a routine cadaveric dissection, we came across an anatomical variation at the level of the right forearm of a 77-year-old Caucasian male cadaver. Proximal to the superior border of the flexor retinaculum, we observed the median nerve giving a separate branch. It was the third common palmar digital nerve running distally from the ulnar side of the median nerve and coursing through the flexor digitorum superficialis muscle. In the distal part of the palm, it was divided into two proper palmar digital nerves for the adjacent sides of middle and ring fingers.

Keywords

• carpal tunnel
• entrapment neuropathy
• median nerve variations
• third common digital nerve

References

1. Kessler I. Unusual distribution of the median nerveat the wrist. Clin
2. Orthop Rel Res 1969;67:124–6.
3. Eiken O, Cartsman N, Eddeland A. Anomalous distal branching of the median nerve. Scan J Plast Reconstr Surg 1971;5:149–52.
4. Winkelman NZ, Spinner M. A variant high sensory branch of the median nerve to the third web space. Bull Hosp Joint Dis 1973;34: 161–6.
5. Lacoste P, Dalle M. Anomalie arterielle de l’avant-bras et de la main.
6. Essai d'interpretation embryologique. Comptes Rendus de Association des Anatomistes 1966;132:563–70.
7. Lanz U. Anatomical variations of the median nerve in the carpal tunnel. J Hand Surg Am 1977;2:44–53.
8. Chalmers J. Unusual causes of peripheral nerve compression. Hand 1978;10:168–75.

9. Kornberg M, Aulicino PL, DuPuy TE. Bifid median nerve with three thenar branches – case report. J Hand Surg Am 1983;8:583–4.
10. Fernandez-Garcia S, Pi-Folguera J, Estallo-Marino F. Bifid median nerve compression due to a musculotendinous anomaly of FDS to the middle finger. J Hand Surg Am 1994;19B:616–7.
11. Sundaram S, Kumar M, Sethupathy B, Nayak S, Krishnamurthy A. Split median nerve with variation in its common digital branch – a case report. Neuroanatomy 2008;7:15–6.
12. Natsis K, Karanassos MT, Papathanasiou E, Noussios G. A coexisting
13. anatomical variation of median and ulnar nerves in a cadaver palm. Folia Morphol (Warsz) 2012;71:269–74.
14. Natsis K, Paraskevas G, Piagkou M. An unusual origin and course of
15. multiple branches of the median nerve to the thenar muscles: a case report. Aristotle University Medical Journal 2013;40:41–4.
16. Barbe M, Bradfield J, Donathan M, Elmaleh J. Coexistence of multiple anomalies in the carpal tunnel. Clin Anat 2005;18:251–9.
17. Natsis K, Lordache G, Gigis I, Kyriazidou A., Lazaridis N, Noussios G, Paraskevas G. Persistent median artery in the carpal tunnel: anatomy, embryology, clinical significance, and review of the literature. Folia Morphol (Warsz) 2009;68:193–200.
18. Sañudo JR, Chikwe J, Evans SE. Anomalous median nerve associated
19. with persistent median artery. J Anat 1994;185(Pt 2):447–51.
20. Schultz RJ, Endler PM, Huddleston HD. Anomalous median nerve and an anomalous muscle belly of the first lumbrical associated with carpal-tunnel syndrome. J Bone Joint Surg Am 1973;55:1744–6.
21. Engineer NJ, Hazani R, Mowlavi A, Neumeister MW, Lee WP, Wilhelmi BJ. Variations in the anatomy of the third common digital nerve and landmarks to avoid injury to the third common digital nerve with carpal tunnel release. Eplasty 2008;8:e51.
22. Agarwal P, Gupta S, Yadav P, Sharma D. Cadaveric study of anatomical variations of the median nerve and persistent median artery at wrist. Indian J Plast Surg 2014;47:95–101.
23. Palmer AK, Toivonen DA. Complications of endoscopic and open
24. carpal tunnel release. J Hand Surg Am 1999;24:561–5.
25. Takami H, Takahashi S, Ando M. Bipartite median nerve with a double compartment within the transverse carpal canal. Arch Orthop Trauma Surg 2001;121:230–1.
26. Bayrak IK, Bayrak AO, Kale M, Turker H, Diren B. Bifid median
27. nerve in patients with carpal tunnel syndrome. J Ultrasound Med
28. ;27:1129–36.
29. Cavallo A V, Slattery PG, Barton RJ. Endoscopic carpal tunnel release
30. and congenital anomalies of the median nerve. Hand Surg 2003;8: 265–70.
31. Pierre-Jerome C, Smitson RD, Shah RK, Moncayo V, Abdelnoor M, Terk MR. MRI of the median nerve and median artery in the carpal tunnel: prevalence of their anatomical variations and clinical significance. Surg Radiol Anat 2010;32:315–22.
32. Duymus M, Yilmaz O, Ulasli AM, Asal N, Kosar U. Coexistence of trifid and bifid median nerve in a patient with bilateral carpal tunnel syndrome. Turk Neurosurg 2013;23:685–7.
33. Kasius KM, Claes F, Meulstee J, Verhagen WI. Bifid median nerve in
34. carpal tunnel syndrome: do we need to know? Muscle Nerve 2014; 50:835–43.