Martin-Gruber Anastomosis
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This article may be too technical for most readers to understand.(September 2012) |
The Martin-Gruber Anastomosis (or Martin-Gruber Connection) is a communicating nerve branch between the median nerve and the ulnar nerve in the forearm. It is the most common anastomotic anomaly that occurs between these two nerves.[1] This connection carries motor nerve fibers. In cases of nerve lesions of the median or ulnar nerves the MGA can serve as a conduit for alternative innervation of portions of the forearm or hand. This inconstant pattern of connection can serve as explanation for a difficult or challenging differential diagnosis.[2] In one study,[3] the MGA was found in 22.9% of cadaver specimens. This relatively high incidence demonstrates the necessity for healthcare specialists to factor the MGA into their diagnoses.
Discussion:.[4] - motor nerve may cross over from the median to ulnar nerve in the forearm; (motor connections but not sensory connections); - it occurs in two patterns: - from median nerve in proximal forearm to ulnar nerve in middle to distal third of forearm, & from AIN to ulnar nerve; - other anastomoses between median nerve & ulnar nerve includes: - motor branch of median nerve to superficial head of FPB & ulnar nerve to the deep head of the FPB; - anastomosis, of median nerve & ulnar motor branches thru first lumbrical or thru innervation of & adductor pollicis; - branch of median nerve to third lumbrical joining neural branch to this muscle from deep branch of ulnar nerve; - median nerve may also form anastomoses w/ branch of radial nerve in vicinity of apb & have radial nerve innervate this muscle; - first dorsal interosseous, adductor pollicis, or even abductor digiti minimi may be innervated by the median nerve
References
- ^ Erdem HR, Ergun S, Erturk C, Ozel S (June 2002). "Electrophysiological Evaluation of the Incidence of Martin-Gruber Anastomosis in Healthy Subjects". Yonsei Medical Journal. 43 (3): 291–5. doi:10.3349/ymj.2002.43.3.291. PMID 12089734.
- ^ Unver Dogan, Nadire (March 14, 2009). "The communications between the ulnar and median nerves in upper limb" (PDF). neuroanatomy.org. Retrieved 2012-09-01.
- ^ Rodriguez-Niedenführ M, Vazquez T, Parkin I, Logan B, Sañudo JR (March 2002). "Martin-Gruber anastomosis revisited". Clinical Anatomy. 15 (2): 129–34. doi:10.1002/ca.1107. PMID 11877791.
- ^ "Martin Gruber Anastomosis".
- Standring, Susan (2008). Gray's Anatomy 40th ed. Elsevier. p. 854. ISBN 0443066841.