open access
The ulnar nerve in the cubital tunnel: a foetal study
- Department of Clinical Anatomy, School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban, South Africa
- Department of Human Anatomy and Physiology, Faculty of Health Sciences, University of Johannesburg, Doornfontein Campus, South Africa
open access
Abstract
Background: The ulnar nerve (UN), a terminal branch of the medial cord of the brachial plexus, is located posteromedial to brachial artery coursing along medially in the arm from the anterior to the posterior compartment through the arcade of Struthers. It passes posterior to medial epicondyle of humerus and enters the cubital tunnel. Then, it exits through the distal part of the cubital fossa to enter the medial side of the forearm between the two heads of the flexor carpi ulnaris muscle underneath Osborne’s ligament to enter the anterior compartment of the forearm. Entrapment of the UN at the cubital tunnel results in a pain and a tingling sensation on the medial side of the forearm and fourth and fifth digits.
Materials and methods: This foetal study documented the course of the UN within the cubital tunnel and its anatomical relations utilising bilateral microscopic dissection of 25 foetuses (gestational age: 19–36 weeks).
Results: The UN followed the standard anatomical course in 96% (48/50) of the specimens, however it was found to lie deep to the muscles of the cubital tunnel in 6% (3/50). The radial artery joined the UN distal to the cubital tunnel in 8% (4/50), while the superior ulnar collateral artery was posteriorly related to the UN in 32% (16/50) of specimens. The Osborne’s ligament (crossed between the two heads of the flexor carpi ulnaris muscle, posterior to the medial epicondyle of the humerus) was present in all specimens 100% (50/50). It had a mean length of 6.32 ± 0.97 mm and 6.30 ± 1.10 mm on the left and right sides, respectively. The current study observed that the flexor pronator aponeurosis was present in 2% (1/50) of specimens.
Conclusions: Knowledge of the normal and variable anatomical course of the UN in the cubital tunnel in this study may assist in the diagnosis and treatment of compressive neuropathy of the UN in the cubital tunnel.
Abstract
Background: The ulnar nerve (UN), a terminal branch of the medial cord of the brachial plexus, is located posteromedial to brachial artery coursing along medially in the arm from the anterior to the posterior compartment through the arcade of Struthers. It passes posterior to medial epicondyle of humerus and enters the cubital tunnel. Then, it exits through the distal part of the cubital fossa to enter the medial side of the forearm between the two heads of the flexor carpi ulnaris muscle underneath Osborne’s ligament to enter the anterior compartment of the forearm. Entrapment of the UN at the cubital tunnel results in a pain and a tingling sensation on the medial side of the forearm and fourth and fifth digits.
Materials and methods: This foetal study documented the course of the UN within the cubital tunnel and its anatomical relations utilising bilateral microscopic dissection of 25 foetuses (gestational age: 19–36 weeks).
Results: The UN followed the standard anatomical course in 96% (48/50) of the specimens, however it was found to lie deep to the muscles of the cubital tunnel in 6% (3/50). The radial artery joined the UN distal to the cubital tunnel in 8% (4/50), while the superior ulnar collateral artery was posteriorly related to the UN in 32% (16/50) of specimens. The Osborne’s ligament (crossed between the two heads of the flexor carpi ulnaris muscle, posterior to the medial epicondyle of the humerus) was present in all specimens 100% (50/50). It had a mean length of 6.32 ± 0.97 mm and 6.30 ± 1.10 mm on the left and right sides, respectively. The current study observed that the flexor pronator aponeurosis was present in 2% (1/50) of specimens.
Conclusions: Knowledge of the normal and variable anatomical course of the UN in the cubital tunnel in this study may assist in the diagnosis and treatment of compressive neuropathy of the UN in the cubital tunnel.
Keywords
ulnar nerve, cubital fossa, foetal study and anatomical course
Title
The ulnar nerve in the cubital tunnel: a foetal study
Journal
Issue
Article type
Original article
Pages
31-36
Published online
2020-12-30
Page views
6326
Article views/downloads
1393
DOI
Pubmed
Bibliographic record
Folia Morphol 2022;81(1):31-36.
Keywords
ulnar nerve
cubital fossa
foetal study and anatomical course
Authors
D. N. Bailey
S. Ishwarkumar
B. Z. De Gama
P. Pillay
- Amadio P, Beckenbaugh R. Entrapment of the ulnar nerve by the deep flexorpronator aponeurosis. J Hand Surg. 1986; 11(1): 83–87.
- Assmus H, Antoniadis G, Bischoff C. Carpal and cubital tunnel and other, rarer nerve compression syndromes. Dtsch Arztebl Int. 2015; 112(1-2): 14–25; quiz 26.
- Bartels RH, Grotenhuis JA, Kauer JMG. The arcade of Struthers: an anatomical study. Acta Neurochir (Wien). 2003; 145(4): 295–300; discussion 300.
- Becker R, Manna B. Anatomy, upper limb, elbow, nerves, ulnar. StatPearls Publishing, Treasure Island (FL) 2018.
- Caetano EB, Sabongi Neto JJ, Vieira LA, et al. The arcade of Struthers: an anatomical study and clinical implications. Rev Bras Ortop. 2017; 52(3): 331–336.
- Cutts S. Cubital tunnel syndrome. Postgrad Med J. 2007; 83(975): 28–31.
- Degeorges R, Masquelet AC. The cubital tunnel: anatomical study of its distal part. Surg Radiol Anat. 2002; 24(3-4): 169–176.
- Depukat P, Mizia E, Zwinczewska H, et al. Topography of ulnar nerve and its variations with special respect to carpal region. Folia Med Cracov. 2014; 54(4): 45–58.
- Gonzalez MH, Lotfi P, Bendre A, et al. The ulnar nerve at the elbow and its local branching: an anatomic study. J Hand Surg Br. 2001; 26(2): 142–144.
- Granger A, Sardi JP, Iwanaga J, et al. Osborne's ligament: a review of its history, anatomy, and surgical importance. Cureus. 2017; 9(3): e1080.
- Green JR, Rayan GM. The cubital tunnel: anatomic, histologic, and biomechanical study. J Shoulder Elbow Surg. 1999; 8(5): 466–470.
- Heithoff SJ. Cubital tunnel syndrome: ulnar nerve subluxation. J Hand Surg Am. 2010; 35(9): 1556; author reply 1556–7.
- Inserra S, Spinner M. An anatomic factor significant in transposition of the ulnar nerve. J Hand Surg. 1986; 11(1): 80–82.
- Joshi SD, Joshi SS. Study of cubital tunnel. J Anat Soc India. 2002; 51(2): 173–175.
- Macchi V, Tiengo C, Porzionato A, et al. The cubital tunnel: a radiologic and histotopographic study. J Anat. 2014; 225(2): 262–269.
- Mizia E, Zarzecki MP, Pekala JR, et al. An anatomical investigation of rare upper limb neuropathies due to the Struthers' ligament or arcade: a meta-analysis. Folia Morphol. 2021; 80(2): 255–266.
- Moore KL. Clinically Oriented Anatomy 6th Ed. Lippincott, Williams and Wilkins, Baltimore, MD 2010: 770.
- Moore KL, Dalley AF, Agur AMR. Clinically orientated anatomy. Lippincott, Williams and Wilkins 2014: 514–516.
- Sawardeker P, Kindt KE, Baratz NE. Nerve Compression: Ulnar Nerve of the Elbow. 2015.
- Siemionow M, Agaoglu G, Hoffmann R. Anatomic characteristics of a fascia and its bands overlying the ulnar nerve in the proximal forearm: a cadaver study. J Hand Surg Eur Vol. 2007; 32(3): 302–307.
- Standring S. Gray's Anatomy E-Book: The Anatomical Basis of Clinical Practice. Elsevier Health Sciences 2015.
- Xarchas KC, Psillakis I, Koukou O, et al. Ulnar nerve dislocation at the elbow: review of the literature and report of three cases. Open Orthop J. 2007; 1: 1–3.
- Yamada K, Nagaoka M, Nagao S, et al. Anatomical study of osborne ligament elongation in relation to elbow flexion. J Nihon University Med Ass. 2013; 72(3): 154–158.