Introduction and objective:
Anconeus epitrochlearis (AE) is an anomalous accessory muscle discovered in 1865. It arises from the vmedial epicondyle of the humerus to the olecranon of the ulna. Its appearance is the result of evolution and has benefits as well as deficits that can be harmful. It is believed that if anconeus trochlearis is present, it replaces the Osborne’s ligament. The muscle is most commonly detected incidentally during the diagnosis of cubital tunnel aim of the study is to review papers on the prevalence of AE, symptoms resulting from its presence, and conclusions drawn from available sources on PubMed.

Review methods:
The review is based on 14 papers found in PubMed and PubMedCentral databases after searching for ‘anconeus epitrochlearis’, ‘anconeus epitrochlearis’ and ‘cubital tunnel syndrome’ published between 1874–2023.

Brief description of the state of knowledge:
Prevalence varies across different types of studies aimed at identifying anconeus epitrochlearis: 8.1%–23% for MRI studies, 4.5%–8.5% for operative reports, and 5.4%-26.5% for cadaveric studies. The mere presence of AE usually does not cause any symptoms. If the presence of anconeus epitrochlearis is symptomatic, patients complain of numbness in the fourth and fifth fingers of the hand and weakness of thenar muscle, which are symptoms of cubital tunnel syndrome (CuTS).

It is likely that AE alone does not cause cubital tunnel syndrome which occurs only when anconeus epitrochlearis undergoes hypertrophy, dispelling doubts about whether the mere presence of the muscle is synonymous with the development of cubital tunnel syndrome. A higher percentage of CuTS was reported in the dominant hand of individuals who had the AE in that limb. Cubital tunnel syndrome caused by the AE is a favourable factor for treatment and postoperative regeneration.

The authors extend their sincere thanks to Dr Magdalena Chmiel for creating the illustration for the review.
No external funding was received to perform this review.
Kwiecień M, Kuśnierz Ł, Daniluk A, Iwaniuk K, Buczek J, Białkowska Z, Samczuk M, Stachowicz H, Ostański J, Gawłowicz Ł. Anconeus epitrochlearis – prevalence and clinical manifestations. J Pre-Clin Clin Res. 2024; 18(1): 50–53. doi: 10.26444/jpccr/185686
Wilson TJ, Tubbs RS, Yang LJS. The anconeus epitrochlearis muscle may protect against the development of cubital tunnel syndrome: a preliminary study. J Neurosurg. 2016;125(6):1533–1538. doi:10.3171/2015.10.JNS151668.
Cammarata MJ, Hill JB, Sharma S. Ulnar Nerve Compression due to Anconeus Epitrochlearis: A Case Report and Review of the Literature. JBJS Case Connect. 2019;9(2):e0189. doi:10.2106/JBJS.CC.18.00189.
Duran S, Gunaydin E, Cayhan V. The prevalence of the anatomical variation in a Turkish population: supernumerary muscle-anconeus epitrochlearis. Surg Radiol Anat. 2022;44(10):1409–1415. doi:10.1007/ S00276–022–03021–7.
Suwannakhan A, Chaiyamoon A, Yammine K, et al. The prevalence of anconeus epitrochlearis muscle and Osborne’s ligament in cubital tunnel syndrome patients and healthy individuals: An anatomical study with meta-analysis. Surgeon. 2021;19(6):e402-e411. doi:10.1016/J. SURGE.2020.12.006.
Maslow JI, Johnson DJ, Block JJ, Lee DH, Desai MJ. Prevalence and Clinical Manifestations of the Anconeus Epitrochlearis and Cubital Tunnel Syndrome. Hand (N Y). 2020;15(1):69–74. doi:10.1177/1558944718789412.
Park IJ, Kim HM, Lee JY, et al. Cubital Tunnel Syndrome Caused by Anconeus Epitrochlearis Muscle. J Korean Neurosurg Soc. 2018;61(5):618–624. doi:10.3340/JKNS.2018.0033.
Nascimento SRR, Ruiz CR. A study on the prevalence of the anconeus epitrochlearis muscle by magnetic resonance imaging. Rev Bras Ortop (Sao Paulo). 2018;53(3):373–377. doi:10.1016/J.RBOE.2018.03.015.
Schertz M, Mutschler C, Masmejean E, Silvera J. High-resolution ultrasound in etiological evaluation of ulnar neuropathy at the elbow. Eur J Radiol. 2017;95:111–117. doi:10.1016/J.EJRAD.2017.08.003.
Husarik DB, Saupe N, Pfirrmann CWA, Jost B, Hodler J, Zanetti M. Elbow nerves: MR findings in 60 asymptomatic subjects–normal anatomy, variants, and pitfalls. Radiology. 2009;252(1):148–156. doi:10.1148/RADIOL.2521081614.
O’Driscoll SW, Horii E, Carmichael SW, Morrey BF. The cubital tunnel and ulnar neuropathy. J Bone Joint Surg Br. 1991;73(4):613–617. doi:10.1302/0301–620X.73B4.2071645.
Galton JC. On the Epitrochleo-Anconeus or Anconeus Sextus (Gruber). J Anat Physiol. 1874;9(Pt 1):168.2–175.
Zubair AS, Wang A, Roy B. Ulnar neuropathy from accessory epitrochlearis anconeus muscle. Neurol Sci. 2022;43(3):2165–2166. doi:10.1007/S10072–021–05713–1.
Kim N, Stehr R, Matloub HS, Sanger JR. Anconeus Epitrochlearis Muscle Associated With Cubital Tunnel Syndrome: A Case Series. Hand (N Y). 2019;14(4):477–482. doi:10.1177/1558944718762566.
Caliandro P, La Torre G, Padua R, Giannini F, Padua L. Treatment for ulnar neuropathy at the elbow. Cochrane Database Syst Rev. 2016;11(11):CD006839. doi: 10.1002/14651858.CD006839.pub4.
Journals System - logo
Scroll to top