A three-headed biceps brachii muscle was found in one male cadaver out of 118 (0.85%) studied, both for educational and research purposes. The supernumerary head of the biceps brachii muscle was located superficially to the normal heads. It was originated from the insertion of the pectoralis major tendon at humerus. At the lower third of the arm, it was merging with the normal biceps brachii muscle and as a conjoint tendon was inserted at the radial tuberosity. The significance of our finding lies on the fact that the location of the supernumerary head was superficial to the other two heads, in contrast to previous reports in the literature. Surgeons and especially orthopaedic surgeons should bear in mind muscular variations like the one reported in the present study

Koebke, Juergen

Natsis, Konstantinos

Totlis, Trifon

Tsakotos, George

Vlasis, Konstantinos

English

Aristotle University of Thessaloniki: Open Journals / ΑΡΙΣΤΟΤΕΛΕΙΟ ΠΑΝΕΠΙΣΤΗΜΙΟ ΘΕΣΣΑΛΟΝΙΚΗΣ

IntroductIonAnatomical variations of the biceps brachii muscle are thought to be frequent, and may be revealed dur-ing clinical examination, autopsy or surgery. Biceps brachii is one of the most variable muscles of the hu-man body regarding its heads1. Studies from different ethnic groups have revealed the existence of super-numerary head of biceps brachii with different ratio between black, white or yellow race and different nationalities2,3. However, another study suggests that other factors, in addition to racial ones, might play a part in determining the incidence of the biceps brachii third head in a population4.Although the variations of the muscle’s insertion are uncommon, abnormalities regarding redundant heads of the muscle are relatively frequent5. The ex-istence of a third head is usually accompanied by variations in the musculocutaneous nerve6, abnormal course of blood vessels, co-existence of other multiple accessory muscles7 or diversities in adjacent muscles, namely coracobrachialis muscle8.The third head may originate from the coracoid process and humeral shaft, the tendon of pectoralis minor or pectoralis major, the insertion of deltoideus or coracobrachialis muscle, the greater tuberosity or the capsule of the shoulder joint9. The third head may be unilateral or bilateral5. The absence of the entire muscle or one of its heads, as well as the existence of a four-headed biceps brachii muscle, are rare10. Some-times the two heads are completely separated until their insertion.In the current study a cadaveric finding of a three-headed biceps brachii muscle is presented and its inci-dence and clinical significance are discussed.cASE PrESEntAtIonA three-headed biceps brachii muscle was found in the right arm of a 70 years old male cadaver out of 118 cadavers dissected for both educational and research A case of a supernumerary third head  of the biceps brachii muscle - clinical significance.Konstantinos Natsis1, Konstantinos Vlasis2, George Tsakotos2,  Trifon Totlis1,  Juergen Koebke31Laboratory of Anatomy, Medical School, Aristotle University of Thessaloniki2Laboratory of Anatomy, Medical School, University of Athens3Center of Anatomy, Medical School, University of CologneABStrAct: A three-headed biceps brachii muscle was found in one male cadaver out of 118 (0.85%) studied, both for educational and research purposes. The supernumerary head of the biceps brachii muscle was located superficially to the normal heads. It was originated from the insertion of the pectoralis major tendon at humerus. At the lower third of the arm, it was merging with the normal biceps brachii muscle and as a conjoint tendon was inserted at the radial tuberosity. The significance of our finding lies on the fact that the location of the supernumerary head was superficial to the other two heads, in contrast to previous reports in the literature. Surgeons and especially orthopaedic surgeons should bear in mind muscular variations like the one reported in the present study.Key Words: Arm, Muscles, Biceps brachii, Three heads.Corresponding author: Konstantinos Natsis, MD, PhD, Orthopaedic Surgeon, Associate Professor of Anatomy, Director of the Department of Anatomy, Medical School, Aristotle University of Thessaloniki, Postal Code: 541 24, P.O. Box: 300, Thessaloniki, Greece, Tel/Fax: +30 2310 999681, email: natsis@med.auth.gr40 Aristotle University Medical Journal, Vol. 37, Issue 2, June 2010purposes. Thus, the incidence of the three headed bi-ceps brachii muscle in our series was 0.85%.The supernumerary head was actually a flat mus-cular belly which originated from the insertion of the pectoralis major tendon at humerus. At the lower third of the arm, it was merging with the normal biceps brachii muscle and as a conjoint tendon was inserted into the radial tuberosity. Innervation of the third head was by the musculocutaneous nerve and the blood supply from brachial artery. There wasn’t any other anatomical variation concerning the afore-mentioned nerve and artery. The accessory head was not hyper-trophic and it was lying superficially to the normal ones. As a result, no sign of compression at nerves or vessels was observed (Figure 1).dIScuSSIonBiceps brachii is a long fusiform muscle which cov-ers the anterior aspect of the arm. It consists of two heads, the long one which originates from the labrum and the supraglenoid tubercle, and the short one which arises from the coracoid process. The two heads join together to form the muscle belly, which inserts in the radial tuberosity and the superomedial aspect of the bicipital aponeurosis. The main function of biceps is flexion and supination of the forearm. Innervation and vascular supply of the muscle is from the musculocu-taneous nerve and the brachial artery, respectively.The most frequent abnormality that has been re-ported in the literature regarding biceps brachii con-cerns the amount of muscle heads with a high preva-lence up to 22%1,10. However, bilateral occurrence of supernumerary heads of biceps brachii is relatively uncommon3. The most usual type of this variation is the three-headed one, although supernumerary bicipi-tal heads have been described as part of the three, four, five or even seven-headed biceps brachii.11 The inci-dence of the three-headed biceps brachii mucle was much lower in our series (0.85%) in comparison to the percentages reported in the literature.The significance of our finding lies on the fact that the location of the supernumerary head was superfi-cial to the other two heads, in contrast to previous re-ports in the literature12,13. Furthermore, it was crossing the anterior aspect of the elbow joint, augmenting the forearm’s muscle power at flexion and supination. Ad-ditional biomechanical and electromyographic studies might assist in clarifying the precise function of the variant. Moreover, we didn’t observe any accompa-nying anatomical abnormalities, regarding other mus-cles, nerves or vessels, which are very often in such cases of supernumerary head of biceps, according to the literature7.Surgeons and especially orthopaedic surgeons should bear in mind muscular variations like the one reported in the present study, since unusual clinical signs and symptoms at the upper limb could be attrib-uted to compression or entrapment of neurovascular bundles by these anatomical structures. Knowledge of these variations is necessary to avoid complications during surgical exposures14. Special attention is need-ed during the anterior exposure of the arm or shoul-der. Recognition and mobilization of the accessory bicipital head is necessary for adequate exposure of the shoulder joint through a deltopectoral incision15. Moreover, in humeral fractures, the supernumerary head may cause unusual displacement of the fracture ends due to the alteration of the biomechanical forces applied on the humerus.Figure 1. Right arm of the cadaver having a third head (*) of the biceps brachi muscle, located superficially to the short (SH) and long heads (LH) of the muscle. PM: Pecto-ralis major tendon. Three Headed Biceps Brachii Muscle 41  1. Bergman RA, Thompson SA, Afifi AK, Saadeh FA. Compendium of human anatomic variation. Balti-more: Urban and Schwarzenberg; 1988.  2. Asvat R, Candler P, Sarmiento EE. High incidence of the third head of biceps brachii in South African popu-lations. J Anat 1993;182(Pt 1):101-4.  3. Kosugi K, Shibata S, Yamashita H. Supernumerary head of biceps brachii and branching pattern of the musculocutaneus nerve in Japanese. Surg Radiol Anat 1992;14:175-85.  4. Santo Neto H,, Camilli JA,, Andrade JC, Meciano Filho J, Marques MJ. On the incidence of the biceps brachii third head in Brazilian white and blacks. Ann Anat 1998;180:69-71.  5. Swieter MG, Carmichael SW. Bilateral three-headed biceps muscles. Ann Anat 1980;148:346-9.  6. Oztürk NC, Uzmansel D, Oztürk H. An unreported pattern of musculocutaneous and median nerve com-munication with multiple variations of biceps brachii, a case report. Surg Radiol Anat 2010;Jan 5 [Epub ahead of print] DOI 10.1007/s00276-009-0616-6.  7. Vollala VR, Nagabhooshana S, Bhat SM, Potu BK, Rakesh V. Multiple accessory structures in the up-per limb of a single cadaver. Singapore Med J 2008;49:e254-8.  8. El-Naggar MM, Zahir FI. Two bellies of the coraco-brachialis muscle associated with a third head of the biceps brachii muscle. Clin Anat 2001;14:379-82.  9. Vijayabhaskar P, Baral P, Vaishya R, Shrestha RN. Su-pernumerary head of biceps brachii: a rare occurrence in the Nepalese population. Kathmandu Univ Med J 2008;6:225-7.10. Rodriguez-Niedenfuhr M, Vazquez T, Choi D, Par-kin I and Sanudo JR. Supernumerary humeral heads of the biceps brachii muscle revisited. Clin Anat 2003;16:197-203.11. Greig HW, Anson BJ and Budinger JM. Variations in the form and attachments of the biceps brachii muscle. Q Bull Northwest Univ Med Sch 1952;26:241-243.12. Cucca YY, McLay SV, Okamoto T, Ecker J, McMe-namin PG. The biceps brachii muscle and its distal insertion: observations of surgical and evolutionary relevance. Surg Radiol Anat 2009;Oct 22 [Epub ahead of print].13. Rodríguez-Vázquez JF, Mérida-Velasco JR, Jiménez-Collado J. Unusual variation of a third head of the bi-ceps brachii muscle. Ann Anat 1999;181:573-5.14. Kopuz C, Sancak B, Ozbenli S. On the incidence of third head of biceps brachii in Turkish neonates and adults. Kaibogaku Zasshi 1999;74:301-5.15. Warner JJ, Paletta GA, Warren RF. Accessory head of the biceps brachii. Case report demonstrating clinical relevance. Clin Orthop Relat Res. 1992;280:179-81.ΠΕΡΙΛΗΨΗ: Κατά τη διάρκεια ανατομικών παρασκευών 118 πτωμάτων, για διδακτικούς και ερευνητικούς σκοπούς, βρέθηκε σε ένα πτώμα ανδρός (0.85%) μία τρίτη μυϊκή κεφαλή του δικεφάλου βραχιονίου μυός. Η υπεράριθμη κεφαλή βρισκόταν επιπολής των δύο φυσιολογικών κεφαλών του μυός και εκφυόταν από τον καταφυτικό τένοντα του μείζονος θωρακικού μυός. Στο κάτω τριτημόριο του βραχίονα συγχωνευόταν με τις δύο φυσιολογικές κεφαλές του μυός, μαζί με τις οποίες καταφυόταν στο κερκιδικό όγκωμα, με κοινό τένοντα. Η περίπτωσή μας παρουσιάζει ενδιαφέρον λόγω της επιπολής εντόπισης της υπεράριθμης κεφαλής σε σχέση με τις δύο φυσιολογικές κεφαλές του δικεφάλου βραχιονίου μυός, σε αντί-θεση με τη βιβλιογραφία. Η γνώση της περιγραφείσας παραλλαγής είναι χρήσιμη για το χειρουργό και ιδιαίτερα για τον ορθοπαιδικό χειρουργό.Λέξεις Κλειδιά: Βραχίονας, Μύες, Δικέφαλος Βραχιόνιος, Τρίτη κεφαλή.Υπεράριθμη τρίτη κεφαλή του δικεφάλου βραχιονίου μυός.  Παρουσίαση περίπτωσης και κλινική σημασία.Κωνσταντίνος Νάτσης1, Κωνσταντίνος Βλάσης2, Γεώργιος Τσακωτός2,  Τρύφων Τότλης1, Juergen Koebke31Εργαστήριο Περιγραφικής Ανατομικής, Ιατρική Σχολή, Α.Π.Θ.2Εργαστήριο Περιγραφικής Ανατομικής, Ιατρική Σχολή, Ε.Κ.Π.Α.3Κέντρο Ανατομίας, Ιατρική Σχολή, Πανεπιστήμιο ΚολωνίαςrEFErEncES

A case of a supernumerary third head of the biceps brachii muscle - clinical significance

https://ejournals.lib.auth.gr/aumj/article/download/4713/4814

A case of a supernumerary third head of the biceps brachii muscle - clinical significance

Abstract

Similar works

Full text

Available Versions

Aristotle University of Thessaloniki: Open Journals / ΑΡΙΣΤΟΤΕΛΕΙΟ ΠΑΝΕΠΙΣΤΗΜΙΟ ΘΕΣΣΑΛΟΝΙΚΗΣ