Abnormal musculotendinous slip from Biceps Brachii to Pronator Teres: A Case Report

Soumitra Trivedi,Manisha Barnwal Sinha,Dhyanesh Kumar Sharma,Mrithunjay Rathore,Abu Ubaida Siddiqui

doi:10.7439/ijbar.v6i1.1527

Soumitra Trivedi, Manisha Barnwal Sinha + Show 3 more

Open Access

https://doi.org/10.7439/ijbar.v6i1.1527

Copy DOI

Abstract

Variations of upper limb muscles are quite commonly seen during dissection. Biceps Brachii take an edge on this, as it commonly has two or more than two sites of origin and insertion, where mode of insertion being both aponeurotic as well as tendinous. In present study, apart from common modes of insertion, an additional musculotendinous slip was seen running from the medial side of the muscle belly of Biceps Brachii to Pronator Teres and Flexor Carpi Radialis deep to the aponeurosis. The functional aspect of such insertion is also questionable as Biceps brachii being a supinator is gaining attachment to a Pronator Muscle. Presence of such abnormal musculotendinous tissue can pose a difficult situation during surgical procedures in and around cubital fossa and can also be a cause of nerve entrapment syndromes. Additional muscular slip can lead to compression of neurovascular structure around that area.

Highlights

Variation encountered during dissection in the upper limb are quite common, they can be vascular, neural or muscular
Muscular variation is most commonly seen in Biceps Brachii muscle as it has two heads, long and short, originating from Supraglenoid tubercle and lateral side of the top of Coracoid process of Scapula respectively and two modes of insertion, tendinous insertion going to posterior surface of Radial Tuberosity and aponeurotic insertion going to Posterior border of ulna after mixing with deep fascia of the forearm[1]
Additional heads of Pronator Teres and Flexor Carpi Radialis have been described arising from Bicipital Aponeurosis[5]

Summary

1.Introduction

Variation encountered during dissection in the upper limb are quite common, they can be vascular, neural or muscular. Muscular variation is most commonly seen in Biceps Brachii muscle as it has two heads, long and short, originating from Supraglenoid tubercle and lateral side of the top of Coracoid process of Scapula respectively and two modes of insertion, tendinous insertion going to posterior surface of Radial Tuberosity and aponeurotic insertion going to Posterior border of ulna after mixing with deep fascia of the forearm[1]. Additional heads of Pronator Teres and Flexor Carpi Radialis have been described arising from Bicipital Aponeurosis[5]. The tendinous head was going normally to the Posterior part of Radial tuberosity but the aponeurotic part was totally replaced by a musculotendinous slip which was extending from the medial side of biceps belly and was gaining attachment on to the Pronator Teres as well as Flexor Carpi Radialis. Soumitra Trivedi et al / Abnormal musculotendinous slip from Biceps Brachii to Pronator Teres

3.Discussion

Conclusion