Course Of Musculocutaneous Nerve Research Articles

Morphological classification, anatomical variations, innervation patterns, musculocutaneous nerve relation of the coracobrachialis muscle: anatomical study and clinical significance.

The anatomical variations of coracobrachialis muscle (CBM) are of great clinical importance. This study aimed to elucidate the morphological variations, innervation patterns and musculocutaneous nerve (MCN) relation to CBM. Upper limbs of fifty cadavers (30 males and 20 females) were examined for proximal and distal attachments, innervation pattern of CBM and its relation to MCN. Four morphological types of CBM were identified according to number of its heads. The commonest type was the two-headed (63.0%) followed by the single belly (22.0%), three-headed (12.0%) and lastly fourheaded (3.0%) type. Moreover, an abnormal insertion of CBM was observed in four left limbs (4.0%); one inserting into the medial humeral epicondyle, the second into the upper third of humeral shaft, the third one in the common tendon of biceps, and the fourth one showing a bifurcated insertion. Also, four different innervation patterns of CBM were identified including MCN (80.0%), lateral cord (14.0%), lateral root of median nerve (4.0%), and median nerve itself (2.0%). The course of MCN was superficial to the single belly CBM (19.0%) and in-between the heads in the other types (71.0%). Measurements of the length and original distance of CBM muscular branches originating from MCN revealed no sex or side significant difference. Awareness of the anatomic variations, innervation patterns, and MCN relation of CBM is imperative in recent diagnostic and surgical procedures to obtain definite diagnosis, effective management and good outcome.

Accessory heads of biceps brachii muscle its embryogenesis and clinical implications: Cadaveric study.

Biceps brachii is an elongated two-headed fusiform muscle of the anterior compartment of the arm which crosses the shoulder as well as the elbow joint. It assists in flexion of the shoulder joint and elbow joint and powerful supinator of the forearm. It also assists in the abduction of the shoulder joint. Accessory heads of biceps brachii muscle not only give additional strength to the joints, at the same time, they may also simulate soft-tissue tumors that can result in neurovascular compression. Accordingly, the aim of this study was designed to evaluate the prevalence of accessory heads of biceps brachii muscle in human cadavers. This study was conducted on 107 formalin embalmed human cadavers (male 62 and 45 female), and dissections were performed in accordance with the institutional ethical standards and the Indian Anatomy Act. Out of 107 cadavers, three-headed biceps brachii was noted in 18 cadavers (16.82%) associated with the unusual course of musculocutaneous nerve. Rare and unusual unilateral five-headed biceps brachii was noted in one male cadaver (0.93%). All accessory heads noted in this study were supplied by the separate branches of musculocutaneous nerve except the humeral head of five-headed biceps, which was supplied by the radial nerve. Awareness of these anatomical variations, knowledge is necessary for radiologists, anesthetists, physiotherapists, and orthopedic surgeons to avoid complications during various radiodiagnostic procedures or surgeries of flexor deformities of the upper arm and forearm.

Bilateral variation in origin of thoracodorsal artery along with non-piercing variant of musculocutaneous nerve on left side

Subclavian artery continues as axillary artery in the axilla and is the principal source of blood supply of the lateral thoracic wall, axilla, scapular region, and upper limb. Thoracodorsal artery is one of the terminal branches of subscapular artery, which in turn is branch from the third part of axillary artery. Musculocutaneous nerve, a branch from lateral cord of brachial plexus, is the chief nerve supply of anterior compartment of arm, commonly seen piercing the coracobrachialis muscle before continuing as lateral cutaneous nerve of forearm. In the current case report, thoracodorsal arteries on both sides were arising from lateral thoracic artery, branch of second part of axillary artery and the left musculocutaneous nerve was not piercing the coracobrachialis muscles. Also, there was a communication between left musculocutaneous nerve and left median nerve. The knowledge about normal and variant pattern of origin and course of branches of axillary artery is very important as it may help the surgeons to identify the source of bleeding during surgeries in region of shoulder or axilla. Also, post-surgical complication or symptoms of nerve repair can be explained by the variation in course of musculocutaneous nerve and its communication with median nerve.

Study of variations in origin and course of musculocutaneous nerve

Study of variations in origin and course of musculocutaneous nerve

Unilateral abnormal course of musculocutaneous nerve and its communication with the median nerve

Unilateral abnormal course of musculocutaneous nerve and its communication with the median nerve

Variations in the course and branching pattern of musculocutaneous nerve

Abstract Background and aim: The variations in the course and communicating branches of musculocutaneous nerve is of clinical importance in the treatment of recurrent compression neuropathies and in the diagnosis of median nerve lesions. Most of the reports on anatomical variations of musculocutaneous nerve are single case studies and such studies with emphasis on gender difference in a sample of Keralite population are rarely reported. The objective of the present study is to observe the variations in the course of musculocutaneous nerve with special reference to communications with other nerves of the arm and to study the correlation between gender and variations of the nerve. Materials and Methods: Two hundred and sixty four arms were dissected in the department of Anatomy, Government medical college, Thrissur and studied for variations of muculocutaneous nerve. Analysis was done with epi info, using proportions, confidence interval and Chi Square test. The communications noted were classified using the available classifications of Le Minor, Venieratos and Anagnostopoulou and Choi et al. Results: Nerve variations were seen in 24.2 % cases which include, absence of the nerve (3.4%), nerve not piercing coracobrachialis (12.4%) and communication to median nerve (15.1 %). All the variations observed were statistically not significant. The embryological basis for the axonal pathfinding is considered as a result of both guidance molecules and electrical activity that change the calcium homeostasis within the growth cone to regulate growth cone turning. Conclusion: Variations that were observed in the present study may give sufficient and relevant data on the nerves, among Keralite population in which studies are few.