Anatomical Relations
The medial intermuscular septum of the arm blends with the tendon of coracobrachialis and is continuous with the fascia of teres major on its lateral aspect. It is perforated by the ulnar nerve and the superior and inferior ulnar collateral arteries.
Related parts of the anatomy
Structure
The medial intermuscular septum extends from the lower part of the crest of the lesser tubercle of the humerus to the medial epicondyle, passing along the medial supracondylar ridge. The medial intermuscular septum is thicker than the lateral intermuscular septum.
Function
The medial and lateral intermuscular septum of the arm ensures the muscles are contained within anterior or posterior neuromuscular compartments. Each compartment house’s muscles of similar function and common innervation. Muscles in the anterior compartment of the arm are mainly flexors (biceps brachii, brachialis, and coracobrachialis), while muscles in the posterior compartment are mainly extensors (triceps brachii and anconeus). The fascial compartments of the upper limb are important clinically because they contain and direct the flow and spread of infection and hemorrhages in the limb.
The medial intermuscular septum of the arm provides additional muscle attachment for the triceps brachii posteriorly and the brachialis anteriorly (Standring, 2016).
References
Standring, S. (2016) Gray's Anatomy: The Anatomical Basis of Clinical Practice. Gray's Anatomy Series 41st edn.: Elsevier Limited.
