Fascial compartments of arm

Fascial Compartments of the Arm

The human arm is anatomically divided into various compartments, each enclosed by fascia. The fascial compartments of the arm are significant in both clinical and anatomical perspectives, as they contain and protect the muscles, nerves, and blood vessels. This article delves into the structure, contents, and clinical relevance of these compartments.

Structure and Contents

The arm, or brachium, is divided into two primary fascial compartments by the deep fascia: the anterior (flexor) compartment and the posterior (extensor) compartment. These compartments are separated by the lateral and medial intermuscular septa, which extend from the deep fascia to the humerus.

Anterior Compartment

The anterior compartment of the arm is also known as the flexor compartment. It primarily contains muscles that are involved in the flexion of the forearm at the elbow joint. The major muscles in this compartment include the biceps brachii, brachialis, and coracobrachialis. The anterior compartment is also traversed by the musculocutaneous nerve, which innervates the muscles within, and the brachial artery, which provides the blood supply.

Posterior Compartment

The posterior compartment of the arm, or extensor compartment, contains muscles that facilitate the extension of the forearm. The primary muscle in this compartment is the triceps brachii, along with the anconeus muscle. The radial nerve and the deep artery of the arm (profunda brachii) are the major neurovascular structures passing through this compartment.

Clinical Significance

The fascial compartments of the arm are of paramount importance in the clinical setting, particularly in the context of compartment syndrome. Compartment syndrome occurs when increased pressure within a closed fascial compartment compromises the circulation and function of the tissues within that space. This condition can be acute, often due to trauma or reperfusion injury, or chronic, as seen in exertional compartment syndrome.

Early diagnosis and treatment of compartment syndrome are critical to prevent permanent damage to the muscles and nerves. Clinically, it is characterized by pain, paresthesia, pallor, paralysis, and pulselessness (the five Ps). Treatment typically involves fasciotomy, a surgical procedure where the fascia is cut to relieve pressure.

Conclusion

Understanding the fascial compartments of the arm is crucial for healthcare professionals, especially those in orthopedics, emergency medicine, and surgery. Knowledge of these compartments aids in the diagnosis and management of various conditions, including compartment syndrome, and facilitates surgical approaches to the arm.