Antebrachial – Anatomy, Function & Structure

‘Antebrachial’ is the anatomical word for ‘inner forearm.’ The medial antebrachial cutaneous nerve provides the sensory innervation of the medial forearm skin, superimposed by the olecranon.

Function And Structure

Together with the posterior and lateral antebrachial, the cutaneous nerves are responsible for the sensation of the skin of the forearm.

Antebrachial Region

The Antebrachial Region is classed as the ‘inner forearm.’

It emerges from the medial antebrachial cutaneous nerve through the brachial plexus and the sensory cell body between C8 and T1.

The medial antebrachial cutaneous nerve travels up the upper arm and runs along the brachial fascia to the basilic vein, approximately 10 cm proximally to the medial epicondyle.

When the nerve leaves the fascia, it splits into two large branches, front and back, and continues to the wrist. The spinal nerve (C5-T1) originating from the cervical and thoracic spine is rooted in the biceps and divides into a root-trunk division in the spinal cord that ends in a branch.

Cutaneous innervation of the upper extremity
Fig 1: Cutaneous innervation of the upper extremity

The medial antebrachial cutaneous nerve is one of the three non-terminal branches of the medial cord, which represents a continuation of the anterior division of the lower trunk of the brachial plexus itself.

The other two non-terminal branches are the medial brachial cutaneous nerve. The nerves ensure the sensory innervation of the medial arm and the medial mammary nerve, which ensures the motor innervation of the pectoralis major and minor.

The medial spinal cord is located in the superficial axillary artery, the veins, the axillary fossa, the median nerve, and the ulna nerve. The medial strand contributes fibers to the median nerve and continues to the ulna nerves.

It runs along the basilica until the elbow level, where it divides the elbow into volar and ulnar branches, which ensure sensory innervation of the medial forearm membrane and olecranon.

It then enters the brachial fascia, which lies above the brachial biceps and runs to the ulnar side of the brachial artery. On his way, he is accompanied by the basil vein, which crosses the triceps and brachial muscles.

The volar branch of the ramus volaris (anterior branch) is the largest and runs in front of the median vena cubiti, median and basilica.

Idealized distribution of the cutaneous innervation of the upper arm and forearm.
Fig 2: Idealized distribution of the upper arm and forearm cutaneous innervation.

It descends to the front of the ulna side of the forearm and distributes filaments through the wrist’s skin that communicate with the palmar cutaneous and ulna nerve.

The ulnar branch crosses the medial side of a basilica before a medial epicondyle at the back of the forearms. It descends from the rear to the ulnar side (wrist), spreading filaments over the skin.

It communicates with the medial brachial cutaneous, dorsal antebrachial, and cutaneous branches and the ulnar nerve’s radial and dorsal branches.

Compression of the lateral antebrachial cutaneous nerve in the biceps tendon occurs when the nerve leaves the point of the brachial fascia at the proximal elbow flexor fold.

Symptoms include pain in the anterolateral elbow, burning, and dysesthesia, which radiates to the lateral forearm when the forearm protons and the elbow is extended.

Lateral antebrachial sectional neuropathy is rare and is often overlooked in the case of elbow pain in throwing athletes.

Lateral Antebrachial Nerve Entrapment
Lateral Antebrachial Nerve Entrapment

Suppose the patient does not respond to non-surgical treatment. In that case, the surgical decompression of the nerve can result in complete relief of symptoms and a return to full activity if under local anesthetic.

The patient can also be treated with non-steroidal anti-inflammatory drugs, rest, activity modification, stretching, blocking, or splint.

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *