Anatomy of the Interosseus Arteries and Nerves

Arteries of the Forearm

• The posterior interosseus artery travels over the interosseous membrane and runs with the posterior interosseus nerve, a branch of the radial nerve.
• The anterior interosseus artery runs in front of the interosseous membrane with the anterior interosseus nerve, a branch of the median nerve.
• The radial artery travels from the cubital fossa down to the wrist between the brachioradialis and flexor carpi radialis tendons, where its pulse can be felt.

Cubital Fossa

• Forms the boundary between the arm and forearm.
• Also known as the antecubital fossa because it lies in front of the elbow.
• Triangular in shape with 3 borders, a roof, and a floor, with the apex inferiorly.

Nerves of the Forearm

• The radial nerve enters the forearm in the lateral region of the cubital fossa and splits into superficial and deep branches.
• The deep branch becomes the posterior interosseus nerve, while the superficial branch travels down towards the anatomical snuff box.
• The median nerve enters the cubital fossa medial to the brachial artery and then travels between the two heads of the pronator teres.

Neurological Examination

• Dr. Sumyra checked the C6 deep tendon reflex of the brachioradialis on the left side.
• The myotome responsible for elbow flexion is C5 and C6, while for elbow extension is C6 and C7.
• The arcade of Frohse is a likely site of nerve compression of the deep branch of the radial nerve.

Venous System of the Forearm

• The venous system comprises superficial and deep veins.
• The deep veins form a plexus that runs with the arteries.
• The major superficial veins include the basilic vein, cephalic vein, and median vein.

Compartment Syndrome

• A limb-threatening emergency that occurs when swelling of the area compresses the vessels and nerves in the region.
• The most common cause is fractures of the bones of the forearm.
• Signs and symptoms include pain out of proportion to exam findings, pallor, paresthesias, pulselessness, and paralysis (5Ps).
• The procedure of choice to relieve compartment syndrome is a fasciotomy.

Treatment and Management

• Dr. Azam designed a holistic treatment plan incorporating physical therapy, medications, and possible interventions, addressing not only the fracture but also the future strength of muscles, blood flow, and nerve health.