Cheiralgia Paresthetica

Excerpt

The radial nerve is susceptible to compression at many different locations throughout its course. Cheiralgia paresthetic is compression of the superficial branch of the radial nerve in the forearm. This condition was first described by Dr. Wartenberg in 1932 when he introduced the term cheiralgia paresthetica and reported five clinical cases. It is also commonly known as Wartenburg syndrome and superficial radial nerve palsy. The superficial radial nerve is purely sensory and does not have any motor component. The condition presents with symptoms such as pain and burning located on the dorsal and radial side of the hand. Often it is aggravated by activities such as pronation, pinching, and gripping.

The radial nerve derives from the posterior cord of the brachial plexus and consists of fibers from the nerve roots at C5, C6, C7, C8, and sometimes T1. It descends between the long head of the triceps and axillary artery and enters the posterior compartment of the arm via the triangular interval. It continues to descend along the medial proximal upper arm between the long and medial head of the triceps until it reaches the spiral groove. The nerve passes distally and laterally around the posterior humerus, where it penetrates the lateral intermuscular septum and gains access to the anterior compartment of the brachium. The nerve enters the anterior compartment distal to the deltoid insertion at approximately 11 cm proximal to the elbow. It continues anteriorly to the lateral epicondyle between the brachialis and brachioradialis at the elbow to enter the forearm.

Roughly 3 to 5 cm proximal to the supinator, the radial nerve separates into the posterior interosseous nerve and the superficial branch of the radial nerve. The posterior interosseous nerve proceeds deep to the supinator. The superficial branch of the radial nerve continues superficially to the supinator and deep to the ulnar margin of the brachioradialis in the anterolateral aspect of the forearm to where it briefly runs alongside the radial artery. At roughly 9 cm proximal to the radial styloid process, it then pierces the deep fascia between the middle and distal third of the forearm, to emerge between the brachioradialis and extensor carpi radialis longus to eventually become subcutaneous. The superficial branch of the radial nerve then ramifies again at approximately 4.9 cm proximal to the styloid process into dorsomedial and dorsolateral branches. These branches travel alongside the cephalic vein and proceed across the first dorsal compartment of the wrist and its tendons, the abductor pollicis longus and the extensor pollicis brevis. The dorsolateral branch supplies the dorsolateral thumb proximal to the interphalangeal joint. The dorsomedial branch supplies the dorsomedial thumb proximal to the interphalangeal joint, dorsoradial half of the hand and dorsal aspect of the index, long, and radial half of ring fingers proximal to the distal interphalangeal joint.