Subluxation of the radius can produce radial nerve injury in the proximal forearm. The posterior interosseous syndrome typically occurs from compression of this division of the radial nerve as penetrates the supinator muscle within the proximal forearm. It is associated with repetitive supination of the forearm and hypertrophy of the supinator muscle. Isolated distal sensory radial neuropathy is associated with compression from handcuffs and tight bracelets. Occasionally, imaging of the elbow region or the humeral area is indicated to determine if any mass or bony lesions are compressing the nerve.
Therapy is dependent on the site and cause of the lesion.
When the lesion is due to external compression at the spiral groove, removing the source of the compression and conservative management is indicated. Physical therapy and wrist splinting aides in functional use of the hand. If the lesion is due to a humeral fracture, careful reduction and setting of the fracture must be performed to avoid further injury. This may require external fixation. If no recovery is noted within several months, then exploration for the site of compression or transection with possible surgical re-anastomosis may be indicated.