Pronator teres syndrome is a compression neuropathy of the median nerve at the elbow. It is rare compared to compression at the wrist (carpal tunnel syndrome) or isolated injury of the anterior interosseous branch of the median nerve (anterior interosseous syndrome). Symptoms
Compression of the median nerve in the region of the elbow or proximal part of the forearm can cause pain and/or numbness in the distribution of the distal median nerve, and weakness of the muscles innervated by the anterior interosseous nerve: the flexor pollicis longus ("FPL"), the flexor digitorum profundus of the index finger ("FDP IF"), and the pronator quadratus ("PQ"). The pain tends to be at the wrist joint, in the distribution of the terminal branch of the anterior interosseous nerve, and is exacerbated by sustained pronation (i.e., wrist down). The weakness of the FPL and FDP IF is painless, but causes people to "drop things" and have a sense of loss of dexterity. Pinching with the wrist flexed magnifies the expression of this weakness, by reducing resting tension on the muscles of pinch. For instance, "child-proof" prescription pill bottles may be difficult to open.
This reflects involvement of the anterior interosseous nerve.Sensory changes may be found in the first three fingers as well as in the palm, indicating impairment of the median nerve proximal to the flexor retinaculum, but tend to involve the sensation of the entire hand going numb at night, with any pressure on the median nerve on the areas at the inside of the elbow.The clinical and electrophysiological features of pronator teres syndrome are quite different from patients with carpal tunnel syndrome or pure anterior interosseous syndrome, and are typically normal. Proper localisation is crucial to treatment options.Conduction velocity of the median nerve in the proximal forearm may be slow but the distal latency and sensory nerve action potential at the wrist are normal.Although MRI may show denervation atrophy of the affected muscles, its role in the evaluation of pronator teres syndrome is unclear.⁠
If the EMG or the MRI are abnormal for the pronator teres muscle and the flexor carpi radialis, this implies that the problem is at or proximal to the elbow, as the takeoff of the nerves to these muscles occurs proximal to the elbow. Treatment
Injection of corticosteroids into the pronator teres muscle may produce relief of symptoms.Massage therapy can also provide relief for individuals experiencing this condition.Surgical decompression can provide benefit in selected cases. References


== External links ==