Pronator Syndrome

Pronator syndrome (PS) is an uncommon proximal forearm compression neuropathy of the median nerve. Patients typically present with aching proximal forearm pain, numbness in the thumb/index finger/long finger/radial half of the ring finger, and numbness in the palm. PS is diagnosed by history and physical examination. Positive exam findings often include tenderness to palpation of the compressed nerve in volar proximal forearm, pain with resisted elbow flexion with the forearm in supination rotation, and pain with resisted forearm pronation with the elbow in extension. X-ray are typically ordered to rule out a supracondylar process (present in approximately 1% of the population). MRI, ultrasound and/or electrodiagnostic studies may be used to evaluate the nerve, but these tests can be inconclusive. When diagnosing PS, it is important to rule out distal compression of the median nerve (carpal tunnel syndrome), which has overlapping symptoms and is much more common.