Median Nerve Compression in the Forearm: A Clinical Diagnosis.

Background: Median nerve entrapment in the forearm (MNEF) without motor paralysis is a challenging diagnosis. This retrospective study evaluated the clinical presentation, diagnostic studies, and outcomes following surgical decompression of MNEF. Methods: The study reviewed 147 patient medical charts following MNEF surgical decompression. With exclusion of patients with combined nerve entrapments (radial and ulnar), polyneuropathy, neurotmetic nerve injury, or median nerve motor palsy, the study sample included 27 patients. Data collected include: clinical presentation and pain, strength, provocative testing, functional outcomes, and Disabilities of the Arm, Shoulder and Hand (DASH) scores. Results: The study included 27 patients (mean follow-up = 7 months), and 13 patients had previous carpal tunnel release (CTR). Clinical presentation included pain (n = 27) (forearm, n = 22; median nerve innervated digits, n = 21; and palm, n = 21) and positive clinical tests (forearm scratch collapse test, n = 27; pain with compression over the flexor digitorum superficialis arch/pronator, n = 24; Tinel sign, n = 11). Positive electrodiagnostic studies were found for MNEF (n = 2) and carpal tunnel syndrome (n = 11). Primary CTR was performed in 10 patients and revision CTR in 7 patients. Postoperatively, there were significant (P < .05) improvements in strength, pain, quality of life, and DASH scores. Conclusions: The MNEF without motor paralysis is a clinical diagnosis supported by pain drawings, pain quality, and provocative tests. Patients with persistent forearm pain and median nerve symptoms (especially after CTR) should be evaluated for MNEF. Surgical decompression provides satisfactory outcomes.