Snapshot A 39-year-old woman presents to her primary care physician's office due to pain and numbness in her hand. The patient reports that the pain is worse at night and when her hand is outstretched; to relieve the pain she shakes her hand or places it under warm running water. She says her symptoms mainly affect the first 3 digits of her hand. She denies any recent injury to or pain in the hand or neck. On physical exam, she has normal range of motion of the neck and arm. She has 2+ bilateral biceps, triceps, and brachioradialis reflexes. She has a positive Phalen and Tinel test. Introduction Clinical definition compressive median nerve neuropathy Epidemiology Demographics bimodal distribution 50-60 and 70-80 years of age Risk factors female gender obesity pregnancy hypothyroidism rheumatoid arthritis dialysis-related amyloidosis dialysisrelated amyloidosis repetitive use of the hand or wrist Etiology Increased pressure within the carpal tunnel Pathoanatomy normal anatomy the carpal tunnel contains digital flexor tendons flexor pollicis longus tendon median nerve pathology synovial noninflammatory fibrosis and thickening leads to median nerve compression (most common) compression leads to microvascular insufficiency causing ischemic damage to the nerve Presentation Symptoms pain or paresthesia in the median nerve distribution median nerve distribution the first 3 digits and radial half of 4th digit symptoms typically worse at night weakness or hand clumsiness Physical exam provoking tests Phalen test patients flexes palm at the wrist pain and/or paresthesia in the median nerve distribution is a positive test Tinel test percussion over the course of the median nerve pain and/or paresthesia in the median nerve distribution is a positive test Studies Making the diagnosis the diagnosis can be clinically made; however, it is confirmed by nerve conduction studies Nerve conduction studies indication may be used when contemplating surgical decompression Electromyogram indication typically used to exclude other etiologies such as polyneuropathy plexopathy radiculopathy Differential Cervical radiculopathy compressing C5-C6 distinguishing factor patients have neck pain, worsening symptoms with head movement, and pain radiation to the shoulders and arm patients also have reduced biceps, brachioradialis, and triceps reflex Treatment Conservative splinting indication to improve mild carpal tunnel syndrome symptoms Medical corticosteroid (oral or injection) indication to improve mild carpal tunnel syndrome symptoms Operative surgical decompression indication for severe median nerve injury reflected by nerve conduction studies (e.g., severe axonal degeneration) or needle electromyography Complications Rare Prognosis In mild-to-moderate cases, there is spontaneous resolution or response to conservative therapy