Diagnosis and management of common compression and entrapment neuropathies.

The most common focal neuropathies are carpal tunnel syndrome, ulnar neuropathy at the elbow, and peroneal neuropathy at the fibular head, but many other focal neuropathies, due to external compression or entrapment, may occur. Rational management depends on accurate localization; a thorough understanding of the basic anatomy, pathology, and pathophysiology helps in dealing with the vagaries of clinical presentation and electrodiagnostic evaluation. The differential diagnosis includes musculoskeletal conditions, plexopathies, radiculopathies, and occasionally, central nervous system dysfunction. Some focal neuropathies are an accentuation of a more generalized process, and a complex interplay of focal and diffuse pathology can arise.