Hereditary neuropathy with liability to pressure palsies is a disorder that affects peripheral nerves. These nerves connect the brain and spinal cord to muscles as well as sensory cells that detect touch, pain, and temperature. In people with this disorder, the peripheral nerves are unusually sensitive to pressure, which can cause recurrent episodes of numbness and loss of muscle strength (pressure palsies). Hereditary neuropathy with liability to pressure palsies causes episodes of numbness, tingling, and/or muscle weakness. An episode can last from several minutes to several months, but recovery is usually complete. Repeated incidents, however, can cause permanent weakness or loss of sensation. This disorder is also associated with painful limbs, especially the hands. In this disorder, a pressure palsy episode results from problems in a single nerve, but any peripheral nerve can be affected. Episodes often recur, but not always at the same site. The most common problem sites involve nerves in wrists, elbows, and knees. Fingers, shoulders, hands, feet, and the scalp can also be affected. Many people with this disorder experience carpal tunnel syndrome when a nerve in the wrist (median nerve) is involved. Carpal tunnel syndrome is characterized by numbness, tingling, and weakness in the hand and fingers. An episode in the hand may affect fine motor activities such as writing, opening jars, and fastening buttons. An episode in the leg can make walking, climbing stairs, or driving difficult or impossible. Symptoms usually begin during adolescence or early adulthood but may develop anytime from childhood to late adulthood. Symptoms vary in severity; many people never realize they have the disorder, while some experience prolonged disability. Hereditary neuropathy with liability to pressure palsies does not affect life expectancy.