Carpal Tunnel Syndrome (CTS) is the most common compressive neuropathy of the upper extremity. The cause is usually unknown but it can be associated with certain medical conditions (diabetes, thyroid disease) or previous trauma (wrist fractures or ligament injuries). Genetics is increasingly believed to play a role as well. Contrary to popular belief, there is no evidence that "repetitive motion" causes CTS — a myth that is particularly difficult to dispel, especially since patients often are more aware of their symptoms when they perform those activities.
Symptoms will classically consist of a sense that the hand is falling asleep, most often at night but sometimes during the day, especially with activities such as driving, holding the telephone, or holding a book or magazine. Patients will often complain that the whole hand is involved, though some may be able to localize it to any of the radial 3 or 4 digits. Occasionally, variations in innervation may lead to the small finger being symptomatic as well. Sometimes that sensation can become very uncomfortable and is often described as a burning pain or an intense pins and needles feeling that will frequently awaken the patient from their sleep. The diagnosis is most frequently made on the basis of a history of these symptoms in conjunction with the physical exam (responses to various provocative maneuvers, thenar muscle atrophy, sensibility loss). Occasionally electrodiagnostic testing can be helpful for confirmation.
The treatment depends on the severity and time-course of the symptoms. In some instances CTS can resolve on its own. Night splints often help those who are awoken from their sleep. Steroid injections into the carpal canal can often provide relief of symptoms, though the relief is usually transient. Although it is impossible to determine precisely when permanent nerve damage is imminent, paresthesias that are present throughout much of the day are generally considered to be a warning sign. Surgery to open the carpal tunnel is the most reliable way to relieve the symptoms provided that it's not "too Patients will usually get instant relief from the night pain. Resolution of the parasthesias may take longer. Patients are generally able to use their hands for light activities immediately after surgery, though it may take several weeks before they feel comfortable using them with full force.