How to optimize the evaluation of carpal tunnel syndrome in patients with polyneuropathy?

Abstract

Carpal tunnel syndrome (CTS) is the most frequent consequences of the neuropathy and the CTS on nerve peripheral nerve entrapment. Treatment decision conduction. Development or expertise of new tools is depends on a combination of clinical criteria including always interesting. In this issue, Tokcaer et al propose to tolerance of pain and presence of sensory or motor deficits study the palmar cutaneous nerve, a branch of the median and intensity of electrophysiological abnormalities. nerve which does not pass through the carpal tunnel. Existence of an underlying polyneuropathy in a patient The ratio of conduction velocities of this nerve and the with CTS may complicate the matters since standard first digit median nerve branch appears to be both sensitive electrophysiological explorations are often unable to and specific to detect a CTS in patients with an associated differentiate abnormalities due to the polyneuropathy and polyneuropathy and can thus be used in addition to the entrapment. However, in this situation, conventional methods especially. electrophysiological conclusions are especially important because carpal tunnel syndrome is more frequent in case Jean-Philippe Camdessanche of polyneuropathy, particularly in association with Department of Neurology, Bellevue Hospital, CHU Saint-Etienne, Furthermore, an early diagnosis of carpal 42055 Saint-Etienne Cedex 02 France. E-mail: jean.philippe.camdessanche@chu-st-etienne.fr tunnel entrapment may be warranted since the polyneuropathy frequently reduces nerve abilities to regenerate preventing a good outcome after treatment. On References another hand, interpreting electrophysiological abnormalities in patients with polyneuropathy may lead 1. Tokcaer AB, Goðuþ F, Gullap S, Keleþ I, Gokce M. The role of to an over-diagnosis of CTS. sensory nerve conduction study of the palmar cutaneous nerve in In the exploration of CTS, sensory conduction velocities the diagnosis of carpal tunnel syndrome in patients with polyneu­ ropathy. Neurol India 2007;55:17.21. are clearly more sensitive than motor conduction velocities 2. Perkins BA, Olaleye D, Bril V. Carpal tunnel syndrome in patients to detect abnormalities. [3] However, in case of with diabetic polyneuropathy. Diabetes Care 2002;25:565-9. polyneuropathy, sensory nerves are often more severely 3. American Association of Electrodiagnostic Medicine, American Academy of Neurology and American Academy of Physical Medicine involved. Comparison of median and ulnar sensory nerve and Rehabilitation. Practice parameter for electrodiagnostic studies velocities on the fourth digit or on two different digits is in carpal tunnel syndrome: Summary statement. Muscle Nerve the usual method to differentiate the respective 2002;25:918-22. diabetes.