Carpal Tunnel Syndrome: Knowing When to Refer for Testing is as Easy as 1, 2, 3
Newswise — Does your physician know when it is appropriate to refer you to a specialist to diagnose carpal tunnel syndrome (CTS)? Due to a high prevalence of CTS, and the number of other conditions that mimic symptoms of CTS, a team of researchers set out to develop an easy screening questionnaire to help physicians determine when it is appropriate to refer a patient for nerve conduction studies and needle electromyography (EMG) - the two electrodiagnostic tests, most commonly used to diagnose CTS.
The carpal tunnel is a small tunnel made of bones and ligaments in the wrist. The median nerve runs down the forearm through the tunnel into the hand on the palm side of the hand and provides feeling to the hand and fingers. The median nerve can become irritated by inflammation in this tunnel, which leads to carpal tunnel syndrome. CTS can be a result of many factors arising from work and lifestyle, health, injuries, and even genetic predisposition. The most common cause of CTS is repetitive hand motion. Common symptoms include tingling, numbness and pain in the hand, which are typically worse at night and can even cause people to awaken from sleep.
A simple seven item screening questionnaire was used to screen patients with possible CTS prior to referral for electrodiagnostic testing. The questionnaire was completed by 100 consecutive patients. Three key questions were found to predict the diagnosis of CTS: 1) tingling in at least two of the first four digits; 2) symptoms worse during the night/on awakening; and 3) improvement on shaking the hand. With at least two affirmative responses to three questions the sensitivity of the questionnaire to predict abnormal electrodiagnostic test was 97% (p < 0.001). According to Dr. Simon Podnar, "It seems that only patients with the most advanced CTS may be missed by the questionnaire; therefore looking for muscle atrophy and abnormal skin sensation in the hand is not to be skipped on physical examination by the doctor."
This simple questionnaire proved to be a useful screening tool with a high sensitivity for predicting electrodiagnostic abnormalities typical for CTS. Used by clinicians in combination with physical examination, the questionnaire can result in more timely referrals for electrodiagnostic testing, diagnosis, and treatment for patients with CTS.
The complete findings and results of this study are being presented at the American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM) 55th Annual Meeting in Providence, Rhode Island, September 17-20, 2008. The AANEM is the largest organization worldwide, with over 5000 members dedicated to advancing neuromuscular, musculoskeletal, and electrodiagnostic medicine.