Prevalence of Carpal Tunnel syndrome in wheel-chair users due to medullary lesion

Abstract

Medullary lesions create numerous functional limitations directly related to the loss of nervous functions. However, the mechanics associated with the use of a wheelchair impose a load on the upper limbs that seems to be linked to secondary lesions in the tendinous and nervous structures. Objective: This study seeks to evaluate the appearance of signs of electromyographic impairments of the median nerve around the carpal tunnel in individuals who use wheelchairs due to medullary lesion. Method: Following a transversal design, all the individuals with medullary lesion in the rehabilitation program at the HC-FMUSP Institute of Physical Medicine and Rehabilitation in the year 2010 were submitted to a study of nervous conduction and electromyography. Those findings were correlated with biodemographic and clinical variables, as well as to characteristics of the use of wheelchairs. Results: Twenty-eight (28) individuals were evaluated, with an average age of 41.4 years (60.7% males). Most patients moved the wheelchair for less than four hours and would move it less than 500 meters a day. An absence of painful symptoms was found in 67.9%, while only 7.1% presenting positive Phalen and/or Tinel test. Half of the sample presented the neurophysiological diagnostic of carpal tunnel syndrome (CTS), which had a statistically significant association with age (p = 0.024), but not with the time and distance moving the wheelchair daily, the use of protection or adaptation of the wheelchair, of pain in upper limbs, or the presence of positive signs of CTS in the physical exam. Conclusion: We concluded that the electromyographic signs of CTS are very prevalent in these individuals, which suggests more situations of risk for the integrity of their upper limbs and demands the development of a more efficient biomechanical strategy for prevention.