A correlation between clinical severity and functional state with nerve conduction studies findings in patients with carpal tunnel syndrome: a systematic review

Carpal Tunnel Syndrome is the most common compressive neuropathy in the general population, and it may lead to disabling symptoms and significant functional limitation. This systematic review covered Pubmed, Medline, Embase, Cochrane, CINAHL, LILACS, and SCIELO databases, with no time or language delimitations. The PICO strategy defined the search strategy with keywords extracted from the Medical Subjects Headings, and the quality of the studies was evaluated by the Agency for Healthcare Research and Quality (AHRQ) scale. Overall, 857 studies were identified, of which only 10 fulfilled the inclusion criteria. Despite the good results shown, a noticeable heterogeneity was observed among the studies included, associated with methodological discrepancy and to limited sample size in a few of them. Four studies showed no correlation between electrophysiological findings and clinical symptoms and signs, whereas three could demonstrate such association and other three studies had equivocal results. Other studies are necessary, with better methodological standards and more homogeneous and precise evaluations, so as to improve the level of scientific evidence.