Role of Anthropometric Characteristics in Idiopathic Carpal Tunnel Syndrome

Abstract

ObjectiveTo investigate the possible association of external and ultrasonographic measurements of the hand and wrist with median nerve conduction studies. DesignTwo group comparison study. SettingOutpatient neurophysiology laboratory and radiology department in a university hospital. ParticipantsPatient group (n=50; 40 women) with clinically overt and electrophysiologically proven idiopathic carpal tunnel syndrome and a control group of age- and sex-matched healthy volunteers (n=50). InterventionsNot applicable. Main Outcome MeasuresThe following measurements were taken: (1) motor and sensory conduction studies of the median nerve; (2) external hand and wrist dimensions (hand ratio and wrist ratio); and (3) ultrasonographic dimensions of the carpal tunnel (carpal tunnel inlet ratio and carpal tunnel outlet ratio) and inlet cross-sectional area and outlet cross-sectional area of the median nerve at the tunnel. ResultsDifferences between patients and controls were significant for hand and wrist ratios and all ultrasonographic dimensions. Sensory conduction velocity and distal motor latency of the median nerve in all 100 subjects were well correlated with hand ratio, wrist ratio, carpal tunnel inlet ratio, and carpal tunnel outlet ratio estimates. Wrist ratio was significantly correlated with carpal tunnel inlet ratio and carpal tunnel outlet ratio. ConclusionsA particular hand and wrist configuration, that is, short and wide hand with square wrist matching to narrow and deep tunnel entrance demonstrated increased liability for idiopathic carpal tunnel syndrome. For screening purposes, it was suggested that simple external hand or wrist measurements could be used to predict the tendency for carpal tunnel syndrome.