Clinical, Physical, and Neurophysiological Impairments Associated With Decreased Function in Women With Carpal Tunnel Syndrome

Abstract

Cross-sectional study. To examine the associations between clinical (pain), physical (cervical range of motion [ROM] and pinch grip force), and neurophysiological (pressure pain thresholds) outcomes and self-reported function and disability in women with carpal tunnel syndrome (CTS). The association of physical and physiological variables with self-rated function and disability in patients with CTS has not been fully determined. A better understanding of the association between potentially modifiable risk factors, such as limited cervical ROM, could assist clinicians in optimizing therapeutic programs for this group of patients. One hundred fifty-four women with CTS were recruited. Demographic information and data on duration of symptoms, pain intensity, depression, cervical ROM, pinch grip force, and pressure pain thresholds over the neck, hand, and leg were collected. Self-reported function and disability were measured with the functional status subscale of the Boston Carpal Tunnel Questionnaire. Correlation and regression analyses were performed to determine associations between variables. There were significant positive correlations between the functional status subscale score and pain intensity (r = 0.36, P<.001), depression (r = 0.32, P<.001), and duration of symptoms (r = 0.23, P = .005). Significant negative correlations were also observed between the functional status subscale score and pinch grip force of the index finger (r = -0.25, P = .002) and little finger (r = -0.28, P<.001), ROM in cervical flexion (r = -0.22, P = .003) and lateral flexion away from the side of CTS (r = -0.24, P = .002) and toward the side of CTS (r = -0.16, P = .045), and pressure pain threshold over C5-6 (r = -0.34, P<.001), the carpal tunnel (r = -0.35, P<.001), and the tibialis anterior muscle (r = -0.26, P<.001). Stepwise regression analyses revealed that pain intensity, thumb and little finger pinch grip force, severity of depression, and cervical ROM in lateral flexion away from the side of CTS explained 38.2% of the variance in functional status (R2 = 0.411, adjusted R2 = 0.382, F = 15.42, P<.001). CONCLUSION This study found that a number of modifiable factors are associated with self-reported function in women with CTS. Future longitudinal studies will help to determine the clinical implications of these findings.