The impact of cell phone texting on superficial blood flow, touch threshold, and symptoms for individuals with carpal tunnel syndrome

BACKGROUND: It is unclear how individuals with carpal tunnel syndrome (CTS) are affected by texting, or how the texting performance of those with CTS might be impaired or different from individuals without CTS. OBJECTIVE: The primary purpose of this case-control study was to determine the immediate effects of texting on superficial blood flow, sensory threshold, and symptoms of fatigue, numbness, and pain for individuals with CTS compared to asymptomatic age-matched controls. Another objective was to detect differences in texting performance between the two groups. METHODS: Superficial blood flow, pain, fatigue, numbness, and touch threshold were measured before, and at three time points following a standardized 15-minute texting task. Overall texting speed was compared between groups. RESULTS: Changes in red blood cell concentration after the texting task was not significantly different for either the CTS group or controls for any of the measurement time points. Mean touch thresholds at baseline were 4.0 g/mm2 for the CTS group versus 2.6 g/mm2 for healthy controls; a 53%greater touch threshold. Following the texting task, touch threshold did not change for normal controls, but increased to 6.7 g/mm2 for the CTS group, representing a significant increase in touch threshold from baseline. Texting performance was compromised in people with CTS, and symptoms worsened with a short-term controlled texting task. CONCLUSIONS: Our results suggest that texting performance is limited in individuals with CTS and that texting results in a short term increase in touch threshold values for individuals with CTS. Further study is needed to determine the effect of long term texting on carpal tunnel pressures.