Thermal behavior of the skin on the wrist and finger extensor muscles during a typing task

Occupational diseases are the second leading cause of sick leave in Brazil, among which musculoskeletal disorders are very common especially among workers whose job includes typing tasks. Thermography analyzes the temperature distribution on the skin surface and is used for diagnosis and prevention of musculoskeletal disorders.

To investigate the thermal behavior of the skin on the wrist and finger extensor muscle area before, during and after a typing task.

Twenty-four workers whose job involves typing were allocated to two groups-with or without elbow, forearm or injury-and performed a 10-minute typing task. Four thermography images were captured from the forearms and fingers at baseline, 0-2, 3-5 and 8-10 minutes and the minimum, maximum and mean temperature was calculated. The data were subjected to factorial ANOVA with software SPSS v 20.0. The significance level was set to 5%.

Minimum (mean difference-d=1.7), maximum (d=0.8) and mean (d=0.39) temperature was lowest on the elbow of participants with forearm injury; maximum temperature was lower on the right compared to the left side (d=0.39). Temperature did not vary as a function of time.

There was difference in skin temperature between individuals with or without forearm injury and between the right and left sides, but not as a function of time. In future studies tasks should be longer and/or have set typing speed and goals.