From precision demands to neck and upper extremity pain

nd d s t o ec k a n u u Despite a whole body of literature, the aetiology of neck and upper extremity pain, also referred to as RSI, Repetitive Strain Injury, is poorly understood. Working with high precision has been suggested as a risk factor for neck and upper extremity pain. In this thesis a Precision-Pain Model is proposed which hypothesises how precision demands could lead to neck and upper extremity pain. In line with the Precision-Pain Model, it is concluded that: 1) higher precision demands lead to higher impedance (i.e. resistance against imposed motion as indicated by a higher muscle activity and a higher pen pressure) in combination with changes in kinematics, 2) proprioception and task performance in terms of positional precision are impaired in fatigued subjects and in subjects with neck and upper extremity pain, and 3) precision demands could be associated with arm-hand pain. A general increase of impedance in computer tasks with high precision demands was not found for these subject populations as compared to healthy controls. An increase in impedance could have been an indication of the presence of a vicious cycle, as proposed by the Precision-Pain Model, which may lead to pain, but the results of the present thesis show that the evidence for a vicious cycle is still inconsistent. Recommendations to reduce precision demands in the task or to facilitate precision work are given. Uitnodiging