Limited evidence was also found for a causal relationship between  computer work per se and computer mouse time related to tension neck syndrome , but the evidence for keyboard time was insufficient .
Insufficient evidence was found for an association between other musculoskeletal diagnoses of the neck and upper extremities , including shoulder tendonitis and epicondylitis , and any aspect of computer work .
Conclusions There is limited epidemiological evidence for an association between aspects of computer work and some of the clinical diagnoses studied .
Background This review examines the evidence for an association between  computer work and neck and upper extremity disorders ( except carpal tunnel syndrome ) .
Computer mouse position as a determinant of posture, muscular load and perceived exertion.
OBJECTIVES This study concerned the influence of 6 positions of the computer mouse on the work table on posture , muscular load , and perceived exertion during text editing . METHODS An optoelectronic 3-dimensional motion analysis system was used to register the postures of 10 men and 10 women using  video display units . Muscular load was also registered ( with electromyography ) , as was perceived exertion ( with rating scales ) . RESULTS A neutral posture with a relaxed and supported arm showed the least perceived exertion , and the electromyographic results showed low activity in both trapezius muscles in this position . Short operators ( all women ) showed a numerically higher activity in the 4 examined muscles than the tall operators ( all men , except 1 ) . This finding could be related to lower muscle force among women and to anthropometric differences , which also influence biomechanic load moments . Narrow-shouldered operators ( 8 women and 1 man ) and short operators worked with larger outward rotation and abduction of the shoulder in a position of the mouse lateral to the keyboard than the broad-shouldered ( 7 men and 2 women ) and tall operators did . Arm support markedly reduced muscle load in the neck-shoulder region among the operators . CONCLUSIONS The operators using video display units in this study preferred to use the mouse on a table in a close to relaxed , neutral posture of the arm in combination with arm support . Short and narrow-shouldered operators worked in more strenuous postures of the arm when the mouse was located lateral to the keyboard
Limited evidence was also found for a causal relationship between  computer work per se and computer mouse time related to tension neck syndrome , but the evidence for keyboard time was insufficient .
Insufficient evidence was found for an association between other musculoskeletal diagnoses of the neck and upper extremities , including shoulder tendonitis and epicondylitis , and any aspect of computer work .
Conclusions There is limited epidemiological evidence for an association between aspects of computer work and some of the clinical diagnoses studied .
Background This review examines the evidence for an association between  computer work and neck and upper extremity disorders ( except carpal tunnel syndrome ) .