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 ) .
A prospective study of computer users: II. Postural risk factors for musculoskeletal symptoms and disorders.
BACKGROUND Despite widespread recommendations regarding posture during computer use , associations between specific postures and musculoskeletal health are not well characterized . METHODS Six hundred and thirty-two newly hired computer users were followed prospect ively to evaluate associations between posture and neck or shoulder ( N/S ) and h and or arm ( H/A ) musculoskeletal symptoms and musculoskeletal disorders . Participants ' postures were measured at entry and they reported symptoms on weekly diaries . Participants reporting symptoms were examined for specific disorders . Multivariate Cox regression models were used to estimate associations between postural variables and risk of symptoms and disorders , controlling for confounding variables . RESULTS Keying with an inner elbow angle > 121 degrees , greater downward head tilt , and presence of armrests on the participants chair were associated with lower risk of N/S symptoms or N/S disorders .  Keying with elbow height below the height of the " J " key and the presence of a telephone shoulder rest were associated with a greater risk of N/S symptoms or N/S disorders . Horizontal location of the " J " key > 12 cm from the edge of the desk was associated with a lower risk of H/A symptoms and H/A disorders . Use of a keyboard with the " J " key > 3.5 cm above the table surface , key activation force > 48 g , and radial wrist deviation of > 5 degrees while using a mouse was associated with a greater risk of H/A symptoms or H/A disorders . The number of hours keying/week was associated with H/A symptoms and disorders . CONCLUSIONS The results suggest that the risk of musculoskeletal symptoms and musculoskeletal disorders may be reduced by encouraging specific seated postures
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 ) .