Conclusions : Neck pain was not significantly associated with high job dem and s , low skill discretion , low decision authority , or low peer support .
However , when these variables were combined with increased duration of computing tasks , or ergonomic dem and s , they reached significance .
Supervisor support was found to be the only significant buffer capable of preventing these variables reaching significance in female office workers
Introduction : The purpose of this systematic review was to examine literature on workplace factors associated with  neck pain or symptoms in computer users performing clerical functions .
Torque-EMG-velocity relationship in female workers with chronic neck muscle pain.
The present study investigated the effect of chronic neck muscle pain ( defined as trapezius myalgia ) on neck/shoulder muscle function during concentric , eccentric and static contraction . Forty-two female office workers with trapezius myalgia ( MYA ) and 20 healthy matched controls ( CON ) participated . Isokinetic ( -60 , 60 and 180 degrees s(-1 ) ) and static maximal voluntary shoulder abductions were performed in a Biodex dynamometer , and electromyography ( EMG ) obtained in the trapezius and deltoideus muscles . Muscle thickness in the trapezius was measured with ultrasound .  Pain and perceived exertion were registered before and after the dynamometer test . The main findings were that shoulder abduction torque ( at -60 and 60 degrees s(-1 ) ) and trapezius EMG amplitude ( at -60 , 0 and 60 degrees s(-1 ) ) were significantly lower in MYA compared with CON ( p<0.001 - 0.05 ) . Deltoideus EMG and trapezius muscle thickness were not significantly different between the groups . While perceived exertion increased in both groups in response to the test ( p<0.0001 ) , pain increased in MYA only ( p<0.0001 ) . In conclusion , having trapezius myalgia was associated with decreased strength capacity and lowered activity of the painful trapezius muscle . The most consistent differences-in terms of both torque and EMG-were found during slow concentric and eccentric contractions . Activity of the synergistic pain free deltoideus muscle was not significantly lower , indicating specific inhibitory feedback of the painful trapezius muscle only . Parallel increase in pain and perceived exertion among MYA were observed in response to the maximal contractions , emphasizing that heavy physical exertion provokes pain increase only in conditions of myalgia
Conclusions : Neck pain was not significantly associated with high job dem and s , low skill discretion , low decision authority , or low peer support .
However , when these variables were combined with increased duration of computing tasks , or ergonomic dem and s , they reached significance .
Supervisor support was found to be the only significant buffer capable of preventing these variables reaching significance in female office workers
Introduction : The purpose of this systematic review was to examine literature on workplace factors associated with  neck pain or symptoms in computer users performing clerical functions .