Prediction of trapezius muscle activity and shoulder, head, neck, and torso postures during computer use: results of a field study

Table 3 Parameters in each category used in the expanded model predictions of median trapezius muscle activity and shoulder, head, neck, and torso posture

Median	Individual factors (Total = 16)	Job characteristics (Total = 12)	Computer work behaviors (Total = 20)	Psychosocial factors (Total = 17)	Workstation setup (Total = 27)	Health and pain (Total = 6)	Leisure time activities (Total = 6)	Key (p-values)	Mouse (p-values)	Idle (p-values)	Total number of predictors
Shoulder EMG (%MVC)
Right Trapezius¹	16		30,37,41,46	56,64	71,87	93		<0.01			10
Left Trapezius	2,10	18,26	29,37	60,64	76,78	93	102				12
Shoulder Posture (degrees)
Right Abduction	2		40	52,61,65	76,77,82,85	93					10
Left Abduction	4,11		33,38,43		72,82		102				8
Right Flexion				51,60,65			102				4
Left Flexion	2		45	67,81,85		93					6
Right Internal Rotation	16	20,22	33,45,46,47	53,58,55,63				0.05	< 0.01		11
Left Internal Rotation			30,45,46,48	52,64,65	84,92			<0.01		0.05	9
Head Posture (degrees)
Tilt		22	43	59,61	78	98					6
Flexion		24	47	52	77,78,83,88,89	96			0.01		9
Neck Posture (degrees)
Tilt		17	42,43	70,72,78,85							7
Flexion		17,21	29	55,59	67,72,81,89,90						10
Torso Posture (degrees)
Tilt		24	29,35	64	66,78	98					7
Flexion			45	55,59	74,78,89						6

Numbers in each category correspond to the numbers assigned to each parameter described in Appendix A.

ISSN: 1471-2474