Cumulative Spine Loading - Fundamentals and Assessment Tools for Occupational Ergonomics - page 311

TABLE 13.1 Cumulative Loading Magnitudes Reported in the Research Literature. Values
Given Represent Averages + 1 Standard Deviation Unless Noted Otherwise.

Cases Controls

Compression (MN s)
Jager et al. (2000) n / a 10.8 to 36.0 (range) (n ¼ 8)

Kumar (1990) F 15.6+5.0 (n ¼ 6) F 6.6 +5.5 (n ¼ 8)

C 13.5 +12.1 (n ¼ 52) C 9.3 +7.7 (n ¼ 95)

Norman et al. (1998) 21.0 +4.72 (n ¼ 104) 19.5 +3.84 (n ¼ 130)

Shear (MN s)
Jager et al. (2000) n / a n / a

Kumar (1990) F 2.5+0.9 F 1.0+1.0

C 2.2+ 4.2 C 1.6+1.5

Norman et al. (1998) 1.52 +0.64 1.32 +0.45

Moment (MN m s)
Jager et al. (2000) n / a n / a

Kumar (1990) n / a n / a

Norman et al. (1998) 0.55 + 0.24 0.47 + 0.15

Note: n / a is not available.

hand forces and uses postures of the elbow (3), shoulder (10), neck (8) and trunk (18) as inputs to a 3D-
biomechanical model. The video recordings with rates of 2 to 3 frames sec are opened directly into the

software and evaluated. The justification for this sample rate will be presented later in this chapter.
Alternative approaches have been used to yield cumulative loading. Electromyography (EMG) to com-
pression relationships (Mientjes et al., 1999; Potvin et al., 1990) have been examined as one approach to
provide estimates of cumulative loading. Electromagnetic tracking devices have also been used to provide
valid real-time cumulative compression in 2D (Agnew et al., 2002, 2003). The relationship between heart

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FIGURE 13.10 3DMatch user interface for using postural matching and external forces to calculate 3D spine loads
using a biomechanical model.