Mayer T, Gatchel R J, Keeley J, Mayer H, Richling D
Department of Orthopedic Surgery, University of Texas Southwestern Medical Center, Dallas.
Spine (Phila Pa 1976). 1994 Apr 1;19(7):755-761. doi: 10.1097/00007632-199404000-00005.
A group of 160 incumbent male railroad workers volunteered for a study of lumbar spine physical capacity.
They were initially subjected to inclinometric measurements of sagittal and coronal regional mobility (T12-S1). They also were tested on isokinetic trunk strength measurement devices for sagittal (bending) and axial (twisting) trunk strength at multiple speeds.
Results showed that they demonstrated mild deficits of lumbar sagittal extension mobility, trunk extensor strength, and sagittal/axial high speed (150-180 degrees/sec) trunk strength when compared with population averages from a previously derived normative database of a nonhomogeneous male population (matched for age and body weight).
It was hypothesized that instructions about "correct lifting techniques," uniformly provided to these workers, may have resulted in an unintended decrement in trunk mobility and strength.