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Biomechanics during ladder and stair climbing and walking on ramps and other irregular surfaces.

Merryweather-AS; Bloswick-DS
Biomechanics and ergonomics, 2nd edition. Kumar, S ed., Boca Raton, FL: CRC Press, 2007 Dec; :657-678
Accidents and injuries resulting from climbing on ladders and stairs and walking on ramps and irregular surfaces occur in both the occupational and nonoccupational environments. General guidelines for the design and use of these systems have been developed to reduce the chance of accident or injury, but considerable biomechanical slresses still exist. In this chapter hand and foot forces, upper and lower extremity moments, low-back stresses, physiological cost during ladder and stair use, and lower-extremity biomechanical stresses when walking on uneven surfaces are reviewed and summarized. During ladder use, upper extremity moment and hand forces are highest during the use of vertical ladders. Lower extremity moment and foot force are highest when using ladders slanted at 20 degrees. Foot slip potential, however, appears to be highest for vertical ladders. Peak back stresses also appear to be relatively high when climbing vertical ladders at a fast speed. Energy expended during ladder climbing is very high. Both stair ascent and descent require joint moments considerably higher than those required for level walking and significant ranges of motion. Foot forces and body instability, however, appear to be higher during stair descent than ascent. Back stresses during stair use are not considerably greater than those during level walking. Energy expenditure requirements during stair ascent, although lower than ladder climbing, exceed that of any other routine daily physical activity. Ambulation over ramps and other irregular surface terrain changes normal gait parameters such as cadence, stride length, differences in stance and swing phases, and some biomechanics of walking. The data available describing the differences in moments and lower extremity joint forces are limited for walking over irregular surfaces; however, data from studies on uphill and downhill walking and running indicate deviations in ground reaction forces and resulting lower extremity joint moments. The position of the center of mass and behavior of upper extremities appears to be altered, but is not well understood. Further research is needed to describe the kinematics and biomechanics of walking over laterally sloped and other irregular surface terrains.
Biomechanics; Walking-surfaces; Step-ladders; Equipment-design; Biochemical-analysis; Body-distribution; Body-mechanics; Floors; Force; Muscle-function; Muscle-physiology; Accident-prevention; Accidents; Injuries; Injury-prevention; Extension-ladders; Extremities; Back-injuries; Motion-studies; Physiological-stress; Hand-injuries; Foot-injuries; Energy-metabolism; Slope-stability; Kinetics; Kinetic-energy; Body-distribution
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Biomechanics and ergonomics, 2nd edition
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University of Utah, Salt Lake City, Utah
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division