Spade design,lumbar motions,risk of low-back injury and digging posture

A laboratory investigation of the ergonomics of digging is reported. Data on lumbar motions, ground reaction forces and posture were obtained simultaneously as subjects transferred sand from one container to another while standing on a force platform. Digging with a conventional spade was found to carry a substantial probability of inclusion in a high-risk group for low back injury. A prototype two-handled spade reduced the probability by approximately 8%. used but this was partly offset by an increase in twisting. From a fundamental point of view, the prototype merits further evaluation. Digging is a hazardous task when conventional spades are used and that ergonomic redesign can reduce the risk of back injury.