Optimum design of a lumber support belt to reduce the physical workload of the low back

Abstract

Low back pain is a major medical problem frequently encountered in the field of occupational health, and lumber support belts are often used for the prevention and treatment of low back pain. This study investigated the effect of width (60, 90, 120, and 150 mm) and thickness (1, 2, 3, and 4 layers) of lumber support belts on the physical workload of the low back in order to optimize these lumber support belt parameters and thus minimize workload. Subjects performed a bandage-wrapping task with and without the use of a lumber support belt. The trunk segment was divided into 3 areas: the chest, abdomen, and pelvis. The chest, abdominal, and pelvic angles were measured, and the L5/S1 compression force was estimated. In addition, subjective scores of perceived abdominal discomfort and perceived difficulty of the bandage-wrapping task were measured. We found that the use of a lumber support belt during this task decreased the abdominal angle and increased the chest and pelvic angles while reducing the L5/S1 compression force. A wider lumber support belt increases compression forces, perceived discomfort, and perceived difficulty of the task, whereas a thicker lumber support belt increases perceived discomfort. Optimization results showed that a 60-mm-wide, 3-layer lumber support belt is the most effective in reducing the workload of the low back during a task involving trunk flexion.

Keywords

• ergonomics
• occupational biomechanics
• lumber support belt
• low back pain
• working posture
• optimization
• response surface method