Date of this Version
Low-back pain and injury are responsible for a major portion of lost workdays and injury compensation claims. The use of back support belts has been forwarded as a counter measure towards reducing low-back injuries in the industrial setting.
PURPOSE: The purpose of this study was to determine if a back support belt relieves stresses encountered by the lumbar spine during stoop type lifting and potentially reduce the risk of injury.
METHODS: Twelve male participants (49.7±3.7 years) performed two sessions of stooped type lifting with a loaded milk crate (11.5 kg), at 4 repetitions per minute, for 15 minutes in accordance with the NIOSH lifting equation. One lifting session was performed without a support belt, while the other with a support belt. Three sets of fluoroscopic images were collected with the participants positioned at the initiation (flexed trunk), mid-range, and completion of the lift (erect standing). The first series of images were collected under a no-load condition, while the second (no support belt) and third series (support belt) of images were collected with the participants lifting the 11.5 kg milk crate. Images were imported into AutoCAD where lumbar disc deformation and joint angles were measured by calculating changes in position of adjacent vertebra (L3-4 and L4-5). A reduction of disc deformation was deemed indicative of reduced stress.
RESULTS: Analysis of variance revealed that compressive and shear disc deformation were reduced while in the erect trunk posture for the support belt condition (p< 0.05). No significant reduction in disc deformation was detected while in flexed trunk postures for the support belt condition (p> 0.05).
CONCLUSIONS: During stoop type lifting, support belts provide a measurable amount of stress reduction of the lumbar spine when the trunk is in the erect posture, with little effect during flexed trunk positions.
This document has been peer reviewed.