the effects of caregiver experience on low back loads during floor and overhead lift maneuvering activities

this study investigated the effects of caregiver experience on peak external forces and moments generated at the l5/s1 joint of the low back when maneuvering loaded floor-based and overhead-mounted patient lifting devices. twenty caregivers were divided into more-experienced and less-experienced groups based on the product of two factors: their years of lifting experience and the frequency of lifting the caregivers had done in the past. ground reaction forces and moments as well as motion capture data were recorded while caregivers performed five different maneuvering tasks with both lifts in each of three conditions (caregiver subjects worked alone, as the primary caregiver in a pair, and as the secondary caregiver in a pair). six outcome measures (net external forces and moments at the l5/s1 joint) were recorded. multivariate analyses of variance of all net external forces and moments were done separately for the floor and overhead lifts. a significant effect of experience level was found for the floor lift (p = 0.006) but not for the overhead lift (p = 0.163). a follow-up univariate analysis of floor lift activities found significant differences between more-experienced and less-experienced caregivers for turn, push and legs up activities.