Safety analysis of patient transfers and handling tasks.

BACKGROUND Low-back disorders are related to biomechanical demands, and nurses are among the professionals with the highest rates. Quantification of risk factors is important for safety assessment and reduction of low-back disorders. OBJECTIVE This study aimed to quantify physical demands of frequent nursing tasks and provide evidence-based recommendations to increase low-back safety. METHODS Thirty-six volunteer female nurses participated in a cross-sectional study of nine nursing tasks. Lumbar range of motion (ROM) and motion during nursing tasks were measured. Compression and shear forces at L5/S1, ligament strain and percentage of population without sufficient torso strength to perform 14 phases of nine nursing tasks were estimated. RESULTS Peak flexions during trolley-to-bed, bed-to-chair and chair-to-bed transfers reached the maximum flexion ROM of the nurses. Average lumbar flexion during trolley-to-bed transfers was >50% of flexion ROM, being higher than during all other tasks. Mean (SD) compression at L5/S1 (4754 N (437 N)) and population without sufficient torso strength (37% (9%)) were highest during the pushing phase of bed-to-trolley transfers. Shear force (487 N (40 N)) and ligament strain (14% (5%)) were highest during the pulling phase of trolley-to-bed transfers. CONCLUSIONS Nursing tasks impose high biomechanical demands on the lumbar spine. Excessive lumbar flexion and forces are critical aspects of manual transfers requiring most of the nurses' capabilities. Evidence-based recommendations to improve low-back safety in common nursing tasks were provided. Fitness to work, job modifications and training programs can now be designed and assessed based on the results.