Work technique in lifting and patient transfer tasks

Abstract: The overall aim of this thesis was to explore and develop methods for describing, analysing and assessing work technique in lifting and patient transfer tasks, and to study how the work technique is related to personal factors and aspects of patient quality and safety. The focus was on work technique features with implications for musculoskeletal load and for the development of musculoskeletal disorders. Work technique was viewed in two basic elements: method and individual performance. The thesis is based on biomechanical model studies in the laboratory and observational studies in the field. Results from lifting experiments implied that separate variables should be used for descriptions of work methods and task performances. The work technique varied between the subjects to a greater extent than the individual variability over repetitions of a lift task. Differences between men and women in lifting kinematics were found, e.g. in trunk motion, knee angle ranges and hip-knee inter-joint coordination. An observation instrument for description and a quantitative assessment of work technique in videotaped patient transfer tasks was developed, and an overall score with regard to musculoskeletal hazard and safety was calculated. The validity and reliability of the instrument were mostly satisfactory, both when evaluating the agreements between the observations of each item and when evaluating the agreements between the overall scores.Observations of nurses at orthopaedic wards revealed that a variety of strategies were used to perform two patient transfer tasks. Being older, suffering from low back symptoms and being male were associated with a poor work technique. Patients perceptions of safety and comfort when being transferred were related to the work technique of nurses, both regarding the work technique score, and the nurses own subjective assessments of their work technique.In conclusion, inter-individual variations regarding work technique in lifting and patient transfers tasks suggest that evaluations of work technique may need to be carried out on an individual level. Evaluations should also consider possible differences in work technique between women and men, younger and older persons, and persons with and without low back symptoms. Finally, the transfer skill of nurses could also be regarded as a matter of quality of care.