Registered nurses have a higher incidence rate of work-related musculoskeletal disorders (MSDs) compared with the overall rate for MSDs in the U.S. Attention has been on back pain in nurses, but the lower extremities are also a frequent site of discomfort in nurses, though only a few studies have reported on this problem, investigations of risk factors are limited, and reports of successful interventions are primarily anecdotal. The goal of this dissertation study was to investigate factors that might be associated with nurses’ lower extremity musculoskeletal disorders, through a comprehensive examination of work-related and individual factors.
A comprehensive, theoretical, etiological model of development of lower extremity work-related musculoskeletal disorders in hospital in-patient staff nurses (the “Nurse Lower Extremity MSD Risk Factor Model”) was developed through a review of the literature to provide a framework for the research. A mixed methods research study was conducted to investigate the prevalence of hospital in-patient staff nurses’ lower extremity discomfort and examine the associations between musculoskeletal complaints and potential risk factors in the Nurse Lower Extremity MSD Risk Factor Model. Quantitative and qualitative data were collected through a cross-sectional epidemiological survey study, an objective activity monitoring study, as well as semi-structured interviews.
A total of 502 staff nurses from 19 in-patient nursing units of several hospitals located in the Midwestern region of the U.S. completed the survey study, providing a response rate of 65%. Seventy-three percent of the respondents reported musculoskeletal discomfort in at least one part of the lower extremity (hip/thigh, knee, and/or foot/ankle) in the last 12 months (12 mo prevalence). Sixty-four percent experienced discomfort in at least one part of the lower extremity in the last 7 days (7-day prevalence). The mean typical intensity of discomfort in the three regions was 4.8 -5.0 on a 1-10 point scale. Corresponding statistics for the low back were as follows: 77.5% 12 mo prevalence, 54.2% 7-day prevalence, and 5.2 mean intensity of discomfort. Nurses were asked to estimate the percentage of their shift that they were on their feet or sitting. Their mean estimates for walking, standing, and sitting were 41%, 37%, and 21%, respectively.
To provide an objective estimate of lower extremity activity (sitting, standing, and walking exposures), 19 nurses who also participated in the questionnaire phase of the study wore an accelerometer and a pedometer; most of them wore the devices for 3 shifts. On average, the nurses were found to walk 8256 steps over a 12-hour shift; the mean measured times for walking, standing, and sitting were 1.7, 6.6, and 3.7 hours, respectively, which correspond to 14%, 55%, and 31% of a 12-hour shift. When compared with the estimates provided on the questionnaire, the nurses substantially overestimated the percentage of time they walk during a shift, while underestimating the percentage of time they stand and sit.
Logistic regression models were developed for each part of the body, to examine the associations between self-reported musculoskeletal discomfort and corresponding workplace and personal factors in the conceptual model. The coefficients and odds ratios for each variable in these models are reported and interpreted. Then, based on the logistic regression models, the estimated probability a selected group reporting discomfort for different body parts is presented and discussed. The lower extremity (any parts) 12-month discomfort was associated with personal characteristics including gender and BMI, physical work exposure such as frequency of bending, frequency of patient handling tasks, patient handling method, psychosocial factors including job satisfaction, as well as individual health factors including foot conditions. Based on the logistic regression models, the probability estimation for discomfort at different body parts for one particular nurse (an example case) is presented to demonstrate how such models can be used.
Semi-structured interviews were conducted with 31 nurses who responded to the questionnaire to validate some of the survey questions, gain insights into topics that were not covered comprehensively on the survey, and explore additional factors that might be related to lower extremity musculoskeletal discomfort. The interview results confirmed some of the responses that were collected from the survey study. The interview results also confirmed that lower extremity discomfort in nurses is a complex, multiple factors problem. These factors include physical work exposure, psychosocial work factors, organizational factors, workspace design, and individual factors. This verified the conceptual model, and also supplied additional information that was not captured in the statistical modeling.
In summary, this research has shown that lower extremity discomfort is prevalent in hospital in-patient staff nurses. It also demonstrated that nurses are exposed to a host of factors that are associated with lower extremity discomfort. It further demonstrated the value of a mixed methods approach to investigating this multiple-factors, multi-dimensional issue. This dissertation study improved our knowledge about the prevalence and factors associated with the prevalence of nurses’ lower extremity work-related musculoskeletal disorders. Our long-term goal is to reduce the incidence rate of lower extremity musculoskeletal discomfort in nurses, and eventually benefit the overall well-being of nurses and their patients. As such, next steps in this line of research should include discussions with nurses and other key stakeholders about developing and evaluating interventions to reduce the prevalence of lower extremity discomfort in nurses, many of whom are working in pain or must change jobs due to their pain. Given the critical shortage of nurses, effective interventions could be valuable to nurses, hospitals, and the public in general.