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Interventions to Reduce Back Pain in Rehabilitation Hospital Nursing Staff
Background and Significance of the Problem
Nursing personnel (registered nurses [RNs], licensed practical nurses [LPNs], and nursing aides [NAs]) have one of the highest job-related injury rates of any occupation (Leighton & Reilly, 1995; U.S. Department of Labor, 2005). The majority of these injuries are musculoskeletal, particularly back strains and sprains (Harber et al., 1985; Knibbe & Friehle, 1996). In the industrial classification that includes hospitals and nursing homes, “Education and health services,” the incidence rate of nonfatal occupational strains and sprains (80 per 10,000 workers) was the third highest, after “Construction” (91.2) and “Trade, transportation and utilities”(81.7) (U.S. Department of Labor, 2005). In the United States, NAs are ranked second after laborers among all occupations for the number of nonfatal musculoskeletal disorders resulting in days away from work (U.S. Department of Labor). In addition to the high incidence of back injuries, the prevalence of back pain among direct patient care staff is higher than many other occupational groups (Menzel, 2004).
Personal consequences of back injuries to nursing personnel include prolonged periods of disability that affect both work and home life and lead to loss of income from unscheduled absences and the potential loss of career and earning capacity (Helminger, 1997). Consequences to employers include the high cost of workers’ compensation insurance to pay for medical care for injured workers and lost time.
Efforts to Reduce the Problem
Efforts over the past two decades to decrease the risk of injuries related to providing patient care by addressing body mechanics alone have been largely unsuccessful (Hartvigsen, Lauritzen, Lings, & Lauritzen, 2005; Lagerstrom & Hagberg, 1997; Owen, 2000). Ergonomic interventions using patient handling equipment, such as powered mechanical lifts and friction reducing devices, however, have been shown to reduce back injuries, compensation costs, and lost time (Engst, Chhokar, Miller, Tate, & Yassi, 2005; Owen, Keene, & Olson, 2002; Ronald et al., 2002). Based on the findings of these and other studies, the American Nurses Association in 2003 published a position statement calling for the elimination of manual patient handling through use of patient handling equipment.
Addressing physical risk factors alone may not be sufficient to reduce low back pain (LBP) in nursing personnel. Yip (2001) found an association among work stress, manual lifting, and LBP prevalence, concluding that “prevention among nurses is likely to lie in improved ergonomics and psychological health in their workplace” (p. 794). Feyer and colleagues (2000) concluded that the incidence of occupational LBP in nurses “may be improved by management of psychological distress” (p.116). These studies demonstrate the importance of addressing psychosocial factors in any back pain intervention program and suggest a need to teach nursing personnel how to manage stress and pain, while at the same time reducing physical (ergonomic) stressors.
Cognitive Behavioral Therapy
Psychosocial stress and pain management interventions in work settings have been shown to reduce anxiety, depression, and health complaints (van der Klink, Blonk, Schene, & van Dijk, 2001). Cognitive-behavioral therapy (CBT; based on the theory that thought influences both emotion and behavior) is a psychoeducational program that has been shown to be effective in reducing chronic pain (Flor & Birbaumer, 1993; Flor, Fydrich, & Turk, 1992), and the American Psychological Association has endorsed CBT as an evidence-based method effective in altering exercise, relaxation, and fear avoidance of activity and work, all of which are critical to adjusting to pain and injury. Several cognitive styles, or thinking patterns, have been identified as particularly maladaptive and related to poor outcome, distress, and likelihood of injury (Geisser, Robinson, & Riley, 1999). CBT is a multimodal treatment aimed at reducing maladaptive thinking patterns by replacing them with more adaptive patterns and altering maladaptive behavior patterns by replacing them with functional alternatives that are critical to adjustment to pain and injury (e.g., exercise, relaxation). Group and individual versions of CBT have been shown to be effective, though group versions have received more study. CBT has been shown to affect emotional, pain behavior, and healthcare use outcomes. Linton and Ryberg (2001) found that this type of therapy had a strong preventive effect on low back pain disability. This supports the findings of Hasenbring, Ulrich, Hartman, and Soyka (1999).
This pilot study was conducted to determine whether rehabilitation hospital nursing personnel would attend CBT sessions (pain and stress management) on their own time and how large an effect CBT and patient handling equipment would have (singly and combined) on measures of back pain, disability, stress, and related variables. The theory for the effect of CBT on back pain and disability is that when CBT is used to improve coping skills, then stress, pain and resulting disability will decrease. The purpose of gathering information on feasibility (attendance at sessions) was to assess whether this research on CBT should continue as an intervention for this occupational group. If CBT was well attended, effect sizes (magnitude of differences between before and after program outcome variables) were to be used to estimate the sample size needed for a larger study.
The authors considered three hypotheses: a) CBT alone improves measures of back pain and its affective components: burnout, disability, fear avoidance, job satisfaction, pain coping skills, and stress; b) ergonomic intervention alone improves measures of back pain and its affective components, such as burnout, disability, fear avoidance, job satisfaction, pain coping skills, and stress; c) CBT combined with ergonomic intervention improves measures of back pain and its affective components: burnout, disability, fear avoidance, job satisfaction, pain coping skills, and stress more than ergonomic intervention alone.
Materials and Methods
Design and Participants
The University of Florida (UF) Health Sciences Center institutional review board approved this study, which was funded by a grant from the National Institute for Nursing Research through the UF College of Nursing’s Biobehavioral Research Center (BRC). This was a two-group repeated measures experimental design conducted between October 2003 and January 2004.
A group of RNs and NAs (N = 31) working at a Jacksonville, FL, 127-bed state-of-the-art, nonprofit hospital were recruited. They were dedicated to treating patients with brain injury, strokes, spinal cord injury, and comprehensive orthopedic problems. Inclusion criteria included a history of back pain (causation not specified) of at least 1-week’s duration in the past year, not currently on modified duty, and working at least 30 hours a week. Because the study facility was located 75 miles from the research center, few participants responded to posters describing the study by making long-distance inquiry calls. In-person recruiting was used instead. At the time of recruitment, participants signed an informed consent form and were randomized to the intervention group (IG) or control group (CG) by telephone by a BRC statistician using a computerized randomization program. Participants were given appointments to complete research instruments at a later time and were paid $18 per hour for study activities.
Intervention 1. The first intervention (offered to the IG only) consisted of psychoeducational sessions for stress and pain management, a type of CBT. The content from an effective 9-week stress and pain management program for chronic pain patients at the UF Spine Center and Psychology Clinic (Swimmer, Robinson, & Geisser, 1992) was adopted. Then the content was condensed into six 1.5 hour group-discussion sessions, which included the following:
The same psychologist conducted all CBT sessions and provided participants with standardized written materials and tapes. Sessions were held at the hospital either immediately before or after the day shift. Once data collection had been completed in late January 2004, CBT was offered to the CG for ethical reasons.
Intervention 2. The second intervention was ergonomic and offered to both groups (as well as all staff on the study units) 1 week after the conclusion of Intervention 1 (Measurement 2). Using the recommendations of the Veterans Health Administration’s (VHA) Patient Care Ergonomics Resource Guide (Ergonomics Technical Advisory Group, 2003), the investigators assessed facility equipment needs, made the selected equipment available, and trained nursing staff in its operation and application.
Three equipment vendors loaned assistive devices for the intervention. The two study units, with primarily stroke, spinal cord, and orthopedic patients, received similar numbers of powered stand-assist devices, full-body sling lifts, full-body support lifts requiring no slings (Figure 1), stretchers that converted to chairs, and friction-reducing devices. The principal investigator (PI) and the lifting-equipment vendors provided 1-hour hands-on training sessions for direct care staff on all three shifts on both study floors. All staff members, regardless of whether they were in the study, were trained in order to facilitate equipment use by participants. Consistent with the hospital’s rehabilitation philosophy of encouraging patient self-sufficiency, equipment use was limited to patients who were the most dependent, typically in the first few days after admission. The PI visited study units twice a week for 2 hours on all three shifts to answer questions about operating the new equipment and to suggest opportunities for its uses.
Dependent Variables and Instruments
The dependent variables were stress, back pain, disability, and pain coping skills. Because pain is associated with negative affect (Gaskin, Greene, Robinson, & Geisser, 1992), investigators assessed mood (e.g., depression) for its possible association with measures of disability. Several standardized instruments were used, such as the State-Trait Anxiety Inventory, Back Depression Inventory, Visual Analog Scale of Pain, and the Unscheduled Absence Log.
Data Collection Procedures
At baseline (Measurement 1), participants were asked to complete self-report questionnaires. Time for completion varied from 1 to 2 hours. The CBT sessions were completed in 6 weeks (Measurement 2); thereupon, participants in both groups were asked to complete the same questionnaires that they completed at baseline. At the conclusion of the 6-week ergonomic intervention (Measurement 3), participants in both groups again completed the set of questionnaires. Participants were asked to mail to investigators logs for work attendance and visits to healthcare providers every 2 weeks for 14 weeks (from the start of CBT to the end of the ergonomic intervention). During the ergonomic intervention, all participants were asked to complete equipment usage logs and mail them to investigators every 2 weeks.
SPSS 12.0 was used for all statistical analyses. To determine the effect of Intervention 1 alone, SPSS’s General Linear Model Repeated Measures (GLM RM) analysis of variance (ANOVA) was used to compare scores on outcome measures for the IG with the CG from Measurement 1 to Measurement 2. To determine the effect of Intervention 2 alone, paired sample t tests were used for the CG, comparing Measurement 2 with Measurement 3. To determine the effectiveness of both CBT and equipment together, GLM RM ANOVA was used to assess between- and within-participant differences during the study period. Time was the within-participant factor. Investigators performed statistical conversions of the ANOVA to effect sizes using Cohen’s criteria (1988). Investigators calculated effect sizes to give a direct illustration of the magnitude of effect. Doing so allowed for an assessment of the importance of a finding independent from the sample size. An alpha level of .05 was used for all statistical tests.
Investigators used linear regression to determine what percentage of the variance in hours of absence caused by back pain was due to depression (as measured by the Beck Depression Inventory [BDI]). If a participant had submitted only two sets of questionnaires, investigators used the SPSS function “Replace Missing Values” to insert the series mean to allow comparisons in time series; this function does not alter outcomes but enables a larger sample size for data analysis.
Not all participants completed all questionnaires: four dropped out of the IG during the course of the study because of schedule conflicts, relocation, or unrelated illness. Four of the CG participants did not complete questionnaires after randomization, citing competing time demands or loss of interest in the study (once they learned that they would not be offered the stress and pain management sessions immediately). During data analysis, one CG participant was dropped because she reported on the demographic questionnaire that she worked only 24 hours a week. The 12 IG participants who completed CBT attended an average of 5.3 sessions. There were 11 IG participants who completed both CBT and the ergonomics. There were 10 CG participants who completed the ergonomics-only intervention.
Of the 20 NAs and 11 RNs recruited, 31 were female. The average age was 41.9 years. They worked an average of 40.5 hours per week, with a mean shift length of 8.8 hours and an average length of employment at the facility of 5 years and 6 months. The majority worked the day shift, with 22.6% working evenings, 9.7% nights, and 9.7% rotating shifts. There were no statistically significant demographic differences between IGs and CGs at the beginning of the study (Table 1). At baseline, there were no statistically significant differences between IG and CG outcome measures other than one subscale of the PDI, for which the IG reported more disability (Table 2).
Hypothesis 1: Effect of CBT alone (IG compared with CG from M1 to M2).
Overall, both groups improved equally or were unchanged on most outcome measures (Table 3). The IG improved significantly more than the CG on two subscales of the PDI with large effect sizes and improved more than the CG on the PDI Global with a medium effect size.
Hypothesis 2: Effect of ergonomic intervention alone (CG at Measurement Time 2 compared with Measurement Time 1).
The CG showed significant improvement in VAS Pain Unpleasantness (paired t test: t2 = 2.55; p = .03) but not other measures. Investigators determined that asking participants to record daily equipment usage was not feasible because no participant returned all 6 weeks of Equipment Usage Logs.
Hypothesis 3: Effect of combined interventions (IG compared with CG overall).
Both groups showed a significant time effect for reduction in the PDI life support subscale, as well as VAS pain intensity, and VAS pain unpleasantness. The CG had a significant time x group effect for the PDI global and PDI family-home responsibilities subscale with large effect sizes (Table 4). Although the IGs had shown improvement at Measurement Time 2 in the PDI global, its scores reverted on this variable to baseline levels at Measurement Time 3. The IG showed large effect sizes for time by group in the PDI self-care and life-support subscales.
The BDI score at Measurement Time 2 accounted for a significant amount (50%) of the variance in hours absent caused by back pain (Table 5). However, BDI score at Measurement Time 1 did not.
Qualitative comments from participants about both the CBT sessions and the patient handling equipment were very positive. Comments reflected the desire that the group sessions “never end” and statements that the skills learned were “very useful.” Feedback about the equipment included that it was “the best for patient’s safety as well as reducing staff injuries.”
This pilot study demonstrated that offering CBT sessions for nursing personnel was feasible, judging from the IG’s high completion rate, the CG’s high attendance during the poststudy phase, and the positive comments of participants. CBT alone had a large effect size for reducing disability in self-care and life-support activities and a medium effect size for reducing disability in social activities. In the first phase, the CG subjects improved as much as the IG in several outcome measures, indicating the presence of a Hawthorne effect, possibly from having a forum for expressing pain emotions through the questionnaires and from interaction with the PI during screening interviews. After improvement, the reversion to baseline PDI global scores by the IG at Measurement Time 3 indicates the need for booster CBT training. The ergonomic intervention alone improved VAS Back Pain Unpleasantness in the CG. Both interventions together did not improve outcomes over either intervention alone. However, after 3 months of one or the other or both interventions, both groups had improved in measures of back pain intensity and unpleasantness and overall disability, indicating the need for further study of interventions for this problem.
PSS mean scores for both groups at the end of the study period were approximately 12 points higher than the norm of 13.7 for American females (Cohen & Williamson, 1988), indicating that these rehabilitation hospital direct-care providers perceived themselves as stressed. For comparison, direct-care providers in an acute care hospital had mean PSS scores similar to the care providers in this rehabilitation hospital (Menzel & Robinson, in press), indicating high levels of self-perceived stress may be common to direct-care providers regardless of setting.
Equipment and sessions were well received. The facility purchased most of the equipment and hired the psychologist to provide the sessions for all staff members. Many staff members had been unaware that modern equipment had replaced hand-pump hydraulic lifts with the use of motors, improved stability, shortened use time, and enhanced interfaces between the patient and the equipment. In addition, direct-care providers on the study units had been unaware before training of the many clinical opportunities to use patient handling equipment, such as friction-reducing devices. However, inconvenient storage of equipment was a barrier to use because the lifts were mobile and not ceiling mounted.
Although this pilot study had a small sample size and was underpowered to detect effectiveness of the interventions, it could indicate whether results were in the hypothesized direction. The study and the interventions were too short to determine their effect over time. Despite such limitations, this pilot accomplished its main purposes to assess feasibility and effect sizes in preparation for a larger study. Because other studies have demonstrated the value of patient handling equipment in reducing physical exposures and related injuries, future efforts will focus on reducing psychosocial stressors in hospitals that have already addressed ergonomic issues through the use of equipment and training. To increase attendance at CBT sessions (and thereby the effectiveness of the intervention), more classes will be offered at more times to accommodate the changing schedules of direct patient care providers. Also, the CBT sessions will be shortened to 1 hour but offered over a 9-week period. An instrument will be selected that measures job stress, which is one of the targets of CBT. The inclusion criteria will be broadened and strengthened to include musculoskeletal pain of moderate intensity in any body part for at least 1-week’s duration in the past month to reduce the number of participants reporting no current pain.
Several studies have shown the effectiveness of lifting equipment in acute care hospitals and nursing homes, but none in rehabilitation hospitals. Yet, nursing staff at rehabilitation hospitals are exposed to more frequent patient-handling activities than in either acute or long-term care facilities because of the high dependency levels of rehabilitation patients (i.e., the long stays and slow progress of dependent patients and the assistance they require to help them meet their mobility goals). Therefore, preventive approaches addressing a broad spectrum of causes are critically needed to protect the health of rehabilitation nursing staff.
Rehabilitation hospitals should provide sufficient lifting equipment to reduce the need for manual handling. Patient handling equipment, although expensive, pays for itself within a few years through savings in workers’ compensation costs (Collins, Wolf, Bell, & Evanoff, 2004). In a recent study, only 11% of hospital nurses reported using mechanical lifting devices routinely, with unavailability of equipment given as the primary reason (Byrns, Reeder, Jin, & Pachis, 2004). On the other hand, if a facility provides such equipment in adequate numbers and good working order, rehabilitation nursing staff should make it a habit to use it, for their safety and the safety of their patients. There is a primer of the types of modern equipment available at the Veteran’s Administration VISN 8 Patient Safety Center’s Web site: http://www.visn8.med.va.gov/patientsafetycenter/
Ceiling mounted lifts solve the equipment storage problem and provide the most convenience for direct patient care providers by ensuring that a lift is always nearby. Many rehabilitation patients are now equipping their homes with such devices, which provide them with a level of independence and reduce the risk of back injuries for their caregivers. Once patient handling equipment is in place, rehabilitation hospital administrators should consider a nonpunitive “low lift” policy that encourages care providers to use equipment wherever possible.
In addition to equipment purchases, rehabilitation hospitals should offer periodic training on their use and application. The VISN 8 Patient Safety Center provides helpful algorithms for assessing patients and selecting the correct type of handling equipment. Consider designating one staff member on each unit as a resource person who receives additional training in safe-patient handling. The VISN 8 Patient Safety Center holds an annual conference on this topic.
To evaluate the effectiveness of lifting equipment, safety committees should track trends in injury statistics internally and investigate musculoskeletal injuries caused by patient handling. In addition, a rehabilitation hospital may benchmark its injury rates against national data collected by the U.S. Bureau of Labor Statistics using the North American Industry Classification System (NAICS) code 622310 effective since 2003. If a rehabilitation facility has already reduced physical stressors through providing patient handling equipment but finds its back injury rates remain high, it should consider addressing psychosocial workplace stressors as well.
The positive relationship between scores on the BDI and hours of work absence points to the importance of psychosocial factors in disability. The size of this relationship was quite large (50%), and although it is assumed that the depression was related to, or the result of, the pain condition, this study design did not rule out other potential sources of the psychological distress. These results suggest that work absence might be reduced with successful treatment of either pain, depression, or both. Through these efforts, rehabilitation hospitals can preserve the working abilities of their staff members and enable them to continue caring for patients.
About the Authors
Nancy N. Menzel, PhD RN COHN-S, is an associate professor at the University of Nevada Las Vegas. Direct correspondence to her at University of Nevada Las Vegas, School of Nursing, 4505 Maryland Parkway, Box 453018, Las Vegas, NV 89154 or firstname.lastname@example.org.
Scarlett Lilley, BSN RN CRRN, is director of nursing, Brooks Rehabilitation Hospital, Jacksonville, FL.
Michael E. Robinson, PhD, is a professor at the University of Florida, College of Public Health and Health Professions, Gainesville, FL.
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