There was no reduction in the rate of low back injury; no reduction in the median cost per injury; no reduction in the time off from work, or in the rate of repeated injury after return to work.
"Back schools" are proliferating: those health programs developed to provide employees in industry and business with the knowledge of safe lifting and handling techniques, good posture, and basic back anatomy to help them prevent on-the-job back injuries. An employer signs on for a back program with the theory that such preventive measures will help save the company the costs of lost man hours and workers' compensation claims. What employers may not know is that low back injuries comprise 15-25 percent of workers' compensation claims, and 30-40 percent of workers' compensation payments.1
While lifting and handling techniques commonly taught in back schools have shown reductions in the number and severity of back symptoms,2,3 the results of controlled clinical trials on back schools have been inconclusive.4
A recently published, randomized, controlled trial5 on a program to prevent low back injuries has attempted to clarify the effectiveness of back schools. The study involved approximately 4,000 postal workers over a five-year period (Sept. 1985 to Sept 1990). Twelve staff PTs and two senior therapists trained the intervention groups (2,534 workers and 134 supervisors) in "primary prevention."
A survey of the subjects was done half way through the five year study, which found "significant increases in knowledge of safe behavior among workers in the intervention groups," compared to the control group, "but no significant improvements in actual behavior... or significant reductions in the proportion of workers with tired backs."
The Numbers
The six month follow-up after the five year study showed a yearly rate of 21.2 injuries per 1,000 workers (as compared to 24 injuries per 1,000 before the prevention program). Acute low back pain/strain accounted for 93% of the injuries; 85% of the injuries were due to lifting and handling.
What was not expected was that injury rates were higher in the intervention group than in the control group. The authors suggested that this may have been due to "increased acceptability of reporting injuries" in the intervention group.
The study's authors concluded:
- ".... back schools are not by themselves an effective intervention for the primary prevention of industrial low back injury."
- that training had "no significant effect on rates of primary low back injury, on time off from work, on costs associated with injury, or on time elapsed until a further injury."
While the back injury prevention program made the subjects more knowledgeable about back safety, the training did not translate into the kind of tenable results employers seek. There was no reduction in the rate of low back injury; no reduction in the median cost per injury; no reduction in the time off from work, or in the rate of repeated injury after return to work.
It would be interesting to see the outcome of an identical, randomized controlled trail that had a back school program designed and administered by DCs, instead of the PTs, as in this study.
References
- Klein BP, Jense RC, Sanderson LM. Assessment of workers' compensation claims for back strains/sprains. J Occup Med, 1984;26:443-8.
- Mattmiller AW. The California Back School. Physiotherapy, 1980;66:118-21.
- Ayoub MA. Control of manual lifting hazards. Preemployment screening. J Occup Med, 1982;24:751-61.
- Keijsers J, Steenbakkers M, Meertens RM, Bouter LM, Kok G. The efficacy of the back school; a randomized trail. Arthritis Care Res, 1990;3:204-9.
- Daltroy lH, Iversen MD, Larson MG, Lew R, Wright E, Ryan J, Zwerling C, Fossel AH, Liang MH. A controlled trial of an educational program to prevent low back injuries. N Engl J Med, 1997;337:322-8.
