Schulung der Hebetechnik verbessert nicht das Auftreten von Rückenschmerzen

http://cme.medscape.com/viewarticle/569657

February 4, 2008 — A systematic review published in the February 1 Online First issue of the BMJ shows no evidence to support use of advice or training in lifting techniques in the workplace with or without lifting equipment to prevent back pain or consequent disability.

"Specific techniques have been advocated to reduce the load on the back," write Kari-Pekka Martimo, from the Finnish Institute of Occupational Health in Helsinki, Finland, and colleagues. "Earlier reviews on occupational interventions have questioned the role of education in the prevention of work related back pain. Even though primary studies have found no effect of training on the incidence of back pain, this could be incidental or caused by small sample size."

The goal of this systematic review was to determine whether advice and training regarding lifting techniques and use of lifting equipment prevent back pain in jobs that involve heavy lifting.

The investigators searched MEDLINE, EMBASE, CENTRAL, Cochrane Back Review Group's specialized register, CINAHL, Nioshtic, CISdoc, Science Citation Index, and PsychLIT from September through November 2005 for randomized controlled trials (primary search) and for cohort studies with a concurrent control group (secondary search).

Eligibility criteria for inclusion in the review were studies that evaluated interventions aimed to modify techniques for lifting and handling heavy objects or patients and that had primary outcomes of measurements for back pain, consequent disability, or sick leave. Two of the review authors independently determined study eligibility and methodologic quality of included studies.

Results of studies comparing similar interventions were summarized and combined in a meta-analysis with use of odds ratios and effect sizes. The review authors compared the conclusions of the primary and secondary analyses.

Of 6 randomized trials and 5 cohort studies meeting eligibility criteria, 2 randomized trials and all cohort studies were classified as high quality. Of the 11 included studies, 8 involved people whose occupations required lifting and moving patients, and 3 studies involved baggage handlers or postal workers. Participants in control groups in these studies received no intervention or minimal training, physical exercise, or use of back belts.

In the randomized trials, which enrolled a total of 17,720 participants, none of the comparisons yielded significant differences. Secondary analysis showed no significant results in any of the cohort studies (n = 772 participants) supporting the findings from the randomized trials.

"There is no evidence to support use of advice or training in working techniques with or without lifting equipment for preventing back pain or consequent disability," the review authors write. "Either the advocated techniques did not reduce the risk of back injury or training did not lead to adequate change in lifting and handling techniques. . . . The findings challenge current widespread practice of advising workers on correct lifting technique."

Limitations of this review were varied measurement of the outcomes in the primary studies, inability to extract the data needed from all studies, and the need to adjust the results of most of the studies for the effect of cluster randomization that was not considered by the authors of these studies.

"Many health professionals are involved in training and advising workers on lifting and handling," the review authors conclude. "Even though there may be other reasons to continue this practice, this review does not provide evidence that it prevents back pain. . . . We need a better understanding of the causal chain between exposure to biomechanical stressors at work and the subsequent development of back pain to enable the development of new and innovative ways to prevent back pain."

The Commonwealth of Australia as represented by and acting through the Department of Employment and Workplace Relations supported this review. The review authors have disclosed no relevant financial relationships.

In an accompanying editorial, Niels Wedderkopp, MD, PhD, from Funen Hospital in Funen, Denmark, and Dr. Charlotte Leboeuf-Yde, DC, MPH, PhD, from the University of Southern Denmark in Odense, Denmark, suggest that randomized clinical trials of nonspecific low back pain should be suspended because they include so many different types of back pain that the results are difficult to interpret.

"The commonly given advice to patients to stay at work and be as physically active as possible may not be appropriate for people whose work involves heavy lifting and who have a history of recurrent back pain and several periods of sick leave," Drs. Wedderkopp and Leboeuf-Yde write. "Continuing heavy manual work in their job and increasing leisure time physical activity may not be a good idea as no clearly effective treatment is available. A change of job and (prudently) staying active in daily life may be the best way for these patients to regain command of their back and their occupation."

Drs. Wedderkopp and Leboeuf-Yde have disclosed no relevant financial relationships.

BMJ. Published online February 1, 2008.

Clinical Context

Back pain is highly prevalent, and heavy lifting at work is a risk factor for back pain. Optimal lifting techniques are often advocated to prevent back pain, and lifting equipment has been developed to relieve workload. However, reviews of occupational interventions have questioned the effectiveness of education on lifting in the prevention of back pain, and many primary studies have shown limited or no effect of training on back pain.

This is a systematic review of randomized clinical trials and cohort studies to examine the effect of training vs no training on the incidence of back pain and related disability.

Study Highlights

• The investigators conducted a literature search of multiple databases including MEDLINE, EMBASE, CENTRAL, CINAHL, and Nioshtic in any language to identify articles in which lifting technique was used as an intervention, and outcomes included back pain measures, disability, or sickness absence.
• 2 independent reviewers identified studies, and 2 other reviewers assessed methodologic quality using criteria of the Cochrane Back Review Group.
• Primary articles identified were randomized controlled trials, and secondary articles were cohort studies with a concurrent control group.
• Studies were categorized by follow-up duration as short-term (< 3 months), intermediate
  (3 - 12 months) and long-term (> 12 months).
• Effect sizes were combined for studies that measured similar outcomes such as sickness absence rate or disability score at similar follow-up times with use of the generic inverse variant method.
• 3547 articles were identified with the primary search strategy for randomized controlled trials; 101 were evaluated.
• 11 studies including 4 cluster randomized trials, 2 individual randomized trials, and 5 cohort studies were analyzed.
• 2 randomized control trials and all cohort studies were considered high quality.
• In the eligible randomized trials, the total number of participants was 17,720, but after adjustment for unit of analysis error, the effective sample size was 2727.
• 3 randomized control trials and all 5 cohort studies involved people whose occupations required care of patients.
• 1 article studied postal workers and 2 articles studied baggage handlers.
• The number of participants in randomized trials ranged from 51 to 12,772, and follow-up ranged from 6 months to 5.5 years.
• In the cohort studies, the number of participants ranged from 45 to 345, and follow-up ranged from 8 weeks to 2 years.
• The training interventions focused on lifting techniques, with duration ranging from 1 session to once a week for 2 years.
• In 3 studies, the intervention was supported by follow-up and feedback at the workplace.
• The advocated lifting techniques were not described in detail in the studies.
• 3 studies involved supervisors, and 5 studies encouraged participants to use available lifting aids.
• Most studies used a professional instructor for education.
• 5 studies monitored compliance with instruction and use of lifting techniques and equipment.
• Results indicated positive change in lifting techniques in 3 studies and marginal or no change in 2 studies.
• 1 study reported improvement in knowledge but not lifting techniques or handling heavy objects.
• Comparison between groups that received training vs those that did not in the randomized trials showed no significant difference in back pain or related disability at intermediate or long-term follow-up.
• Results of 3 cohort studies showed similar outcomes in the short-term and long-term.
• 1 trial showed no effect of training on back pain vs no advice, and 2 cohort studies showed no effect of training vs less extensive training.
• 1 study found no advantage of training vs exercise for intermediate follow-up.
• Overall, training with or without lifting equipment showed no difference in outcomes of back pain, disability, or back injury.
• The authors suggested that a better understanding of the causal relationship between exposure to biomechanical stressors and subsequent back pain was needed to develop new methods to prevent back pain.

Pearls for Practice

• Training to improve lifting techniques is not associated with a reduced incidence of back pain.
• Training to improve lifting techniques on behavior is not consistent and, overall, does not have an impact on back pain outcomes