As with most orthopaedic injuries, the greatest risk factor for developing low back pain (LBP) is a history of low back injury. Because of this, an initial injury to the lumbar spine may develop into a long history of dealing with recurrent bouts of pain and reduced function that emanate from a spine injury. Therefore, investing in intervention programs to prevent the initial occurrence of LBP may have a greater impact than trying to optimize rehabilitation techniques. Primary (attempting to reduce the first-onset of LBP) or secondary (attempting to reduce recurrent LBP) prevention programs are designed to modify risk factors that are predictive of, or related to, the onset of LBP. Low back injury prevention programs have been designed and implemented to improve core strength, flexibility, or improve ergonomics of work-based demands, yet results have been mixed. Identifying the predictive risk factors of LBP is paramount to optimize primary and secondary prevention programs and ultimately reduce the onset and associated limitations of LBP.
My colleagues, Dr. Adam Goode (Duke University), Dr. Steven George (University of Florida), Dr. Chad Cook (Walsh University) and I recently performed and published a systematic review and meta-analysis which pooled together all previous literature in an attempt to identify both physical and psychological risk factors that have been consistently associated with the onset of first-time and recurrent LBP [1]. We searched for studies that used a population of either community-dwelling or occupation-based individuals that were pain-free at the start of the trial, with a portion that eventually developed LBP. Our systematic search strategy identified 41 previous studies to include in the review, yet of the 41, only 6 (3 community-dwelling and 3 occupational-based) of the studies included a population of individuals who had never previously experienced LBP (first-time LBP). In all four population groups that we studied, (community-dwelling first-time LBP, occupational-based first-time LBP, community-dwelling recurrent LBP, and occupational-based recurrent LBP) the incidence rate of LBP was approximately 25%, which is probably explained by the significant heterogeneity (variety of studies, research methods, and sample sizes), yet speaks to the significant problem of LBP in all populations.
Although we attempted to identify specific risk factors predictive of LBP, the results of the 41 studies were difficult to pool together because of the variety of risk factors studied and differing results. We were unable to draw any substantive conclusions about physical or psychological factors that lead to the biggest risk of LBP; however, there are some risk factors worth mentioning here. In general, women appeared more at risk than men. Specifically, women who stand and walk for > 2 hours a day were at higher risk than those who sit > 2 hours per day (but this does not necessarily mean that sedentary is better!). Individuals who perceived their job to be monotonous or require heavy lifting were more prone to developing LBP, especially compared with those who socially enjoyed work and had a confidante in their workplace. Yet the biggest take-home message from our study was that the most consistent risk factor for LBP was a history of LBP, with higher severities of previous injury leading to higher risk of future injury.
Though the results of our study do not allow us to make any specific recommendations toward the design of primary and secondary prevention programs, they do signify that considerable more work needs to be done in this area. They also suggest that LBP is probably multi-factorial and that no single specific intervention (e.g. core strength, flexibility training) should predominate in injury prevention programs: both physical and psychological factors may need to be addressed.
About Jeff Taylor
Jeff Taylor is an Assistant Professor, Director of Clinical Education, and member of the Human Biomechanics and Physiology Laboratory at High Point University, in High Point, North Carolina, USA. Clinically, Dr. Taylor is a Board-Certified Clinical Specialist in the areas of both Orthopaedic and Sports Physical Therapy. His current research focuses on the prevention of orthopaedic and sports injuries, most specifically of the knee (ACL), ankle and spine.
Reference
[1] Taylor JB, Goode AP, George SZ, & Cook CE (2014). Incidence and risk factors for first-time incident low back pain: a systematic review and meta-analysis. Spine Journal PMID: 24462537