Systematic literature review of spinal decompression via motorized traction for chronic discogenic low back pain.

OBJECTIVE: The objective of this study was to systematically review the literature to assess the efficacy of nonsurgical spinal decompression achieved with motorized traction for chronic discogenic lumbosacral back pain.
DESIGN: Computer-aided systematic literature search of MEDLINE and the Cochrane collaboration for prospective clinical trials on adults with low back pain in the English literature from 1975 to October 2005. Methodologic quality for each study was assessed. Studies were included if the intervention group received motorized spinal decompression and the comparison group received sham or another type of nonsurgical treatment.
RESULTS: Data from 10 studies were fully analyzed. Seven studies were randomized controlled trials using various apparatus types. Because of this low number, we also analyzed three nonrandomized case series studies of spinal decompression systems. As the overall quality of studies was low and the patient groups heterogeneous, a meta-analysis was not appropriate and a qualitative review was undertaken. Sample sizes averaged 121 patients (range 27-292), with six of the seven randomized studies reporting no difference with motorized spinal decompression and one study reporting reduced pain but not disability. The three unrandomized studies (no control group) of motorized spinal decompression found a 77% to 86% reduction in pain.
CONCLUSIONS: These data suggest that the efficacy of spinal decompression achieved with motorized traction for chronic discogenic low back pain remains unproved. This may be, in part, due to heterogeneous patient groups and the difficulties involved in properly blinding patients to the mechanical pulling mechanism. Scientifically more rigorous studies with better randomization, control groups, and standardized outcome measures are needed to overcome the limitations of past studies.