What is the evidence that neuropathic pain is present in chronic low back pain and soft tissue syndromes? An evidence-based structured review.

OBJECTIVES The objectives of this evidence-based review were to review the evidence for whether neuropathic pain (NP) is associated with chronic low back pain (CLBP) and soft tissue syndromes (STS), and review the reported prevalence percentages for NP within these syndromes. METHODS Of 816 reports, 11 addressed the diagnosis of NP in CLBP and five of NP in STS. Studies were grouped by the method of arrival at an NP diagnosis, e.g., physical examination, type of NP inventory utilized, etc. The reported prevalence of NP was determined by aggregating all the patients in all the studies in each grouping. Similarly, the reported prevalence of NP within CLBP and STS was determined by aggregating all the patients with NP from all the studies in those groups. Each study was independently rated by two raters according to 11 quality criteria generating a quality score. The strength and consistency (SAC) of the evidence represented by each grouping was rated according to Agency for Health Care Policy and Research guidelines. RESULTS In each grouping, 100% of the studies reported some prevalence of NP (none reported zero prevalence). Aggregated NP prevalence for CLBP was 36.6% (SAC level A [consistent multiple studies]) and for STS 41.1% (SAC level A). There was significant variation in prevalence according to the method utilized to diagnose NP. CONCLUSION There is consistent evidence by all methods that NP is present in CLBP and STS. Reported prevalence percentages by all methods are substantial. This has significant implications for the treatment of CLBP and STS.