Neuropathic pain in low back-related leg pain patients: What is the evidence of prevalence, characteristics, and prognosis in primary care? A systematic review of the literature.

This systematic review synthesizes literature describing prevalence, characteristics and prognosis of low back-related leg pain (LBLP) patients with neuropathic pain in primary care and/or similar settings. Inclusion and exclusion criteria were developed and used by independent reviewers to screen citations for eligibility. The initial search yielded 24,948 citations; after screening 12 studies were included. Neuropathic pain was identified by case ascertainment tools (n=5), by clinical history with examination (n=4), and by LBLP samples assumed neuropathic (n=3). Neuropathic pain prevalence varied from 19% to 80%. There was consistent evidence for higher back-related disability (n=3), poorer health-related quality of life (n=2) and some evidence for more severe depression (n=2), anxiety (n=3) and pain intensity (n=4) in patients with neuropathic pain. Results were less consistent when cases were identified through clinical history plus examination than those identified using case ascertainment tools. Prognosis (n=1) of LBLP patients with neuropathic pain was worse compared to those without, in all outcomes (leg pain intensity, leg and back-related disability, self-reported general health) except back pain intensity. No studies described prognostic factors. This systematic review highlights the evidence gap in neuropathic pain in LBLP in primary care, especially with respect to prognosis. PERSPECTIVE: Patients with low back-related leg pain may have neuropathic pain. This systematic review emphasises the paucity of evidence describing the characteristics and prognosis of neuropathic pain in this patient population. Future research investigating prognosis of these patients with neuropathic pain is likely to contribute to better understanding and management