Little is known about the epidemiology of neuropathic pain in primary care patients consulting with low back-related leg pain. We aimed to describe prevalence, characteristics and clinical course of low back-related leg pain patients with and without neuropathic pain, consulting with their family doctor in the UK.
This was a prospective cohort study. Data were collected using a standardised baseline clinical examination and self-report questionnaires at baseline, 4, 12 and 36-months. We identified cases of neuropathic pain using three definitions: two based on clinical diagnosis (sciatica, with and without evidence of nerve root compression on MRI), one on the self-report version of Leeds Assessment for Neurological Symptoms and Signs (S-LANSS). Differences between patients with and without neuropathic pain were analysed comparing each definition. Clinical course (mean pain intensity measured as the highest of leg or back pain intensity: mean of three Numerical Rating Scales, each 0-10) was investigated using linear mixed models over 36-months.
Prevalence of neuropathic pain varied from 48% to 74% according to definition used. At baseline, patients with neuropathic pain had more severe leg pain intensity, lower pain self-efficacy, more patients had sensory loss than those without. Distinct profiles were apparent depending on neuropathic pain definition. Mean pain intensity reduced after 4-months (6.1 to 3.9 (sciatica)), most rapidly in cases defined by clinical diagnosis.
This research provides new information on the clinical course of neuropathic pain and a better understanding of neuropathic pain in low back-related leg pain patients consulting in primary care.

Author