Study Purpose. To examine the presence of radicular pain and its relationship to the degree of lumbar nerve root compression in patients with a degenerative lumbar spine condition about to undergo surgery for either lumbar disc prolapse or lumbar canal stenosis. Background. The pathophysiology underlying radicular pain is not completely understood but it is thought that nerve root compression is a key factor and from a surgical perspective, decompressing the nerve root is considered to be the key therapeutic step. However, despite often severe root compression in patients with lumbar stenosis, radicular pain is not a typical feature. Methods. Thirty-nine pre-surgical patients with either lumbar disc prolapse or lumbar canal stenosis were studied using the Standardised Evaluation of Pain (StEP), a clinical assessment tool known to predict with a high degree of sensitivity and specificity the presence or absence of lumbar radicular pain. A nerve root compression score was given from lumbar MRI for each patient by a neuroradiologist blinded to the patients history. Results. The StEP assessment tool was able to distinguish the presence or absence of radicular pain with high sensitivity and specificity. This correlated well with the pre-operative diagnosis of disc prolapse or canal stenosis. The relationship between radicular pain and nerve root compression was less clear and will be discussed. Conclusion. This study confirms StEP as a useful bedside tool for identifying the presence of radicular pain in patients with a degenerative lumbar spine condition. Nerve root compression per se does not necessarily produce radicular pain. Conflicts of Interest. None. Source of Funding. None. This study has not been published or presented at a previous meeting