Background and Aims. Transforaminal epidurals (TFEs) have been widely used as a treatment for lumbar radicular pain since its introduction by Krempen and Smith in 1974. 1. Originally used as a diagnostic tool, it is now becoming increasingly recognised as a definitive treatment. 2. This study investigates the use of TFEs by a single surgeon over 4 years. We hoped that the study would add to our understanding and the discussion of the actual benefit of therapeutic steroid and local anaesthetic injections by this route. 3. . Methods and Results. A total of 181 patients were identified. At injection 10mls 0.25% Marcaine and 40mg Depomedrone was injected under fluoroscopic guidance. Clinic notes and MRI reports for all patients were reviewed. Of the 176 patients included in the study, 127 showed a symptomatic improvement. Of these patients, 59 proceeded to surgical decompression. For 50 patients, TFE was the definitive treatment. 13 patients were offered but declined surgery. 5 patients were too frail to proceed to surgery. 49 patients showed no symptomatic improvement. Of this group, 34 were deemed unsuitable for surgical intervention. 15 patients did proceed to surgery. Conclusions and Discussion. These results are comparable to other similar case series. Vad et al. 3. demonstrated that 78% of patients studied were satisfied with the outcome of TFE. Riew et al. 2. showed that 53% of their study group avoided surgery due to positive long term effect of TFE. The operative notes of the 15 patients who proceeded to surgery despite a negative TFE outcome are being reviewed and will be presented. Conflicts of Interest. None. Source of Funding. None

A rat model of lumbar root constriction with an additional sympathectomy in some animals was used to assess whether the sympathetic nerves influenced radicular pain. Behavioural tests were undertaken before and after the operation.

On the 28th post-operative day, both dorsal root ganglia and the spinal roots of L4 and L5 were removed, frozen and sectioned on a cryostat (8 μm to 10 μm). Immunostaining was then performed with antibodies to tyrosine hydroxylase (TH) according to the Avidin Biotin Complex method. In order to quantify the presence of sympathetic nerve fibres, we counted TH-immunoreactive fibres in the dorsal root ganglia using a light microscope equipped with a micrometer graticule (10 x 10 squares, 500 mm x 500 mm). We counted the squares of the graticule which contained TH-immunoreactive fibres for each of five randomly-selected sections of the dorsal root ganglia.

The root constriction group showed mechanical allodynia and thermal hyperalgesia. In this group, TH-immunoreactive fibres were abundant in the ipsilateral dorsal root ganglia at L5 and L4 compared with the opposite side. In the sympathectomy group, mechanical hypersensitivity was attenuated significantly.

We consider that the sympathetic nervous system plays an important role in the generation of radicular pain.

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