Abstract
To analyse if patients with pain improvement following a nerve root block had better outcomes following lumbar microdiscectomy.
Fifty-six patients who had a lumbar microdiscectomy were retrospectively followed up to 1 year. All patients had a selective nerve root block (SNRB) as a primary treatment or diagnostic procedure. VAS pain scores were measured daily for 1 week following injection. Patients were grouped into responders and non-responders at 1 week. The 2 groups of patients were followed at 1 year following a lumbar microdiscetomy (LMD).
A total of 118 patients had SNRB over a period of 3 years. Of the 56 patients studied retrospectively, 52% and 36% of patients had a VAS score improvement of more than 2 points at 4 days and 1 week respectively. At 1 year post op, 85% of patients had better outcomes in the responder group compared to 74% in the non responder group. Although there was a difference this was not statistically significant.
Improvement with SNRB is not a positive predictor of good response with surgery. The ability to evaluate the effect of diagnostic or therapeutic blocks on surgical outcomes is limited by a lack of randomized studies and wide-ranging discrepancies with regard to injection techniques, surgical technique, and outcome measures. More research is needed to determine if diagnostic screening blocks can improve surgical outcomes.