Perceived knowledge suggests that patients with Failed Back Surgery and a poor psychological profile would respond poorly to surgical interventions. This comparative study was designed to identify if there was a significant difference in the outcome following endoscopic spinal intervention in patients with Failed Back Surgery when compared to those who had no previous interventions. Between April 1997 and November 1998, 54 patients with failed open back surgery and 85 without previous interventions were included in the study, underwent aware state pain source identification and endoscopic foraminal interventions. Pre- and post-operative assessment at 2 years was made using the Distress and Risk Assessment Method (DRAM), Oswestry Disability Index (ODI) and a Visual Analogue Pain Scale (VAPS). A Mann-Whitney U and Wilcoxon-Signed Rank tests were performed. Patients with failed back surgery demonstrated greater psychological distress, disability (p <
0.05) and pain pre-operatively than those who underwent primary endoscopic interventions. Post-operatively both groups demonstrated significant improvement and no difference was found in the Zung, DRAM, ODI and VAPS scores. With aware state pain source identification, targeted minimal intervention and discrete tissue ablation patients with failed back surgery with associated depression can demonstrate favourable physical and psychometric outcomes.
Introduction of new surgical intervention need assessment of the true results by eliminating cognitive dissonance and the placebo effect. Significant time must elapse since the procedure to derive conclusions. With the initial gratifying results of Endoscopic Foraminoplasty a retrospective analysis of the data was performed to identify if the outcome was accurate and not a placebo effect. Early postoperative Data (6 weeks and 6 months) derived from questionnaires on 91 patients with Endoscopic Foraminoplasty (April 1997 and November 1998), which included the Oswestry Disability Scale and a Visual Analogue Pain Scale was compared with the data at 2 years (late). A t-test was used to assess the difference between the Oswestry Disability scores from the two questionnaires and a Wilcoxon Signed Rank test for the Visual Analogue Pain Scale. No significant difference between the Visual Analogue Pain Scores at 6 weeks to 6 months and 2 years post-operation was noted. There was however, a marginal improvement (p= 0.05) in Oswestry Index over two years period. The initial outcome of Endoscopic Laser Foraminoplasty was sustained or improved at the end of two years and was not a placebo effect.
The view that patients low back pain presenting with ‘abnormal’ psychometric and poor DRAM scores predict an unsatisfactory surgical outcome is considered controversial. This prospective study was designed to identify if DRAM Scores (Scores of Distress Risk Assessment Method) is a predictive determinant or a reactive instrument in regard to the outcome of Endoscopic Foraminoplasty. One hundred and eighty-five patients (86 males and 99 females) underwent an Endoscopic Laser Foraminoplasty between April 1997 and November 1998. Pre- and postoperative assessment at 2 years was made using the Oswestry Disability Scale, and the Visual Analogue Pain Scale and the DRAM scores. Patients were categorised by their pre-op DRAM score. A Kruskal-Wallis analysis of variance and a regression analysis were performed. There was significant improvement in disability and pain scores at two years. (p<
0.05). A significant difference in median DRAM between the preoperative and postoperative score at two years was noted. While the DRAM score predicted the patients’ disability and pain it failed to predict the change in outcome. The DRAM score highlights individuals in distress who may need psychological support and physical treatment for optimum benefit from endoscopic spinal intervention and not be used to deny a surgical intervention.
