Epidural fibrosis (EF) is defined as nonphysiologic scar formation, usually at the site of neurosurgical access into the spinal canal, in intimate vicinity to and around the origin of the radicular sheath. From the very onset, EF behaves as a reparative inflammation causing, as a rule, symptoms of characteristic nature and clinical course (pain). Treatment of epidural fibrosis causing failed back surgery syndrome (FBSS) by neuromadulation technique is very expensive. Finding of suitable parameters for the indication of treatment is very important.
We studied a cohort of the dorsal column stimulation to 50 patients with history of failed back surgery syndrome coupled with epidural fibrosis. Percutaneus implantation technique was used in 48 patients. Study group is composed by 20 women and 28 men aged 26-67 years (mean age 49). Two patients had no effect during the examination period. Prospective observational questionnaire based study was used. The results were processed relative to the clinical finding, subjective intensity of complaints rated on a visual-analogue scale (VAS) and graphic finding (degrees of epidural fibrosis – Ross classification).
II. Assessment of the EF and Δ VAS correlation after neuromodulation: as cross-tabulation suggests, there was a statistically significant correlation between the degree of fibrosis and Δ VAS after implantation at the 5% level of significance. As for linear association, a significant correlation was found at the 5% level of significance.
The extent of epidural fibrosis is an important factor for FBSS. FBSS is the basis for the existence of neuropathic pain after lumbar spine surgery. There is a clear evidence of a correlation between the MR degree of epidural scar formation and the effect of dorsal column stimulation. The stimulation in patients without postoperative epidural fibrosis is less effective. This is important factor to indication of patients for spinal cord stimulation. Previous spinal fixation is also the statistically significant factor for a bad result of the neuromodulation. Other factors such as instability, Modicchanges or spinal stenosis are less statistically significant.P34/LF1/7