Tehran University Medical Journal

Background: Epidural fibrosis (EF) is a part of normal physiological tissue response to laminectomy and it may be an important cause of failed back surgery syndrome (FBSS). The objective of this study was to evaluate the effect of using gel foam after laminectomy on reduction of epidural fibrosis.

Methods: In this prospective study forty five rabbits were recruited. The cases undergone bilateral laminectomy at the L4 and L5 lumbar levels under an approved surgical protocol. After eight weeks the rabbits were sacrificed and the spinal segments from L3 to L6 were removed en bloc. The amount of scar tissue at the laminectomy defect was scored. The fibroblast and inflammatory cell counts were also compared between two groups.

Results: In this study 55% of group A rabbits were placed in grade 0 or I, grade II fibrosis could be detected in the remaining 45%. In group B these amounts were 73.7% and 26.3% respectively, which no significant statistical difference could be detected between two arms (p=0.189). Comparing the quantity of fibroblasts 40% of group A rabbits were recognized as grade I and the other 60% as grade II and grade I fibrosis was discovered in 42.1% of group B rabbits, while other 57.9% suffered from grade II fibrosis, again no significant statistical difference could be attributed between two arms (p=0.576). Also comparing inflammatory cell counts detected in the specimens no significant statistical difference could be detected either (p=0.465).

Conclusion: According to this study using gel foam during the laminectomy surgery in rabbits has no obvious effect in reducing post laminectomy epidural fibrosis after eight weeks of follow-up.