The Empirical Study On Poly Lactate Glycolic Acid (plga) Membrane In Prevention Of Epidural Scar Adhesions After Operation

Objective We want to approach the prophylactic function of PLGA membrane in prevention of epidural and nerve root scar adhesions after laminectomy.Methods We excised the L6 vertebral plates of 48 adult New Zealand male rabbits, exposing spinal dura mater by 12mmx6mm, to make vertebral plate excision model. Probe the nerve root. Then divided them into 4 groups according to different materials:PLGA membrane glue (group A), gelatin sponge (group B), bioproten glue (group C) and saline solution (group D). We observed clinic events of the rabbits everyday. We sacrificed 6 rabbits for each group on 2 and 8 weeks after operation, took out of L6-L7 completely, then observed the morphological changes of the samples grossly, measured the adhesions level according to Lawson'standard; measured the orbit of the nerve root by mini-rafah pressure sensor and digital electronic dynamometer; after HE staining, epidural fibroblast,inflammatory cell infiltration and the scope of scar tissue adhesions were observed, and graded in accordance with the extent of adhesions.Results All the 48 rabbits were available for analysis.①Gross observation:Spinal dura mater and nerve roots didn't adhere with peripheral hematoma and scar at 2 and 8 weeks in group A, dural sac and nerve roots were't compressed obviously either. Dura mater and nerve roots adhered slightly with peripheral hematoma at 2 weeks in group B,C and D, but were't compressed obviously; The scar became harden, the adhesions were obvious and difficult to separate at 8 weeks, and the sac was compressed to deform.②Orbit of the nerve roots:Group A surpassed group B,C and D at 2 and 8 weeks; Group C and D surpassed group B at 8 weeks.③Histological observation:PLGA membrane formed intact physic barrier to protect the dural sac and nerve root from been dragged,adhered and pressed by scar at 2 weeks in group A; And there were no epidural adhesions at 8 weeks,and the inflammatory response reduced Significantly. The gelatin sponge still existed at 2 weeks in group B and C, and the hematoma was surrounded by lots of collagen fibers secreted by fibroblasts; Residual gelatin sponge filled mesh of connective tissue at 8 weeks, dural sac and nerve roots adhered seriously with surrounding tissue. In group D, dura mater adhered extensively with dorsal tissue, and the inflammatory reaction was obviously.④Statistical analysis with SPSS 13.0 found that there were significant deviations between Group A and other groups (P<0.05); but no significant deviation between Group B,C and D (P>0.05). Conclusion In this experiment we use PLGA membrane prevent epidural and nerve roots adhesions after laminectomy indicated that, PLGA membrane can reduce epidural and nerve roots adhesions with surrounding scar obviously, and the clinical application prospects is bright; But if use gelatin sponge or bioprotein gel separately, it will do no good.