title: The prevention effect of poly (L-glutamic acid)/chitosan on spinal epidural fibrosis and peridural adhesion in the post-laminectomy rabbit model.
abstract: OBJECTIVE
  Spinal epidural fibrosis and adhesion are implicated as one of the key factors of failed back surgery syndrome, which may cause dura mater compression or peridural tethering, resulting in persistent backache and leg pain. Various materials or drugs have been used to inhibit formation of epidural fibrosis and reduce the compressive effect on neural structures. Nevertheless, the effects are not satisfied. In this study, we investigated the prevention effect of poly (L-glutamic acid)/chitosan (PLGA/CS) barrier on epidural fibrosis developing post-laminectomy in a rabbit model.
  
  
  METHODS
  Sixteen rabbits were divided randomly into two equal groups: group A (experimental group, n = 8) and group B (non-treatment group, n = 8). In both groups, total L5-6 laminectomy was performed; further both ligamentum flavum and epidural fat were removed gently. In experimental group, the laminectomy sites were treated with PLGA/CS barriers, while no additional treatment was received in non-treatment group. At 1, 12 and 24 weeks post-surgery, the animals were subjected to magnetic resonance imaging (MRI) evaluation. Following last MRI examination, all rabbits were sacrificed and their spinal columns were totally removed for further macroscopic and histological evaluation.
  
  
  RESULTS
  MRI showed that rabbits treated with PLGA/CS barrier at 12 and 24 weeks post-surgery had less epidural fibrosis or scar tissue, peridural adhesion, foreign body reaction and low pressure of spinal cord in comparison with the non-treatment group. In consistence with the radiographic results, macroscopic analysis and histological examination showed that the amount of scar tissue and the extent of epidural adhesion decreased significantly in experimental groups. Concerning the fibroblast density evaluated, the scores were significantly lower in experimental group compared with those in non-treatment group.
  
  
  CONCLUSIONS
  The results of our study demonstrate that PLGA/CS barrier is effective in inhibiting epidural fibrosis and peridural adhesions in post-laminectomy rabbit model.
authors.affiliation: Department of Orthopedic Surgery, Zhongshan Hospital, Fudan University, Feng Lin Road No. 180, XuHui District, Shanghai, 200032, People's Republic of China.
authors.forename: Chunbo
authors.initials: C
authors.lastname: Li
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.forename: Haifei
authors.initials: H
authors.lastname: Liu
authors.forename: Jingbo
authors.initials: J
authors.lastname: Yin
authors.forename: Lei
authors.initials: L
authors.lastname: Cui
authors.forename: Zenggan
authors.initials: Z
authors.lastname: Chen
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology*; D002452:Cell Count; D048271:Chitosan / Q000494:pharmacology*; D004195:Disease Models, Animal; D004824:Epidural Space / Q000473:pathology*; D005347:Fibroblasts / Q000378:metabolism; D005355:Fibrosis; D005549:Foreign-Body Reaction / Q000517:prevention & control; D007796:Laminectomy; D008279:Magnetic Resonance Imaging; D011099:Polyglutamic Acid / Q000494:pharmacology*; D019736:Prostheses and Implants; D011817:Rabbits; D000267:Tissue Adhesions / Q000517:prevention & control
chemical_list: D001672:Biocompatible Materials; D011099:Polyglutamic Acid; D048271:Chitosan