Efficacy of Poly(D,L-Lactic Acid-co-Glycolic acid)-Poly(Ethylene Glycol)-Poly(D,L-Lactic Acid-co-Glycolic Acid) Thermogel As a Barrier to Prevent Spinal Epidural Fibrosis in a Postlaminectomy Rat Model.
Experimental animal study.



The authors conducted a study to determine the efficacy and safety of the poly(D,L-lactic acid-co-glycolic acid)-poly(ethylene glycol)-poly(D,L-lactic acid-co-glycolic acid) (PLGA-PEG-PLGA) thermogel to prevent peridural fibrosis in an adult rat laminectomy model.



Peridural fibrosis often occurs after spinal laminectomy. It might cause persistent back and/or leg pain postoperatively and make a reoperation more difficult and dangerous. Various materials have been used to prevent epidural fibrosis, but only limited success has been achieved.



The PLGA-PEG-PLGA thermogel was synthesized by us. Total L3 laminectomies were performed on 24 rats. The PLGA-PEG-PLGA thermogel or chitosan (CHS) gel (a positive control group) was applied to the operative sites in a blinded manner. In the control group, the L3 laminectomy was performed and the defect was irrigated with the NS solution 3 times. All the rats were killed 4 weeks after the surgery.



The cytotoxicity of this thermogel was evaluated in vitro and the result demonstrated that no evidence of cytotoxicity was observed. The extent of epidural fibrosis, the area of epidural fibrosis, and the density of the fibroblasts and blood vessel were evaluated histologically. There were statistical differences among the PLGA-PEG-PLGA thermogel or CHS gel group compared with the control group. Although there was no difference between the PLGA-PEG-PLGA thermogel and CHS gel, the efficiency of the PLGA-PEG-PLGA thermogel was shown to be slightly improved compared with the CHS gel.



The biocompatibility of the PLGA-PEG-PLGA thermogel was proven well. The application of this thermogel effectively reduced epidural scarring and prevented the subsequent adhesion to the dura mater. No side effects were noted in the rats.
*Department of Orthopaedic Surgery, Zhongshan Hospital †State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Advanced Materials Laboratory, Fudan University, Shanghai, China.
Xiangqian
X
Li
Lin
L
Chen
Hong
H
Lin
Luping
L
Cao
Ji'an
J
Cheng
Jian
J
Dong
Lin
L
Yu
Jiandong
J
Ding
D000818:Animals; D001672:Biocompatible Materials / Q000627:therapeutic use*; D004195:Disease Models, Animal; D004824:Epidural Space / Q000473:pathology*; D005355:Fibrosis / Q000517:prevention & control*; D007796:Laminectomy / Q000009:adverse effects*; D008297:Male; D011092:Polyethylene Glycols / Q000627:therapeutic use*; D011098:Polyglactin 910 / Q000627:therapeutic use*; D011183:Postoperative Complications / Q000517:prevention & control*; D051381:Rats; D017207:Rats, Sprague-Dawley; D016896:Treatment Outcome
D001672:Biocompatible Materials; C528571:poly(lactic-co-glycolic acid)-polyethylene glycol-poly(lactic-co-glycolic acid); D011098:Polyglactin 910; D011092:Polyethylene Glycols