PMID- 26924131 OWN - NLM STAT- MEDLINE DCOM- 20161017 LR - 20220310 IS - 2047-783X (Electronic) IS - 0949-2321 (Print) IS - 0949-2321 (Linking) VI - 21 DP - 2016 Feb 29 TI - Minimal invasive annulotomy for induction of disc degeneration and implantation of poly (lactic-co-glycolic acid) (PLGA) plugs for annular repair in a rabbit model. PG - 7 LID - 10.1186/s40001-016-0202-4 [doi] LID - 7 AB - BACKGROUND: The rabbit disc model is useful for the study of intervertebral disc (IVD) degeneration and experimental therapeutic interventions. The annulotomy-induced disc models present several drawbacks, particularly an excessive disruption of disc integrity and a rapidly disc degeneration; therefore, this study sought to establish a minimal invasive annulotomy for induction of disc degeneration model, combined to annulus repair using implantation of a PLGA (poly lactic-co-glycolic acid) plug. METHODS: New Zealand white rabbits (n = 24) received annular injuries in three discs (L3/4, L4/5 and L5/6). The experimental discs were randomly assigned to four groups: (a) annular defect with a 1.8 mm diameter mini-trephine; (b) annular puncture by 16G needle; (c) annular defect with a PLGA plug implanted by press-fit fashion; (d) uninjured L2/3 disc served as control. Postsurgical x-ray, MRI examination, and real-time PCR analysis were performed at 1, 3 and 6 months. Gross morphology and histology were evaluated at postoperative 6 months. RESULTS: Radiographic examinations showed a slow, progressive disc space narrowing and a significant degree of disc degeneration on MRI grade in the injured discs at 6 months in all rabbits. Histological examinations and aggrecan, Col1A1, Col2A1 and matrix metalloprotease (MMP)-3 mRNA expression confirmed the disc degeneration, supporting the imaging results. The PLGA implantation reduced the marked loss of T2-weighted signal intensity seen at MRI in the injured discs and slowly decreased the disc height index (DHI) over the follow-up period. HE/Safranin O staining showed that annular defect was replaced by regenerated connective tissue with significant loss of proteoglycan content. CONCLUSIONS: The minimally invasive approach for the creation of annular defects by an appropriately sized mini-Trephine is a suitable option for the study of disc degeneration in a rabbit model. Implantation of a suitable PLGA plug induced a successful repair of the annulus fibrosus within the degenerated disc, and retarded the degenerative process in the annular injury model. FAU - Xin, Long AU - Xin L AD - Clinical Laboratory, Department of Orthopedics, Tongde Hospital of Zhejiang Province, Hangzhou, China. xinlonghz@gmail.com. FAU - Zhang, Chun AU - Zhang C AD - Clinical Laboratory, Department of Orthopedics, Tongde Hospital of Zhejiang Province, Hangzhou, China. xinlonghz@aliyun.com. FAU - Zhong, Fuhua AU - Zhong F AD - Clinical Laboratory, Department of Orthopedics, Tongde Hospital of Zhejiang Province, Hangzhou, China. walker2004@sohu.com. FAU - Fan, Shunwu AU - Fan S AD - Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China. racer2004@sina.com. FAU - Wang, Wei AU - Wang W AD - Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China. wwgfz@tju.edu.cn. AD - Department of Polymer Materials Science and Engineering, Tianjin University, Tianjin, China. wwgfz@tju.edu.cn. FAU - Wang, Zhenbin AU - Wang Z AD - Clinical Laboratory, Department of Spine Surgery, The Fourth Affiliated Hospital of Xinjiang Medical University, Urumqi, 830000, China. wangzb0202@163.com. LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20160229 PL - England TA - Eur J Med Res JT - European journal of medical research JID - 9517857 RN - 0 (Aggrecans) RN - 0 (Biocompatible Materials) RN - 0 (Collagen Type I) RN - 0 (Collagen Type II) RN - 1SIA8062RS (Polylactic Acid-Polyglycolic Acid Copolymer) RN - 26009-03-0 (Polyglycolic Acid) RN - 33X04XA5AT (Lactic Acid) RN - EC 3.4.24.17 (Matrix Metalloproteinase 3) SB - IM MH - Aggrecans/genetics MH - Animals MH - Biocompatible Materials/pharmacology MH - Collagen Type I/genetics MH - Collagen Type II/genetics MH - Disease Models, Animal MH - Diskectomy/adverse effects/instrumentation/methods MH - Gene Expression/drug effects MH - Humans MH - Implants, Experimental MH - Intervertebral Disc/*drug effects/injuries/metabolism MH - Intervertebral Disc Degeneration/diagnostic imaging/*drug therapy/etiology MH - Lactic Acid/*pharmacology MH - Magnetic Resonance Imaging MH - Matrix Metalloproteinase 3/genetics MH - Minimally Invasive Surgical Procedures/adverse effects/instrumentation/methods MH - Polyglycolic Acid/*pharmacology MH - Polylactic Acid-Polyglycolic Acid Copolymer MH - Rabbits MH - Radiography MH - Random Allocation MH - Reverse Transcriptase Polymerase Chain Reaction PMC - PMC4770696 EDAT- 2016/03/01 06:00 MHDA- 2016/10/19 06:00 PMCR- 2016/02/29 CRDT- 2016/03/01 06:00 PHST- 2015/07/30 00:00 [received] PHST- 2016/02/11 00:00 [accepted] PHST- 2016/03/01 06:00 [entrez] PHST- 2016/03/01 06:00 [pubmed] PHST- 2016/10/19 06:00 [medline] PHST- 2016/02/29 00:00 [pmc-release] AID - 10.1186/s40001-016-0202-4 [pii] AID - 202 [pii] AID - 10.1186/s40001-016-0202-4 [doi] PST - epublish SO - Eur J Med Res. 2016 Feb 29;21:7. doi: 10.1186/s40001-016-0202-4.