title: Negative Outcomes of Poly(l-Lactic Acid) Fiber-Reinforced Scaffolds in an Ovine Total Meniscus Replacement Model.
abstract: Our objective was to test the efficacy of collagen-hyaluronan scaffolds reinforced with poly(l-lactic acid) (PLLA) fibers in an ovine total meniscus replacement model. Scaffolds were implanted into 9 sheep (n = 1 at 8 weeks, n = 2 at 16 weeks, n = 3 at both 24, 32 weeks) following total medial meniscectomy. From 16 weeks on, explants were characterized by confined compression creep, histological, and biochemical analyses. Articular surfaces were observed macroscopically and damage was ranked histologically using the Mankin score. At sacrifice, three of the nine PLLA scaffolds had completely ruptured, and the intact scaffolds experienced progressive shape changes and severe narrowing in the body region at 16, 24, and 32 weeks. Aggregate compressive modulus and permeability did not improve with time. Histological and biochemical analyses showed significantly less extracellular matrix and less matrix organization compared to native tissue. Osteophytes, bone erosion, and cartilage damage were observed, increasing with time postimplantation. A buildup of lactic acid and/or the rapid loss of scaffold mechanical integrity due to PLLA degradation are probable causes for the joint abnormalities observed in this study. These results are in sharp contrast to those of our previous successful total meniscus replacement studies using polyarylate [p(DTD DD)] fiber-reinforced scaffolds. This suggests that PLLA fiber as produced in this study cannot be used as reinforcement for a meniscus replacement scaffold.
authors.affiliation: 1 Department of Orthopaedic Surgery, Rutgers Biomedical and Health Sciences-Robert Wood Johnson Medical School , New Brunswick, New Jersey.|2 Department of Biomedical Engineering, Rutgers-The State University of New Jersey , Piscataway, New Jersey.
authors.forename: Jay M
authors.initials: JM
authors.lastname: Patel
authors.affiliation: 1 Department of Orthopaedic Surgery, Rutgers Biomedical and Health Sciences-Robert Wood Johnson Medical School , New Brunswick, New Jersey.|2 Department of Biomedical Engineering, Rutgers-The State University of New Jersey , Piscataway, New Jersey.
authors.forename: Aaron R
authors.initials: AR
authors.lastname: Merriam
authors.affiliation: 2 Department of Biomedical Engineering, Rutgers-The State University of New Jersey , Piscataway, New Jersey.|3 New Jersey Center for Biomaterials, Rutgers-The State University of New Jersey , Piscataway, New Jersey.
authors.forename: Joachim
authors.initials: J
authors.lastname: Kohn
authors.affiliation: 1 Department of Orthopaedic Surgery, Rutgers Biomedical and Health Sciences-Robert Wood Johnson Medical School , New Brunswick, New Jersey.|2 Department of Biomedical Engineering, Rutgers-The State University of New Jersey , Piscataway, New Jersey.
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Gatt
authors.affiliation: 1 Department of Orthopaedic Surgery, Rutgers Biomedical and Health Sciences-Robert Wood Johnson Medical School , New Brunswick, New Jersey.|2 Department of Biomedical Engineering, Rutgers-The State University of New Jersey , Piscataway, New Jersey.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Dunn
mesh_terms: D000818:Animals; D019645:Arthroplasty, Replacement, Knee; D000072600:Meniscus; D011091:Polyesters / Q000009:adverse effects* / Q000737:chemistry; D011475:Prosthesis Failure; D012756:Sheep; D013997:Time Factors; D054457:Tissue Scaffolds / Q000009:adverse effects* / Q000737:chemistry
chemical_list: D011091:Polyesters; C033616:poly(lactide)