title: Radiopaque UHMWPE sublaminar cables for spinal deformity correction: Preclinical mechanical and radiopacifier leaching assessment.
abstract: Polymeric sublaminar cables have a number of advantages over metal cables in the field of spinal deformity surgery, with decreased risk of neurological injury and potential for higher correction forces as the two most predominant. However, currently available polymer cables are radiolucent, precluding postoperative radiological assessment of instrumentation stability and integrity. This study provides a preclinical assessment of a woven UHMWPE cable made with radiopaque UHMWPE fibers. Our primary goal was to determine if the addition of a radiopacifier negatively affects the mechanical properties of UHMWPE woven cables. Tensile mechanical properties were determined and compared to suitable controls. Radiopacity was evaluated and radiopacifier leaching was assessed in vitro and in vivo. Finally, in vivo bismuth organ content was quantified after a 24-week implantation period in sheep. Results show that the mechanical properties of woven UHMWPE cables were not deleteriously affected by the addition of homogenously dispersed bismuth oxide particles within each fiber. Limited amounts of bismuth oxide were released in vitro, well below the toxicological threshold. Tissue concentrations lower than generally accepted therapeutic dosages for use against gastrointestinal disorders, well below toxic levels, were discovered in vivo. These results substantiate controlled clinical introduction of these radiopaque UHMWPE cables. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 771-779, 2018.
authors.affiliation: Department of Orthopaedic Surgery, Research School CAPHRI, Maastricht University Medical Center, Maastricht, the Netherlands.
authors.forename: Alex K
authors.identifier: 0000-0003-4121-8519
authors.initials: AK
authors.lastname: Roth
authors.affiliation: DSM Biomedical BV, Geleen, the Netherlands.
authors.forename: Karlien
authors.initials: K
authors.lastname: Boon-Ceelen
authors.affiliation: DSM Biomedical BV, Geleen, the Netherlands.
authors.forename: Harold
authors.initials: H
authors.lastname: Smelt
authors.affiliation: Orthopaedic Biomechanics, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands.
authors.forename: Bert
authors.initials: B
authors.lastname: van Rietbergen
authors.affiliation: Department of Orthopaedic Surgery, Research School CAPHRI, Maastricht University Medical Center, Maastricht, the Netherlands.
authors.forename: Paul C
authors.initials: PC
authors.lastname: Willems
authors.affiliation: Department of Orthopaedic Surgery, Research School CAPHRI, Maastricht University Medical Center, Maastricht, the Netherlands.
authors.forename: Lodewijk W
authors.initials: LW
authors.lastname: van Rhijn
authors.affiliation: Department of Orthopaedic Surgery, Research School CAPHRI, Maastricht University Medical Center, Maastricht, the Netherlands.
authors.forename: Jacobus J
authors.initials: JJ
authors.lastname: Arts
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000737:chemistry / Q000494:pharmacology; D016268:Internal Fixators; D008422:Materials Testing; D011095:Polyethylenes / Q000737:chemistry / Q000494:pharmacology; D012756:Sheep; D013131:Spine / Q000002:abnormalities* / Q000601:surgery*
chemical_list: D003287:Contrast Media; D011095:Polyethylenes; C111601:ultra-high molecular weight polyethylene
keywords: UHMWPE fibers; bismuth oxide; radiopaque; spinal deformity; sublaminar cables