Using small angle X-ray scattering to investigate the variation in composition across a graduated region within an intervertebral disc prosthesis

• Published in: Journal of materials science. Materials in medicine Vol. 21; no. 2; pp. 787 - 795
• Main Authors: Gwynne, J. H., Cameron, R. E.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.02.2010; Springer; Springer Nature B.V
• Subjects: Biocompatible Materials - chemistry; Biological and medical sciences; Biomaterials; Biomedical Engineering and Bioengineering; Biomedical materials; Ceramics; Chemistry and Materials Science; Composites; Equipment Failure Analysis; Glass; Intervertebral Disc - surgery; Materials Science; Materials Testing; Medical sciences; Natural Materials; Orthopedic surgery; Polymer Sciences; Polyurethanes - chemistry; Prostheses; Prostheses and Implants; Prosthesis Design; Prototypes; Regenerative Medicine/Tissue Engineering; Scattering, Small Angle; Spine; Surfaces and Interfaces; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Technology. Biomaterials. Equipments; Thin Films; X-Ray Diffraction; X-rays; HMDI; Polyurethane; Hard Segment; Soft Segment; Polycarbonate Urethane; Osteoarticular system; Lumbar spine; Prosthesis; Exploration; Biomaterial; Small angle X ray scattering; Intervertebral disk; Biomedical engineering
• ISSN: 0957-4530; 1573-4838
• DOI: 10.1007/s10856-009-3869-z

The CAdisc-L is a polycarbonate urethane lumbar intervertebral disc prosthesis that aims to replicate the mechanical properties of a natural disc as closely as possible. In this work, Small Angle X-ray Scattering (SAXS) was used to investigate the variation in composition across prototype disc samples containing annulus and nucleus regions separated by a graduated region. An empirical data analysis method was developed involving the calculation of intensity ratios, since the SAXS data did not readily fit any of the standard analysis models. Calibration samples were used to quantify the variation in SAXS response with composition and a linescan method was employed to ascertain the change in composition across discs manufactured with different graduated region volumes. The graduated region width increases with the volume incorporated into it during manufacture, as expected, but the properties do not vary linearly across the graduated regions. The method developed during this work can be adapted for use with any series of polymer samples that shows a systematic variation in SAXS behaviour with composition.