title: Evaluating the Surface Topography of Pyrolytic Carbon Finger Prostheses through Measurement of Various Roughness Parameters.
abstract: The articulating surfaces of four different sizes of unused pyrolytic carbon proximal interphalangeal prostheses (PIP) were evaluated though measuring several topographical parameters using a white light interferometer: average roughness (Sa); root mean-square roughness (Sq); skewness (Ssk); and kurtosis (Sku). The radii of the articulating surfaces were measured using a coordinate measuring machine, and were found to be: 2.5, 3.3, 4.2 and 4.7 mm for proximal, and 4.0, 5.1, 5.6 and 6.3 mm for medial components. ANOVA was used to assess the relationship between the component radii and each roughness parameter. Sa, Sq and Ssk correlated negatively with radius (p = 0.001, 0.001, 0.023), whilst Sku correlated positively with radius (p = 0.03). Ergo, the surfaces with the largest radii possessed the better topographical characteristics: low roughness, negative skewness, high kurtosis. Conversely, the surfaces with the smallest radii had poorer topographical characteristics.
authors.affiliation: School of Mechanical and Systems Engineering, Newcastle University, Newcastle upon Tyne, England NE1 7RU, UK. andrew.naylor@newcastle.ac.uk.
authors.forename: Andrew
authors.initials: A
authors.lastname: Naylor
authors.affiliation: Upper Limb Research Unit, Wrightington Hospital, Wigan, England WN6 9EP, UK. sctalwalkar@gmail.com.
authors.forename: Sumedh C
authors.initials: SC
authors.lastname: Talwalkar
authors.affiliation: Upper Limb Research Unit, Wrightington Hospital, Wigan, England WN6 9EP, UK. ian.trail@wwl.nhs.uk.
authors.forename: Ian A
authors.initials: IA
authors.lastname: Trail
authors.affiliation: School of Mechanical and Systems Engineering, Newcastle University, Newcastle upon Tyne, England NE1 7RU, UK. thomas.joyce@newcastle.ac.uk.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Joyce
keywords: kurtosis; proximal interphalangeal joint; pyrolytic carbon; roughness parameters; skewness; surface topography