Premium
Variation in taper surface roughness for a single design effects the wear rate in total hip arthroplasty
Author(s) -
Whittaker Robert K.,
Hothi Harry S.,
Eskelinen Antti,
Blunn Gordon W.,
Skinner John A.,
Hart Alister J.
Publication year - 2017
Publication title -
journal of orthopaedic research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.041
H-Index - 155
eISSN - 1554-527X
pISSN - 0736-0266
DOI - 10.1002/jor.23456
Subject(s) - surface roughness , materials science , surface finish , composite material
Material loss from the head‐stem taper junction of total hip arthroplasty (THA) is implicated in adverse reactions to metal debris (ARMD); the mechanisms for this are multi‐factorial. We investigated the relationship between the roughness of the “as manufactured” taper surface and the wear rate from this junction. Fifty retrieved Pinnacle metal‐on‐metal (MOM) bearings paired with a Corail stem were included in the study. Multivariable statistical analysis was performed to determine the influence of taper roughness on material loss rate after controlling for other confounding surgical, implant, and patient factors. The surface roughness of the “as manufactured” head taper surface was associated with the rate of material loss from this surface. Four of eighteen roughness variables taken from ISO 4,287 and ISO 13,565‐2 were significant: The Reduced Peak Height (Rpk, the protruding peaks above the core) ( p = 0.004), Material Ratio 1 (Mr1, the ratio of the protruding peaks above the core) ( p = 0.002), Area of the Peak Region (A1, the area of the Abbott‐Curve that contains the peaks from the profile) ( p = 0.003) and the Skewness (Rsk, the asymmetry of the height distribution corresponding to the height or depth of surface features) ( p = 0.03). We found a large variability in the measured values with a median (range) of 0.50 (0.05–2.98), 11.98 (0.46–39.98), 30.89 (0.15–581.00), and 0.04 (−0.73–0.84), respectively. A 1‐unit increase in Rpk was associated with a 73% increase in the taper wear rate. The variability of “as manufactured” surface roughness has a significant effect on taper material loss. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1784–1792, 2017.