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Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_6 | Pages 25 - 25
1 May 2019
Langton D Sidaginamale R Wells S Wainwright B Holland J Deehan D Joyce T Jafri A Nargol A Natu S
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Introduction

We aimed to identify genes associated with the development of ALVAL at relatively low levels of wear.

Methods

At our unit all patients undergoing revision of a MoM hip prosthesis have periprosthetic tissue samples graded for ALVAL. Explants undergo volumetric wear testing of the bearing and taper surfaces. We identified patients with moderate/severe ALVAL who had been exposed to lower than the median wear rate of all recorded patients who had developed ALVAL (<3mm3/year). This was termed the “ALVAL” group. We then identified all patients whose tissues had shown no signs of ALVAL. The patients in the two groups were sent buccal DNA collection kits. DNA was examined using next generation sequencing. Alleleic frequencies in the two groups were compared using Fisher's test and compared to a background UK population group (n=8514). We then conducted binary logistic regression with patient age, sex, primary source of debris (taper/bearing) and HLA genotype as the predictors. With the hypothesis that a cobalt/albumin metalloprotein acts as the epitope, we used validated binding prediction software to determine the relative affinities of the binding grooves created by different DQA1/DQB1 genetic combinations for albumin derived peptides. Given the protection that male sex and younger age appears to confer against ALVAL, we hypothesized that testosterone peptides may compete for these binding sites.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_11 | Pages 7 - 7
1 Jun 2016
Sidaginamale R O'Hare J Natu S Joyce T Lord J Nargol A Langton D
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Background

Some reports have suggested that debris generated from the head neck taper junction is more destructive than equivalent doses from metal bearing surfaces.

Methods

Part 1. We examined the relationship between the source (taper/bearing) and volume of metal debris on Cr and Co concentrations in corresponding blood and hip synovial fluid samples and the observed agglomerated particle sizes in excised tissues using regression analysis of prospectively collected data at a single revision unit. Part 2. We investigated variables most strongly associated with macroscopic soft tissue injury as documented at revision surgery using ordinal logistic regression. Independent variables included source and volume of CoCr exposure, Cr and Co joint fluid concentrations, joint fluid grade, ALVAL (Aseptic Lymphocytic Vasculitis Associated Lesion) grade, presence of vascular hyalinisation, agglomerated particle size, implant type, patient sex and age.


Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_12 | Pages 5 - 5
1 Nov 2015
Langton D Killen M Sidaginamale R Bowsher J Savisaar C Nargol A Joyce T Lord J
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Introduction

In this study, we aimed to investigate the effect of the topography of the female taper surface on taper wear.

Patients/Materials & Methods

We measured volumetric material loss at the female taper surface of the first consecutive 36mm MoM hips received at our centre. The MoM hips were from a single manufacturer and possessed matching: head size (36mm); taper geometry (5.65 degree 12 14 tapers); and metallurgy (cobalt chrome female taper mated with a titanium stem). Volume loss was measured with a coordinate measuring machine using validated methods. Surface roughness was measured using a Surftest SJ400. There were 111 head tapers available for analysis. The majority had been revised secondary to ARMD, and a minority for loosening. The mean duration of implantation was 56 months. Volumetric wear values were log normalised in order to construct a multiple regression model to investigate the interaction of head offset, the head taper angle and the Rp value of the female taper surface. Rp is a roughness parameter, which is a measure of the peaks above the plateau of a surface.


Bone & Joint Research
Vol. 1, Issue 4 | Pages 56 - 63
1 Apr 2012
Langton DJ Sidaginamale R Lord JK Nargol AVF Joyce TJ

Objectives

An ongoing prospective study to investigate failing metal-on-metal hip prostheses was commenced at our centre in 2008. We report on the results of the analysis of the first consecutive 126 failed mated total hip prostheses from a single manufacturer.

Methods

Analysis was carried out using highly accurate coordinate measuring to calculate volumetric and linear rates of the articular bearing surfaces and also the surfaces of the taper junctions. The relationship between taper wear rates and a number of variables, including bearing diameter and orientation of the acetabular component, was investigated.


The Journal of Bone & Joint Surgery British Volume
Vol. 93-B, Issue 8 | Pages 1011 - 1016
1 Aug 2011
Langton DJ Jameson SS Joyce TJ Gandhi JN Sidaginamale R Mereddy P Lord J Nargol AVF

There is widespread concern regarding the incidence of adverse soft-tissue reactions after metal-on-metal (MoM) hip replacement. Recent National Joint Registry data have shown clear differences in the rates of failure of different designs of hip resurfacing. Our aim was to update the failure rates related to metal debris for the Articular Surface Replacement (ASR). A total of 505 of these were implanted.

Kaplan-Meier analysis showed a failure rate of 25% at six years for the ASR resurfacing and of 48.8% for the ASR total hip replacement (THR). Of 257 patients with a minimum follow-up of two years, 67 (26.1%) had a serum cobalt concentration which was greater than 7 μg/l. Co-ordinate measuring machine analysis of revised components showed that all patients suffering adverse tissue reactions in the resurfacing group had abnormal wear of the bearing surfaces. Six THR patients had relatively low rates of articular wear, but were found to have considerable damage at the trunion-taper interface. Our results suggest that wear at the modular junction is an important factor in the development of adverse tissue reactions after implantation of a large-diameter MoM THR.