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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
Full Access

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. 98-B, Issue SUPP_11 | Pages 4 - 4
1 Jun 2016
O'Hare J Langton D Nargol A Joyce T Brewster N Cooke N Jafri A Lord J Duffy P Holland J
Full Access

Introduction

Historical studies have reported incidences of taper corrosion in retrieved MoP hips of 20–50%. These studies relied on visual assessments, rather than using modern analytical techniques.

Patients/Materials and Methods

The Northern Retrieval Registry was initiated to routinely analyse all retrieved hips. The volumetric wear rates of retrieved Exeter head tapers were measured using a coordinate measuring machine using validated methods and compared to the available results obtained from an ongoing study of failed MoM prostheses. Power analysis suggested that we would need at least fifty Exeter head tapers to provide significant results. Non-parametric tests were used to assess differences. We have previously identified head diameter/offset/taper angle and taper surface roughness as variables associated with taper wear. The effect of bearing material combination remains unquantified. These design variables were entered into a multiple regression model following log normalisation of taper wear.


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
Full Access

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.


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.


The Journal of Bone & Joint Surgery British Volume
Vol. 93-B, Issue 2 | Pages 164 - 171
1 Feb 2011
Langton DJ Joyce TJ Jameson SS Lord J Van Orsouw M Holland JP Nargol AVF De Smet KA

We sought to establish the incidence of joint failure secondary to adverse reaction to metal debris (ARMD) following metal-on-metal hip resurfacing in a large, three surgeon, multicentre study involving 4226 hips with a follow-up of 10 to 142 months. Three implants were studied: the Articular Surface Replacement; the Birmingham Hip Resurfacing; and the Conserve Plus. Retrieved implants underwent analysis using a co-ordinate measuring machine to determine volumetric wear. There were 58 failures associated with ARMD. The median chromium and cobalt concentrations in the failed group were significantly higher than in the control group (p < 0.001). Survival analysis showed a failure rate in the patients with Articular Surface Replacement of 9.8% at five years, compared with < 1% at five years for the Conserve Plus and 1.5% at ten years for the Birmingham Hip Resurfacing. Two ARMD patients had relatively low wear of the retrieved components. Increased wear from the metal-on-metal bearing surface was associated with an increased rate of failure secondary to ARMD. However, the extent of tissue destruction at revision surgery did not appear to be dose-related to the volumetric wear.