Influence of implant design on blood metal ion concentrations in metal-on-metal total hip replacement patients

Purpose: Most factors considered to affect blood metal ions following metal-on-metal hip replacement are based on hip resurfacing patients. The study aims were to determine which factors affect blood metal ion concentrations following metal-on-metal total hip replacement (MoM THR). Methods: All unil...

Full description

Bibliographic Details
Main Authors: Matharu, G, Berryman, F, Brash, L, Pynsent, P, Treacy, R, Dunlop, D
Format: Journal article
Published: Springer Berlin Heidelberg 2015
_version_ 1826280760620875776
author Matharu, G
Berryman, F
Brash, L
Pynsent, P
Treacy, R
Dunlop, D
author_facet Matharu, G
Berryman, F
Brash, L
Pynsent, P
Treacy, R
Dunlop, D
author_sort Matharu, G
collection OXFORD
description Purpose: Most factors considered to affect blood metal ions following metal-on-metal hip replacement are based on hip resurfacing patients. The study aims were to determine which factors affect blood metal ion concentrations following metal-on-metal total hip replacement (MoM THR). Methods: All unilateral MoM THR patients at one centre with whole-blood cobalt (Co) and chromium (Cr) concentrations measured up to May 2013 were included. Blood sampling was at a mean of 4.5 years (range 1.1–11.8 years) postoperatively. Results: Of 496 patients (mean age 59.1 years; 52.8 % male), blood metal ions &gt;7 μg/l were observed in 9.7 % (n = 48). Large femoral head sizes (≥38 mm) had significantly higher (p &lt; 0.0001) blood metal ions than smaller sizes (28/36 mm). Corail–Pinnacle implants produced significantly lower blood metal ions compared to other implant designs (p &lt; 0.01 Co and Cr). Univariate linear regression demonstrated the only significant predictors of both blood Co and Cr concentrations were femoral head size (R<sup>2</sup> = 8.6 % Co and R<sup>2</sup> = 3.3 % Cr, both p &lt; 0.0001) and implant design (R<sup>2</sup> = 8.8 %, p = 0.005 Co and R<sup>2</sup> = 5.1 %, p = 0.003 Cr). When the three THR implant design groups (Corail–Pinnacle, Synergy, Other) were analysed separately, femoral head size no longer significantly affected blood metal ions in any of the three implant design groups. Conclusions: Implant design was the most important factor affecting blood metal ion concentrations. We recommend the regularity of follow-up be tailored to survival rates of various MoM THR designs rather than according to femoral head size.
first_indexed 2024-03-07T00:18:33Z
format Journal article
id oxford-uuid:7bb595ff-1b96-4b2b-8e3b-58b9c21c63bf
institution University of Oxford
last_indexed 2024-03-07T00:18:33Z
publishDate 2015
publisher Springer Berlin Heidelberg
record_format dspace
spelling oxford-uuid:7bb595ff-1b96-4b2b-8e3b-58b9c21c63bf2022-03-26T20:52:26ZInfluence of implant design on blood metal ion concentrations in metal-on-metal total hip replacement patientsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:7bb595ff-1b96-4b2b-8e3b-58b9c21c63bfSymplectic Elements at OxfordSpringer Berlin Heidelberg2015Matharu, GBerryman, FBrash, LPynsent, PTreacy, RDunlop, DPurpose: Most factors considered to affect blood metal ions following metal-on-metal hip replacement are based on hip resurfacing patients. The study aims were to determine which factors affect blood metal ion concentrations following metal-on-metal total hip replacement (MoM THR). Methods: All unilateral MoM THR patients at one centre with whole-blood cobalt (Co) and chromium (Cr) concentrations measured up to May 2013 were included. Blood sampling was at a mean of 4.5 years (range 1.1–11.8 years) postoperatively. Results: Of 496 patients (mean age 59.1 years; 52.8 % male), blood metal ions &gt;7 μg/l were observed in 9.7 % (n = 48). Large femoral head sizes (≥38 mm) had significantly higher (p &lt; 0.0001) blood metal ions than smaller sizes (28/36 mm). Corail–Pinnacle implants produced significantly lower blood metal ions compared to other implant designs (p &lt; 0.01 Co and Cr). Univariate linear regression demonstrated the only significant predictors of both blood Co and Cr concentrations were femoral head size (R<sup>2</sup> = 8.6 % Co and R<sup>2</sup> = 3.3 % Cr, both p &lt; 0.0001) and implant design (R<sup>2</sup> = 8.8 %, p = 0.005 Co and R<sup>2</sup> = 5.1 %, p = 0.003 Cr). When the three THR implant design groups (Corail–Pinnacle, Synergy, Other) were analysed separately, femoral head size no longer significantly affected blood metal ions in any of the three implant design groups. Conclusions: Implant design was the most important factor affecting blood metal ion concentrations. We recommend the regularity of follow-up be tailored to survival rates of various MoM THR designs rather than according to femoral head size.
spellingShingle Matharu, G
Berryman, F
Brash, L
Pynsent, P
Treacy, R
Dunlop, D
Influence of implant design on blood metal ion concentrations in metal-on-metal total hip replacement patients
title Influence of implant design on blood metal ion concentrations in metal-on-metal total hip replacement patients
title_full Influence of implant design on blood metal ion concentrations in metal-on-metal total hip replacement patients
title_fullStr Influence of implant design on blood metal ion concentrations in metal-on-metal total hip replacement patients
title_full_unstemmed Influence of implant design on blood metal ion concentrations in metal-on-metal total hip replacement patients
title_short Influence of implant design on blood metal ion concentrations in metal-on-metal total hip replacement patients
title_sort influence of implant design on blood metal ion concentrations in metal on metal total hip replacement patients
work_keys_str_mv AT matharug influenceofimplantdesignonbloodmetalionconcentrationsinmetalonmetaltotalhipreplacementpatients
AT berrymanf influenceofimplantdesignonbloodmetalionconcentrationsinmetalonmetaltotalhipreplacementpatients
AT brashl influenceofimplantdesignonbloodmetalionconcentrationsinmetalonmetaltotalhipreplacementpatients
AT pynsentp influenceofimplantdesignonbloodmetalionconcentrationsinmetalonmetaltotalhipreplacementpatients
AT treacyr influenceofimplantdesignonbloodmetalionconcentrationsinmetalonmetaltotalhipreplacementpatients
AT dunlopd influenceofimplantdesignonbloodmetalionconcentrationsinmetalonmetaltotalhipreplacementpatients