Medical Device Alert: Metal-on-metal (MoM) total hip replacements (MDA/2012/016)

If you are in England, please send enquiries about this notice to the MHRA, quoting reference number MDA/2012/016 or 2011/009/006/291/004.

Technical aspects
Mr John McManus or Dr Crina Cacou
Medicines & Healthcare products Regulatory Agency
Floor 4
151 Buckingham Palace Road
London SW1W 9SZ
Tel: 020 3080 7226 or 020 3080 7338
Fax: 020 8754 3965
Email: john.mcmanus@mhra.gsi.gov.uk or crina.cacou@mhra.gsi.gov.uk

Clinical aspects
Dr Nicola Lennard
Medicines & Healthcare products Regulatory Agency
Floor 4
151 Buckingham Palace Road
London SW1W 9SZ
Tel: 020 3080 7126
Fax: 020 8754 3965
Email: nicola.lennard@mhra.gsi.gov.uk

How to report adverse incidents

Please report via our website: Reporting adverse incidents involving medical devices 
Further information about CAS can be found on the CAS website (external link)

Alerts in Northern Ireland will continue to be distributed via the NI SABS system.

Enquiries and adverse incident reports in Northern Ireland should be addressed to:

Northern Ireland Adverse Incident Centre
Health Estates Investment Group
Room 17
Annex 6
Castle Buildings
Stormont Estate
Dundonald BT4 3SQ

Tel:    02890 523 704
Fax:   02890 523 900
Email:    NIAIC@dhsspsni.gov.uk

How to report adverse incidents in Northern Ireland

Please report directly to NIAIC, further information can be found on the NIAIC website (external link)
Further information about SABS can be found on the SABS website (external link)

Enquiries and adverse incident reports in Scotland should be addressed to:

Incident Reporting and Investigation Centre
Health Facilities Scotland
NHS National Services Scotland
Gyle Square
1 South Gyle Crescent
Edinburgh EH12 9EB

Tel: 0131 275 7575
Fax: 0131 314 0722

Email: nss.iric@nhs.net

Health Facilities Scotland Incident Reporting and Investigation Centre (IRIC) (external link)

Enquiries in Wales should be addressed to:

Dr Chris Jones
Medical Director
Medical Device Alerts
Welsh Assembly Government
Cathays Park
Cardiff CF10 3NQ

Tel: 029 2082 3922
Email: Haz-Aic@wales.gsi.gov.uk

Increased rates of revision of metal-on-metal total hip replacements when MITCH TRH acetabular cups/MITCH TRH modular heads are used in combination with uncemented Accolade femoral stems.

The MITCH TRH System is a metal-on-metal hip replacement system consisting of components that can be used in different combinations to carry out either hip resurfacing arthroplasty or total hip replacement. The system was manufactured by Finsbury Orthopaedics and was distributed in the UK by Stryker Orthopaedics between May 2006 and October 2011.*

Analysis of data from the England and Wales National Joint Registry (NJR) up to 10 March 2012 has shown that the cumulative revision rate for MITCH TRH System used in hip resurfacing arthroplasty (revision rate of 3.1 % at 4 years based on 769 patients recorded by the NJR) is in line with relevant guidance from the National Institute for Health and Clinical Excellence (NICE) guidance,^1,2 but that the cumulative revision rate for MITCH TRH System total hip replacements (revision rate of 8.8% at 4 years based on 445 patients recorded by the NJR) is higher than indicated as acceptable by NICE.

MITCH TRH total hip replacements consist of MITCH TRH acetabular cups used with MITCH TRH modular femoral heads and also an appropriate Stryker femoral stem with a V40 taper including Exeter V40 or uncemented Accolade or ABG II.

Further analysis of NJR data by DePuy has now determined that the cumulative revision rate of MITCH TRH System total hip replacements varies considerably depending upon which femoral stem is used:

• MITCH TRH with Exeter V40 – revision rate of 3.7% at 4 years based on 120 patients recorded by the NJR
• MITCH TRH with uncemented Accolade – revision rate of 10.7% at 4 years based on 271 patients
  recorded by the NJR
• MITCH TRH with ABG II - rate of usage too low to estimate revision rate.

*Note: DePuy International acquired Finsbury Orthopaedics in 2009 and they are now responsible for the safety and monitoring of the MITCH TRH hip system.

References:

1. Guidance on the selection of prostheses for primary total hip replacement. National Institute for Health and Clinical Excellence (NICE), 2000. Technology appraisal guidance No. 2
2. Guidance on the use of metal on metal hip resurfacing arthroplasty. National Institute for Health and Clinical Excellence (NICE), 2002. Technology Appraisal Guidance No. 44.

• Do not implant MITCH TRH acetabular cups/MITCH TRH modular heads in combination with uncemented Accolade femoral stems.
• Follow up both symptomatic and asymptomatic patients implanted with this combination as detailed in Table 1.
• Report all adverse incidents to the MHRA, DePuy International and Stryker Orthopaedics.

Table 1 - Management recommendations for patients with stemmed MoM total hip replacements – femoral head diameter ≥36mm (originally published in the MHRA’s MDA/2012/008)

Table 1 footnotes:

• Blood metal ion testing to be in whole blood.
• 7 parts per billion (ppb) equals 119 nmol/L cobalt or 134.5 nmol/L chromium.

Measurements of cobalt or chromium ions should be carried out:

• in England, Northern Ireland or Wales, by laboratories participating in the Trace ElementsExternal Quality Assessment Scheme (TEQAS) (external link)
• in Scotland, by the Scottish Trace Element and Micronutrient Reference Laboratories Scottish Trace Element and Micronutrient Reference Laboratory (external link)

Guidance notes:

• On the basis of current knowledge, this chart has been produced as a guide to the management of these patients. It will not necessarily cover all clinical situations and each patient must be judged individually.
• MARS MRI scans (or ultrasound scans) should carry more weight in decision making than blood ion levels alone.
• Patients with muscle or bone damage on MARS MRI are those of most concern. A fluid collection alone around the joint in an asymptomatic patient, unless it is very large can be safely observed with interval scanning.
• Local symptoms include pain and limping.

Action by

• Medical directors
• Orthopaedic departments
• Orthopaedic surgeons
• Staff involved in the management of patients with joint replacement implant

This MDA has been sent to:

• NHS trusts in England (chief executives)
• Care Quality Commission (CQC) (headquarters) for information
• HSC trusts in Northern Ireland (chief executives)
• NHS boards in Scotland (equipment coordinators)
• NHS boards and trusts in Wales (chief executives)
• Primary care trusts in England (chief executives)

Onward distribution

Please bring this notice to the attention of relevant employees in your establishment. Below is a suggested list of recipients.

Trusts
CAS and SABS (NI) liaison officers for onward distribution to all relevant staff including:

• Clinical governance leads
• Medical directors
• Nursing executive directors
• Orthopaedic departments
• Orthopaedic outpatient clinics
• Orthopaedic surgeons
• Outpatient theatre managers
• Pathologists
• Radiology departments
• Radiology directors
• Risk managers
• Theatre managers

Primary care trusts

• CAS liaison officers for onward distribution to all relevant staff including:
• Directors of public health
• General practitioners (for information only)
• NHS walk-in centres

Independent distribution

Establishments registered with the Care Quality Commission (CQC) (England only)
This alert should be read by:

• Hospitals in the independent sector
• Independent treatment centres
• Private medical practitioners

Please note: CQC and OFSTED do not distribute these alerts. Independent healthcare providers and social care providers can sign up to receive MDAs directly from the Department of Health’s Central Alerting System (CAS) by sending an email to: safetyalerts@dh.gsi.gov.uk and requesting this facility.

DePuy International Ltd
Paul Arnott
Complaints & Vigilance Manager
Tel: 07771 971 930
Email: parnott@its.jnj.com

Stryker Orthopaedics, Inc.
Nick Margree
Director, Global Brand Marketing (Stryker UK)
Tel: 01635 262 400
Email: nick.margree@stryker.com