Metal Ions in Ceramic on Metal Total Hip Arthroplasty

NCT ID: NCT01437124

Last Updated: 2016-06-06

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 83 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2011-10-31
• Study Completion Date: 2012-05-31

Brief Summary

The investigators aim to measure the blood levels of certain metals in a group of patients all of whom have had a ceramic on metal total hip replacement. This new bearing surface (joint) is relatively new and the investigators are currently following up the largest cohort in the world. Clinical results are currently excellent at 2 years in all patients, however the investigators are mindful of the lessons learned from the high failure rate of several designs of metal on metal hip replacements as well as several in vitro reports and one in vivo case report of elevated metal levels in this particular implant. The investigators feel it is important to measure the metal ion levels in our group to ascertain and compare these with reference standards. Once performed the investigators can relate ion levels to function and x ray changes and provide useful longterm data to the patients and the wider medical community as to whether this bearing surface is safe in the long term or whether it's use should be abandoned. This is useful as there are numerous groups implanting this device in the UK and in addition it has just been awarded FDA approval in the USA - its use is likely to flourish.

Detailed Description

PURPOSE & DESIGN:

The investigators are currently following up a cohort of patients all of whom have had a metal on ceramic total hip arthroplasty.

This new bearing couple has been approved for use in the UK for some time and has recently achieved USA FDA approval.

The attraction of this bearing couple is a low rate of wear with reduced complications associated with ceramic on ceramic bearing such as bearing fracture.

Of recent media attention has been the unacceptably high failure of the DePuy ASR metal on metal hip resurfacing. This metal on metal bearing couple has been associated with increased ion levels and chromosome abnormalities in vivo.

In vitro studies and small in vivo studies have revealed much lower wear, particle numbers and ion levels in ceramic on metal studies than in metal on metal bearing surfaces; however there is no large scale evidence that this is the case.

The investigators currently are following up the largest worldwide series of ceramic on metal bearings and clinical results are excellent. It is important however to obtain hard data on metal ion levels in this population firstly to ensure the long term function and health of this cohort but also to provide a barometer for other surgeons who will be using a prosthesis that as yet has little in the way of long term follow up and data on ion levels in a large cohort.

If the ion levels are unacceptably high then the investigators will need to follow these patients closely and offer revision surgery if there are clinical concerns.

For similar reasons it is important to monitor for chromosomal abnormalities.

Conditions

Osteoarthritis; Avascular Necrosis; Rheumatoid Arthritis; Developmental Dysplasia of the Hip

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

Ceramic on metal THA

Those who have received a ceramic on metal total hip replacement

No interventions assigned to this group

Eligibility Criteria

Inclusion Criteria

• Over 18 years of age
• Complete history and physical examination
• Previously performed ceramic on metal total hip replacement
• An understanding of the purpose of the study and signed consent form

Exclusion Criteria

• Hip arthroplasty other than ceramic on metal bearing
• Mentally infirm / incapacitated
• Incomplete history or physical examination
• Unwillingness to participate in the study

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Hussain Kazi

OTHER

Sponsor Role: lead

Responsible Party

Hussain Kazi

Specialist Registrar, Trauma and Orthopaedics

Responsibility Role: SPONSOR_INVESTIGATOR

Principal Investigators

Fintan A Carroll, MBBS, FRCS

Role: STUDY_DIRECTOR

Consultant Orthopaedic Surgeon

Hussain A Kazi, MBChB,FRCS

Role: PRINCIPAL_INVESTIGATOR

Specialist Registrar, Trauma & Orthopaedics

Locations

Wirral University Teaching Hospitals NHS Foundation Trust

Metropolitan Borough of Wirral, Merseyside, United Kingdom

Countries

United Kingdom

Other Identifiers

960558216

Identifier Type: -

Identifier Source: org_study_id