Optimum socket fixation at total hip replacement

ISRCTN	ISRCTN58077053
DOI	https://doi.org/10.1186/ISRCTN58077053
Secondary identifying numbers	N0203096528

Submission date: 12/09/2003
Registration date: 12/09/2003
Last edited: 16/04/2015

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Surgery

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English summary of protocol

Not provided at time of registration

Contact information

Mr John Timperley
Scientific

Royal Devon & Exeter Hospital (Wonford)
Barrack Road
Exeter
EX2 5BW
United Kingdom

Phone	+44 (0)1392 403544
Email	abc@email.com

Study information

Study design	Randomised controlled trial
Primary study design	Interventional
Secondary study design	Randomised controlled trial
Study setting(s)	Hospital
Study type	Treatment
Scientific title	Optimum socket fixation at total hip replacement
Study objectives	For patients 65 and under the aim of this project is to show whether the use of cemented or uncemented sockets at total hip replacement confers the best clinical and radiological results. For older patients the aim is to establish which of two techniques of cementing the socket confers the best results. Patients will be divided into two groups on the basis of their age. Patients under the age of 65 will be randomised into a cemented or cementless group for socket fixation. Patients over 65 will have cemented sockets inserted using two long established techniques of cementing i.e. with or without a flange attached to the socket. Patients entering into the study will have tantulum markers inserted into the pelvis and prosthetic socket at the time of their hip replacement. The subsequent radiological follow-up will be carried out using the technique of Radiostereometry (RSA). The study should show if there is any advantage in using expensive uncemented sockets in younger patients; the cemented arm of the trial should define whether the use of a flanged socket confers any advantage to a patient who has a cemented socket inserted. Roentgen Stereophotogrammetric Analysis (RSA) will detect early micromotion of the implants and will allow comparison of wear rates at the articulation. It may be possible to see at an early stage what sort of socket fixation is optimum.
Ethics approval(s)	Not provided at time of registration
Health condition(s) or problem(s) studied	Surgery: Total hip replacement
Intervention	A controlled, prospective trial to compare forms of socket fixation. Randomisation: Randomisation by sealed envelope in theatre into groups depending on age at surgery: A. Patients 65 and under: 1. To have a cementless socket 2. To have a cemented socket B. Patients aged 65 - 80: 1. To have cemented socket with flange attached to rim for pressurisation 2. To have identical cemented socket without flange attached to rim Techniques and protocols: All other surgical techniques and protocols will be identical between the groups and follow existing practice. All of the implants to be used are currently stocked at PEOC under existing NHS contracts. All surgical techniques to be used are universally accepted as contemporary practice. Tantalum markers (0.8 mm or 1.0 mm) will be inserted into the rim of the socket and into the pelvic bone around the implant. Subsequent radiographs will be taken using a stereoradiographic method known as radiostereometric analysis (RSA) developed in 1974 by Goran Seivik. This method allows very accurate 3-dimensional measurements to be made from radiographs. The tantalum balls have been inserted in at least 6000 patients over the past 30 years and no serious adverse reaction has ever been documented during or after insertion of the markers (Karrholm et al 1997). The radiation dose from a radiographic examination is usually lower than the corresponding conventional one. In studies of the hip, radiation doses of 0.2-0.3 mSv have been calculated by Prof Karrhoim's group (10-20% of a conventional examination including anteroposterior (AP), lateral and pelvis view). The technique involves the use of higher kilovoltages and lower current from the X-ray generator thus reducing the dose of radiation to the patient. Patients who have their operation on the Hip Unit at the Princess Elizabeth Orthopaedic Centre in Exeter are routinely X-rayed post-operatively and then reviewed at six weeks, six months and then at approximately three yearly intervals thereafter indefinitely. The group enrolled for this study will have additional reviews with X-rays at one year and two years. The films taken at each clinic attendance will be in place of the conventional series.
Intervention type	Procedure/Surgery
Primary outcome measure	1. Life tables and Survival Curves with confidence limits for different definitions of failure including implant loosening and radiological evidence of failure including implant migration (as defined by RSA), excessive wear, radiolucencies etc. 2. Log rank comparison.
Secondary outcome measures	Not provided at time of registration
Overall study start date	30/11/1999
Completion date	30/11/2004

Eligibility

Participant type(s)	Patient
Age group	Adult
Sex	Both
Target number of participants	Not applicable
Key inclusion criteria	Any patient under 80 years of age undergoing primary total hip replacement at the Princess Elizabeth Orthopaedic Centre (PEOC) are eligible.
Key exclusion criteria	Patients refusing informed consent to the trial.
Date of first enrolment	30/11/1999
Date of final enrolment	30/11/2004

Locations

Countries of recruitment

England
United Kingdom

Study participating centre

Royal Devon & Exeter Hospital (Wonford)

Exeter, Devon
EX2 5BW
United Kingdom

Sponsor information

Department of Health (UK)
Government

Richmond House
79 Whitehall
London
SW1A 2NL
United Kingdom

Website	http://www.doh.gov.uk

Funders

Funder type

Government

Royal Devon and Exeter NHS Trust (UK)

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not provided at time of registration
Publication and dissemination plan	Not provided at time of registration
IPD sharing plan