Condition category
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Mr John Timperley


Contact details

Royal Devon & Exeter Hospital (Wonford)
Barrack Road
United Kingdom
+44 (0)1392 403544

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Optimum socket fixation at total hip replacement


Study hypothesis

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

Not provided at time of registration

Study design

Randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet


Surgery: Total hip replacement


A controlled, prospective trial to compare forms of socket fixation.

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



Not Specified

Drug names

Primary outcome measures

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 trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

Any patient under 80 years of age undergoing primary total hip replacement at the Princess Elizabeth Orthopaedic Centre (PEOC) are eligible.

Participant type


Age group




Target number of participants

Not applicable

Participant exclusion criteria

Patients refusing informed consent to the trial.

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Royal Devon & Exeter Hospital (Wonford)
Exeter, Devon
United Kingdom

Sponsor information


Department of Health (UK)

Sponsor details

Richmond House
79 Whitehall
United Kingdom

Sponsor type




Funder type


Funder name

Royal Devon and Exeter NHS Trust (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes