Condition category
Musculoskeletal Diseases
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

Miss Katie Roebuck


Contact details

Keele University
Medical Research Unit
Thornburrow Drive
Stoke on Trent
United Kingdom

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title


Study hypothesis

The Low Contact Stress (LCS) rotating platform Total Knee Arthroplasty (TKA) system attempts as near-normal reproduction of knee motion as possible, minimising interface stresses by allowing rotation (with this design, the posterior cruciate ligament has to be sacrificed). The AnteroPosterior (AP) glide LCS type allows both AP glide and rotation (with this design, the posterior cruciate ligament needs to be intact to allow normal femoral rollback). Rather than imposing a predetermined pattern of motion, the AP glide design permits bearing movement, which corresponds to the requirements of individual patient anatomy.

We hypothesise that these features of the AP glide type may allow improved joint position sense (proprioception) and better overall functional outcome. The LCS rotating platform design has good clinical results, but as results improve in terms of flexion and long term survival, more subtle measures of the return to near normal postoperative function become important. Proprioceptive function is affected by osteoarthritic process in knee joint. As it is one of the protective mechanisms, one should aim to preserve or enhance proprioception. Proprioceptive function after TKA is debated and there are conflicting results from various studies. Postoperative improvement depends on a number of factors including implant design and patient associated factors. To our knowledge there is no published study (literature search in Medline and National Research Register), which compares the results of AP glide and rotating platform design LCS knee arthroplasty. Therefore, we feel that a study in this subject is required.

We have conducted a pilot study (randomised controlled trial) to compare these two designs. 30 patients were randomly allocated either AP glide or rotating platform group. On the basis of data from the pilot study we have calculated that we need 44 patients (22 in each group) for the study. We have not made any changes at all in the methodology of the pilot study. After discussing with the team members involved in this study, it seems reasonable to include the patients from the pilot study. Hence we think that we need to recruit 20 more patients to complete the study.

Ethics approval

North Staffordshire Local Research Ethics Committee - Favourable opinion received 19th October 2004.

Study design

A randomised controlled trial comparing the effects of AP glide and rotating platform design LCS knee arthroplasty.

Primary study design


Secondary study design

Randomised controlled trial

Trial setting

Not specified

Trial type


Patient information sheet




1. Study and compare the improvement in knee motion and overall function after AP glide and rotating platform design LCS knee arthroplasty.
2. Examine the effect of this intervention on proprioception.

Intervention type



Not Specified

Drug names

Primary outcome measures

The primary outcome measure for this study will be the improvement in knee motion (as measured by FASTRAK system). This will be done before operation and at three and six months after the operation at bionic laboratory at Hartshill Orthopaedic Surgical Unit.

Secondary outcome measures

1. Proprioception as measured by absolute error angle (this is the difference between actual and perceived angle through which the joint has been moved passively).
2. American knee society score, oxford knee score, EuroQol instrument and the Short Form health survey (SF12) will be recorded before and at three months after the operation.
3. Complications
4. Statistical considerations

Overall trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

1. Patients require a primary bi- or tri- compartmental knee replacement
2. Patients require unilateral knee replacement
3. Patients have given their voluntary, written informed consent

Participant type


Age group

Not Specified


Not Specified

Target number of participants


Participant exclusion criteria

1. Patients are going to have revision knee surgery
2. Patients are scheduled to have bilateral knee replacement in one sitting
3. Patients suffer from rheumatoid arthritis, diabetes mellitus, post-traumatic arthritis or any form of neurological disorder that can affect the joint position sense
4. Patients have had or will require a major knee arthrotomy on the other same side within six months period
5. Patients have more than 20 degrees of varus, valgus or flexion deformity

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Keele University
Stoke on Trent
United Kingdom

Sponsor information


University Hospital of North Staffordshire NHS Trust (UK)

Sponsor details

Trust Headquarters
Royal Infirmary
Princes Road
Stoke on Trent
United Kingdom

Sponsor type

Hospital/treatment centre



Funder type


Funder name

NHS R&D Funding from the University Hospital of North Staffordshire (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

Study protocol on

Publication citations

  1. Study protocol

    Walley G, Datir S, Sayana M, Rahmatalla A, Dos Remedios I, Wynn-Jones C, Bridgman S, Maffulli N, Anteroposterior glide versus rotating platform low contact stress (LCS) knee arthroplasty: a randomised controlled trial., BMC Musculoskelet Disord, 2007, 8, 87, doi: 10.1186/1471-2474-8-87.

Additional files

Editorial Notes