Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12615000550505
Ethics application status
Approved
Date submitted
17/05/2015
Date registered
29/05/2015
Date last updated
20/03/2019
Date data sharing statement initially provided
20/03/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
Total knee arthroplasty with comparison of inset versus onlay patella replacement: investigation of anterior knee pain and function.
Scientific title
In patients with knee osteoarthritis requiring total knee arthroplasty, does patella replacement with an inset design prosthesis, compared with an onlay design prosthesis, improve anterior knee pain and function?
Secondary ID [1] 286727 0
Nil
Universal Trial Number (UTN)
U1111-1170-2525
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Knee Osteoarthritis 295089 0
Total Knee Arthroplasty 295090 0
Knee pain 295092 0
Knee function 295093 0
Condition category
Condition code
Surgery 295339 295339 0 0
Surgical techniques
Musculoskeletal 295415 295415 0 0
Osteoarthritis

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Zimmer NexGen(Registered Trademark) Posterior Stabilised Total Knee Arthroplasty System. Either Inset or Onlay design NexGen(Registered Trademark) patella components.
Intervention code [1] 291887 0
Treatment: Surgery
Comparator / control treatment
Inset design
Control group
Active

Outcomes
Primary outcome [1] 295092 0
Knee pain assessed with validated scoring questionnaires: (Oxford Knee Score - OKS, Knee injury and Osteoarthritis Outcome Score - KOOS, Patient Satisfaction Questionnaire - PSQ, Visual Acuity Scale - VAS)
Timepoint [1] 295092 0
Pre-operation (baseline) and 3, 6, 12, 24, and 60 months post-operation
Secondary outcome [1] 314749 0
Knee functional scores using validated scoring questionnaires: (Oxford Knee Score - OKS, Knee injury and Osteoarthritis Outcome Score - KOOS, Patient Satisfaction Questionnaire - PSQ)
Timepoint [1] 314749 0
Pre-operation (baseline) and 3, 6, 12, 24, and 60 months post-operation
Secondary outcome [2] 314750 0
Knee Function Testing: (Active knee flexion and extension range of motion; timed stair ascend and descend; and Step test)
Timepoint [2] 314750 0
Pre-operation (baseline) and 3, 6, 12, 24, and 60 months post-operation

Eligibility
Key inclusion criteria
45-80 years; planning to undergo primary total knee arthroplasty for knee osteoarthritis with at posterior stabilised prostheses; willing to participate in the trial and follow up; under the care of Prof Wood at Hollywood Private Hospital, Western Australia.
Minimum age
45 Years
Maximum age
80 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Revision total knee arthroplasty; previous high tibial osteotomy; total knee arthroplasty for non-osteoarthritic pathology; Age <45years or >80years; participant refusal to participate or sign informed consent; participant incapable or unable to participate with the clinical questionnaires or knee function assessments.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Following Hollywood Hospital ethics approval, this project will recruit suitable and consenting participants from the private rooms of Prof. D Wood at the Perth Orthopaedic Institute, Hollywood Private Hospital. Potential participants fulfilling the inclusion criteria and without the exclusion criteria, will be provided with written information regarding the trail and given the opportunity to ask questions. Those willing to participate will sign informed consent and then be randomised to one of the two groups (inset patella component, or onlay patella component). The randomisation and allocation to treatment groups will be completed using a random number generator (www.random.org) by a different investigator to the investigator enrolling participants. Participants will be blinded as to their group. Consenting participants would then undergo their total knee arthroplasty based on their group, and then be followed up equally.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
A web-based random number generator (www.random.org) will be used to place participants in one of the two groups. The random numbers are generated based on atmospheric noise, which is arguably more random than simple randomisation using computer driven sequence generation.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis
A priori power calculation has been determined using GPOWER (GPOWER Version 3.1.5, Bonn University, Bonn, Germany). This has demonstrated that for an anticipated moderate effect size (d = 0.50) in the primary outcome variable (pain subscale of the KOOS), a total of 64 knees (32 in each intervention group) is required to reveal differences at the 5% significance level, with 80% power. In order to account for a 20% drop-out per group over the 5 year evaluation period, a minimum total of 78 (39 patients per group) will be recruited into this trial.

Scores from the questionnaires and knee function tests will be collected for each patella group and compared using SPSS or equivalent data software. The purpose will be to generate hazard ratios and confidence intervals looking for significant differences at p<0.05.

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
1/07/2016
Actual
6/02/2017
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
100
Accrual to date
42
Final
Recruitment in Australia
Recruitment state(s)
WA
Recruitment hospital [1] 3802 0
Hollywood Private Hospital - Nedlands
Recruitment postcode(s) [1] 9689 0
6009 - Nedlands

Funding & Sponsors
Funding source category [1] 291285 0
Commercial sector/Industry
Name [1] 291285 0
Zimmer
Country [1] 291285 0
Australia
Primary sponsor type
Individual
Name
Dr Chadwick Green
Address
Perth Orthopaedics Institute,
Entrance 6 Verdun Street
Nedlands, Western Australia, 6009

All mail to: PO Box 4078, Wembley, WA, 6913
Country
Australia
Secondary sponsor category [1] 289960 0
Individual
Name [1] 289960 0
Prof. David Wood
Address [1] 289960 0
Perth Orthopaedics Institute,
Entrance 6 Verdun Street
Nedlands, Western Australia, 6009
Country [1] 289960 0
Australia
Secondary sponsor category [2] 289962 0
Individual
Name [2] 289962 0
Dr Jay Ebert
Address [2] 289962 0
The Hollywood Functional Rehabilitation Clinic
C/O Perth Orthopaedic Institute, Hollywood Private Hospital
Entrance 6 Verdun Street, Nedlands, Perth, WA, 6009
Country [2] 289962 0
Australia
Secondary sponsor category [3] 289963 0
Hospital
Name [3] 289963 0
Hollywood Private Hospital
Address [3] 289963 0
Monash Ave, Nedlands WA 6009
Country [3] 289963 0
Australia
Secondary sponsor category [4] 302160 0
Individual
Name [4] 302160 0
Dr David Wysocki
Address [4] 302160 0
Sir Charles Gairdner Hospital
Department of Orthopaedics
Locked Bag 2012
Nedlands WA 6009
Country [4] 302160 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 292851 0
Hollywood Hospital Research Ethics Committee
Ethics committee address [1] 292851 0
Hollywood Hospital
Monash Ave, Nedlands WA 6009
Ethics committee country [1] 292851 0
Australia
Date submitted for ethics approval [1] 292851 0
25/05/2015
Approval date [1] 292851 0
17/03/2016
Ethics approval number [1] 292851 0
HPH421

Summary
Brief summary
The aim of this trial is to compare current patella component designs (inset vs onlay), with the hope of finding significant improvement in anterior knee pain or knee function for one design over the other. Subsequently, future patients can benefit from surgery using the superior design.

This trial will recruit suitable and consenting participants from the private rooms of Prof. D Wood at the Perth Orthopaedic Institute, HPH. Consenting participants would undergo a total knee arthroplasty (which they otherwise would undergo, whether they were enrolled in this study or not, as part of their clinical care). The patella component of their total knee arthroplasty (TKA) will be randomised to either an inset design or onlay design. All surgeries will be carried out by Prof. D Wood using his routine surgical technique and peri-operative care. Participants are not placed at increased risk or offered inferior treatment in this study based on current knowledge.

Participants will have standard postoperative weekly physiotherapy sessions as part of the standard care following total knee arthroplasty, and will be followed up by Prof Wood at 3, 6, 12, 24 and 60 months, also as part of usual care. During this interval follow up, participants will also complete a series of validated scoring questionnaires and functional tests, administered by a trained assessor.

These functional data will be compared across the two study groups (inset patella component, onlay patella component) and hazard ratios and confidence intervals generated using statistical software. Anonymous results will be submitted for publication in a leading orthopaedic journal to inform other surgeons and medical professionals of the results.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 57326 0
Dr Chadwick Green
Address 57326 0
Perth Orthopaedics Institute,
Entrance 6 Verdun Street
Nedlands, Western Australia, 6009

All Mail to: PO Box 4078, Wembley, WA 6913
Country 57326 0
Australia
Phone 57326 0
+61 8 93866211
Fax 57326 0
Email 57326 0
cjgreen85@gmail.com
Contact person for public queries
Name 57327 0
Dr Chadwick Green
Address 57327 0
Perth Orthopaedics Institute,
Entrance 6 Verdun Street
Nedlands, Western Australia, 6009
Country 57327 0
Australia
Phone 57327 0
+61 8 93866211
Fax 57327 0
Email 57327 0
cjgreen85@gmail.com
Contact person for scientific queries
Name 57328 0
Dr cjgreen85@gmail.com
Address 57328 0
Perth Orthopaedics Institute,
Entrance 6 Verdun Street
Nedlands, Western Australia, 6009
Country 57328 0
Australia
Phone 57328 0
+61 8 93866211
Fax 57328 0
Email 57328 0
cjgreen85@gmail.com

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Not approved by Ethics Committee


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.