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Trial registered on ANZCTR


Registration number
ACTRN12613001278729
Ethics application status
Approved
Date submitted
18/11/2013
Date registered
19/11/2013
Date last updated
1/04/2019
Date data sharing statement initially provided
1/04/2019
Date results information initially provided
1/04/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
A prospective randomised controlled trial investigating three dimensional knee joint kinematics in total knee replacement – a comparison of cruciate retaining, posterior cruciate sacrificing and medially stabilised designs.
Scientific title
A prospective randomised controlled trial investigating three dimensional knee joint kinematics in patients with osteoarthritis undergoing total knee replacement – a comparison of cruciate retaining, posterior cruciate sacrificing and medially stabilised designs.
Secondary ID [1] 283612 0
Nil
Universal Trial Number (UTN)
Trial acronym
Medacta knee kinematics
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Osteoarthritis
290536 0
Condition category
Condition code
Musculoskeletal 290934 290934 0 0
Osteoarthritis
Surgery 290942 290942 0 0
Surgical techniques

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
All participants in this trial will receive a total knee replacement. The prosthesis used will be the GMK Total Prosthesis from Medacta International SA.
Randomisation will allocate patients to have one of three different types of prosthesis from this suite of prostheses.
These are (1) posterior cruciate ligament retaining prosthesis, (2) a posterior cruciate ligament sacrificing/subsituting prosthesis and (3) a medially stabilised prosthesis - the GMK Sphere.
The key differences between these prostheses is the level of antero-posterior constraint and the way in which the posterior cruciate ligament is handled.
The approximate duration for knee replacement surgery is 90 minutes, the standard operative time for all elective knee replacement surgery, regardless of the device being utilised.
Intervention code [1] 288304 0
Treatment: Surgery
Comparator / control treatment
Group 1 will receive a Cruciate retaining prosthesis
Group 2 will receive a Posteriorly stabilising prosthesis
Group 3 will receive a Medially Stabilizing prosthesis

Group 1 is the most commonly used technique in Australia and will thus be considered the control.
Control group
Active

Outcomes
Primary outcome [1] 290917 0
The primary outcome will be to assess in vivo three dimensional knee kinematics for three different fixed-bearing total knee replacement prostheses.
Joint motion, ground reaction forces and muscle activity will be recorded simultaneously from each subject using an x-ray machine during four test conditions; level walking, stair ascent. stair decent and chair raise.
Timepoint [1] 290917 0
6 months post operatively
Secondary outcome [1] 305593 0
Limb Alignment - x-ray and computed tomography imaging
Timepoint [1] 305593 0
6 months post-operatively
Secondary outcome [2] 305594 0
Knee Pain and Function
-will be measured using the New International Knee Society Score and the Oxford Knee Score Surveys plus a Six-minute-walk-test plus timed-up-go assessments
Timepoint [2] 305594 0
Pre-operatively, 6 and 12 months post-operatively

Eligibility
Key inclusion criteria
i) on the waiting list for primary total knee replacement due to osteoarthritis at St Vincent's Hospital, Melbourne
ii) knee replacement performed by one of three joint replacement surgeons at St Vincent's Hospital whose prosthesis of choice is the Medacta GMK Knee System
Minimum age
18 Years
Maximum age
85 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
i) Surgery for neoplastic disease
ii) Inability to provide informed consent

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)
When a subject has fullfilled all study criteria allocation takes place. The patients assignment will be performed by the data manager who will have no direct contact with the subject either before or after assignment. The clinicians involved in the assessment of patients will have no role in the assignment process. The randomisation schedule will be revealed by telephone following informed consent.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The randomisation schedule will be generated and maintained centrally by one of the investigators who will not be involved in assessment of participants.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
No prior studies exist to base sample size calculation for 3-D fluoroscopic gait analysis. Therefore, our randomised control trial is powered (alpha value = 0.05 and power = 90%) to answer our secondary aim of determining whether a medially stabilised design will result in improved functional outcomes following knee replacement compared to a fixed-bearing cruciate retaining design. Functional outcomes will be measured at 12 months post knee replacement using the Oxford Knee Score (OKS). To demonstrate a difference of 5.0 (SD 5.0) in OKS between groups, 25 participants in each arm will be required. We will recruit 30 per arm to account for an approximate drop out rate of 20%.
Categorical variables will be analysed using chi-squared tests (or Fisher's Exact tests for small samples) while continuous variables will be apllied to (paramatric) t-tests and (non-parametric) Mann-Whitney tests for symetrically and asymmetrically distributted data, respectively. Multivariate analysis will be run to account for confounding variables.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC
Recruitment hospital [1] 1748 0
St Vincent's Hospital (Melbourne) Ltd - Fitzroy
Recruitment postcode(s) [1] 7563 0
3065 - Fitzroy

Funding & Sponsors
Funding source category [1] 288294 0
Commercial sector/Industry
Name [1] 288294 0
Medacta International SA
Address [1] 288294 0
Strada Regina
CH-6874 Castel San Pietro
Country [1] 288294 0
Switzerland
Primary sponsor type
Individual
Name
Professor Peter Choong
Address
Department of Orthopaedics
St Vincent's Hospital, Melbourne
Level 3 Daly Wing
35 Victoria Pde
Fitzroy Victoria 3065
Country
Australia
Secondary sponsor category [1] 287015 0
Individual
Name [1] 287015 0
Professor Marcus Pandy
Address [1] 287015 0
Department of Biomechanical Engineering
University of Melbourne
Level 5
161 Barry Street
Parkville, 3010
Victoria
Country [1] 287015 0
Australia
Secondary sponsor category [2] 302268 0
Individual
Name [2] 302268 0
Associate Professor. Michelle Dowsey
Address [2] 302268 0
Department of Orthopaedics
3rd Floor, Daly Wing
Fitzroy
Victoria 3065
Country [2] 302268 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 290191 0
St Vincent's Hospital (Melbourne) Human Research Ethics Committee - D
Ethics committee address [1] 290191 0
Ethics committee country [1] 290191 0
Australia
Date submitted for ethics approval [1] 290191 0
Approval date [1] 290191 0
25/11/2013
Ethics approval number [1] 290191 0

Summary
Brief summary
This is an investigator initiated study, aiming to assess the prosthetic performance of total knee replacements (TKR) and to determine whether abnormal movement of the replaced knee has an impact upon function and pain at one year post-operatively.
By using a prospective analysis of patients randomized to receive TKR of different designs, this study aims to determine the effect the type of prosthesis has on gait, three-dimensional joint movement plus both clinical and patient reported outcomes.
In order to achieve this, joint motion, ground reaction forces and muscle activity will be recorded simultaneously from each subject during four test conditions; level walking, stair ascent, stair descent and chair rise. Limb alignment, pain and functional assessments will also be evaluated, to assist in determining variables associated with improved functional outcomes following TKR.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 44410 0
Prof Peter Choong
Address 44410 0
Department of Orthopaedics
St Vincent's Hospital Melbourne
Level 3 Daly Wing
35 Victoria Parade
Fitzroy Victoria 3065
Country 44410 0
Australia
Phone 44410 0
+61 3 9288 3980
Fax 44410 0
Email 44410 0
sarcoma@bigpond.net.au
Contact person for public queries
Name 44411 0
Dr Dr Tony Young
Address 44411 0
Department of Orthopaedics
St Vincent's Hospital Melbourne
Level 3 Daly Wing
35 Victoria Parade
Fitzroy Victoria 3065
Country 44411 0
Australia
Phone 44411 0
+61 3 9288 2364
Fax 44411 0
Email 44411 0
tony.young@svha.org.au
Contact person for scientific queries
Name 44412 0
Dr Tony Young
Address 44412 0
Department of Orthopaedics
St Vincent's Hospital Melbourne
Level 3 Daly Wing
35 Victoria Parade
Fitzroy Victoria 3065
Country 44412 0
Australia
Phone 44412 0
+61 3 9288 2364
Fax 44412 0
Email 44412 0
tony.young@svha.org.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Consent for data sharing was not obtained and ethics approval would be required from the study institution for future use of patient level data
What supporting documents are/will be available?
No other documents available
Summary results
Have study results been published in a peer-reviewed journal?
No
Other publications
Have study results been made publicly available in another format?
No
Results – basic reporting
Results – plain English summary