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Trial details imported from

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Registration number
Ethics application status
Date submitted
Date registered
Date last updated

Titles & IDs
Public title
A Trial Evaluating TKR Compared to BKR Performed Using Stryker's Mako Robot
Scientific title
A Prospective, Randomised Controlled Trial Evaluating Total Knee Replacement With the Stryker Triathlon Primary Total Knee System, Compared to Bicompartmental Knee Replacement With Restoris MCK Multicompartmental Knee System Performed Using Stryker's Robotic-arm Assisted Surgery System, Mako
Secondary ID [1] 0 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Non-inflammatory Degenerative Joint Disease 0 0
Condition category
Condition code
Musculoskeletal 0 0 0 0
Other muscular and skeletal disorders
Musculoskeletal 0 0 0 0

Study type
Description of intervention(s) / exposure
Treatment: Devices - Stryker Triathlon Primary Total Knee System
Treatment: Devices - Restoris MCK Multicompartmental Knee System

Other: Bicompartmental Knee Replacement (BKR) - Receiving Restoris MCK Multicompartmental Knee System for Bicompartmental Knee Replacement (BKR). Surgery performed using Stryker's robotic-arm assisted surgery system Mako

Other: Total Knee Replacement (TKR) - Receiving Stryker Triathlon Primary Total Knee System for Total Knee Replacement. Surgery performed using conventional instrumentation or navigation.

Treatment: Devices: Stryker Triathlon Primary Total Knee System
Total Knee Replacement

Treatment: Devices: Restoris MCK Multicompartmental Knee System
Bicompartmental Knee Replacement

Intervention code [1] 0 0
Treatment: Devices
Comparator / control treatment
Control group

Primary outcome [1] 0 0
Oxford Knee Score - Comparing clinical outcomes using the Oxford Knee Score. The OKS is a participant completed 12 question form on activities of daily living that assess function and pain. Scores can range from 0 to 48 with lower scores indicating a poor outcome and higher scores indicating a more satisfactory joint outcome.
Timepoint [1] 0 0
24 months/ 2 years
Secondary outcome [1] 0 0
Health related quality of life EQ-5D - Comparing functional and clinical outcomes using the EQ-5D. The EQ-5D-3L descriptive system comprises the following 5 dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. Each dimension has 3 levels: no problems, some problems, extreme problems. The participant is asked to indicate his/her health state by indicating the most appropriate level for each of the 5 dimensions. Responses may be converted into a single summary index by applying a formula that essentially attaches values (also called weights) to each of the levels in each dimension. The index can be calculated by deducting the appropriate weights from 1= the value for full health. The EQ VAS records the participant's self-rated health on a vertical, visual analogue scale where the endpoints are labelled from 100 ='Best imaginable health state' to 0= 'Worst imaginable health state'.
Timepoint [1] 0 0
24 months/ 2years
Secondary outcome [2] 0 0
VAS pain - Comparing functional and clinical outcomes using the VAS pain. Pain at rest and pain during mobilization are measured using a 10 centimeter Visual Analogue Scale (VAS). Participants are asked to indicate their level of pain with 0 being no pain and 100 being the worst pain.
Timepoint [2] 0 0
24 months/ 2years
Secondary outcome [3] 0 0
New Knee Society Score (KSS) - Comparing functional and clinical outcomes using the KSS. The Knee Society Clinical Rating System is comprised of two distinct sub-scores: one for pain, range of motion (ROM) and joint stability, and one for functional parameters. Sub-scores range from a minimum score of 0 to a maximum of 100 points. Although the specific scores are not distinguished as "excellent," "good," "fair," or "poor," a higher value represents a better outcome.
Timepoint [3] 0 0
24 months/ 2years
Secondary outcome [4] 0 0
Forgotten Joint Score (FJS) - Comparing functional and clinical outcomes using the FJS. The Forgotten Joint Score (FJS) is a 12 question form that asks the patient their level of awareness of their artificial joint in 12 scenarios commonly encountered in daily life. Scores can range from 0 to 100 with a higher score indicating a better outcome (high degree of forgetting the joint in everyday life).
Timepoint [4] 0 0
24 months/ 2years
Secondary outcome [5] 0 0
Incidence of loosening, reoperation and revision - To compare incidence of loosening, reoperation and revision rates. The incidence (ie number of participants who experienced lossening, reoperation or revision) will be counted and presented as a whole number or percentage of the total number of patients, however they will be identified from analysing Xrays and checking Serious Adverse Event/ Adverse Event reports.
Timepoint [5] 0 0
6 weeks, 3 months, 12 months, 24 months
Secondary outcome [6] 0 0
Length of Hospital Stay - To compare length of hospital stay between the two arms of the study
Timepoint [6] 0 0
6 weeks

Key inclusion criteria
1. The patient is a suitable candidate for a Bicompartmental Knee Replacement and has
moderate to severe patellofemoral wear and medial compartment wear (surgeons

2. The patient has no fixed flexion greater than 10 degrees.

3. The patient has maximal flexion greater than 100 degrees

4. The patient has a passively correctable varus deformity

5. The patient has a functionally Intact Anterior Cruciate Ligament (ACL.)

6. The patient has no significant patellofemoral malalignment

7. The patient has negligible lateral compartment degeneration with no appreciable loss
of cartilage height (surgeon's discretion).

8. The patient has pain that is not localised to the medial compartment only

9. The patient is a male or non-pregnant female.

10. The patient has signed the study specific, Human Research Ethics Committee (HREC)-
approved Informed Consent document and is willing and able to comply with the
specified pre-operative and post-operative clinical and radiographic evaluations
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
1. The patient has a clinically deficient ACL and cruciate and collateral ligament
insufficiency on CT arthrogram.

2. The patient is undergoing revision surgery

3. The patient has greater than 10° of hyperextension, greater than 10° of varus or
valgus deformity, greater than 10° Flexion Contracture

4. The patient has active, local infection or previous intra-articular infection

5. The patient has skeletal immaturity

6. The patient is without sufficient bone stock to allow appropriate insertion and
fixation of the prosthesis

7. The patient's weight, age or activity level might cause extreme loads and early
failure of the system (surgeons discretion).

8. The patient has a systemic or local condition that would limit the ability to assess
the performance of the device e.g. neuromuscular or neurosensory deficiency, disorder
leading to progressive bone deterioration (including rheumatoid arthritis and
osteoporosis), or patient is immunologically suppressed.

9. Patient has a cognitive impairment, an intellectual disability or a mental illness
that is considered by the investigator to inhibit the patient's capacity to consent to
research and the ability to participate in it

10. Patients with tricompartmental disease are contraindicated from the study

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 0 0
Perth Hip & Knee - Subiaco
Recruitment postcode(s) [1] 0 0
6008 - Subiaco

Funding & Sponsors
Primary sponsor type
Commercial sector/Industry
Stryker South Pacific

Ethics approval
Ethics application status

Brief summary
A prospective, randomised controlled trial evaluating Total Knee Replacement with the Stryker
Triathlon Primary Total Knee System, compared to Bicompartmental Knee Replacement with
Restoris MCK Multicompartmental Knee System performed using Stryker's Robotic-arm assisted
surgery system, Mako.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 0 0
Address 0 0
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Holly Solomon
Address 0 0
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for scientific queries

Summary results
For IPD and results data, please see