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Trial registered on ANZCTR


Registration number
ACTRN12622001141730
Ethics application status
Approved
Date submitted
8/08/2022
Date registered
19/08/2022
Date last updated
19/08/2022
Date data sharing statement initially provided
19/08/2022
Type of registration
Prospectively registered

Titles & IDs
Public title
A Multi-centre, Prospective, Clinical Outcomes Study to evaluate the MPRES Stem following primary Total Hip Arthroplasty
Scientific title
A Multi-centre, Prospective, Clinical Outcomes Study to evaluate the MPRES Femoral Stem survivorship (efficacy) following primary Total Hip Arthroplasty
Secondary ID [1] 305580 0
None
Universal Trial Number (UTN)
U1111-1270-5308
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Degenerative osteoarthritis
324000 0
Total Hip Arthroplasty 327383 0
Condition category
Condition code
Musculoskeletal 321506 321506 0 0
Osteoarthritis
Surgery 324505 324505 0 0
Other surgery

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Total Hip Arthroplasty (THA) is a procedure commonly performed in patients who have end-stage hip osteoarthritis. Patients who are planned to undergo THA surgery and fit the eligibility criteria will be considered for enrolment in this study. Each participant will receive the new Medacta MPRES femoral stem device together with a compatible Medacta Acetabular Cup, as part of routine treatment for total hip replacement procedures. These devices will be implanted by qualified and experienced orthopaedic surgeons as per routine practice. The duration of the procedure will take approximately 1-1.5 hours, as per a standard THA. All observational participant data will be collected into an existing electronic App (Patient Optimized Pathway) as per standard protocol. Several patient reported outcome measures (PROMS) in the form of questionnaires, will be collected and analysed during the pre-operative visit and again at 6 month, 1 year, 2 years, 5 years and 10 years time points post-procedure. Each patient will use an electronic data collection phone application which they will download onto their phones and at each timepoint they will log in and complete each of the questionnaires, using their mobile phones. The questionnaires should take up to 30 minutes for the participants to complete. Adherence to the intervention will be monitored through ongoing reviews by the independent expert data safety monitoring board (DSMB). The reviews will include the assessment of the results and any adverse events from the study.
Intervention code [1] 321981 0
Treatment: Devices
Comparator / control treatment
Based on Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) Data Revision notes, the survivorship of the MPRES Femoral Stem at 2, 5 and 10 years post-surgery will be compared to the performance of all other commercially available cementless femoral stems used in Australia for primary total hip replacement procedures. The federally funded AOANJRR captures nearly all joint replacement procedures in Australia as part of Quality Assurance activities, thereby being the most suitable vehicle to allow for direct comparison of revision rates with all other stems. Comparison of the MPRES Femoral stem device will be made to the performance of all other mini stems during the time of which the trial is being conducted (i.e from date of first patient enrolment to date of last patient follow-up time point). This includes other mini stems found in the AOANJRR Registry such as the Smith and Nephew NANOS, Corin Minihip, Zimmer Biomet Taperloc Microplasty and the Mathys optimys. Mini stems are defined by AOANJRR as a short, cementless, femoral components where fixation is destined to be entirely metaphyseal. All mini stems are designed to be bone preserving stems. There are no key differences in the structure and/or function of these devices from the MPRES device. Mean differences in patient reported outcomes measure (PROM) scores (EuroQol five-dimensional scale questionnaire(EQ-5D-5L), Hip disability and osteoarthritis outcome score (HOOS), Visual Analogue Scale(VAS) and Forgotten Joint Score (FJS)) will be obtained pre-surgery and again at 6 months, 1 year, 2 year , 5 years and 10 years post procedure to evaluate the extent of improvement/reduction in patient quality of life, level of pain, satisfaction and rate of complications, compared to scores obtained prior to surgery. Comparison with commercially available implants will be made based on available data and literature, and will not be collected through directly approaching individuals.
Control group
Active

Outcomes
Primary outcome [1] 329276 0
To determine MPRES Femoral Stem survivorship (efficacy) at 2, 5 and 10 years post-operatively compared to all other cementless femoral stems. Survivorship will be assessed by determining the time to first revision surgery required following implantation of the MPRES femoral stem device. These estimates will be calculated using Kaplan-Meier estimates of survivorship. The survivorship data will be sourced and compared to the best performing mini stems currently on the market using the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR).
Timepoint [1] 329276 0
1 year, 2-years (primary time-point), 5 and 10 years post-operatively
Secondary outcome [1] 401983 0
Mean scores on patient reported outcome questionnaire EQ-5D-5L. This questionnaire is
a standardised measure of patient health status and quality of life.
Timepoint [1] 401983 0
6 months, 1 year, 2 years, 5 years and 10 years post-surgery
Secondary outcome [2] 401984 0
Mean scores on patient reported outcome questionnaire Hip Dysfunction and Osteoarthritis Score (HOOS)
Timepoint [2] 401984 0
6 months, 1 year, 2 years, 5 years and 10 years post-surgery
Secondary outcome [3] 401985 0
Mean scores on patient reported outcome questionnaire Visual Analogue Score (VAS) for Pain
Timepoint [3] 401985 0
6 months, 1 year, 2 years, 5 years and 10 years post-surgery
Secondary outcome [4] 401986 0
Mean scores on patient reported outcome questionnaire Forgotten Joint Score
Timepoint [4] 401986 0
6 months, 1 year, 2 years, 5 years and 10 years post-surgery
Secondary outcome [5] 412309 0
Leg Length discrepancy will be measured using x-rays by an independent radiologist.
Timepoint [5] 412309 0
1 year post-surgery.
Secondary outcome [6] 413075 0
Global offset reconstruction will be measured using x-rays by an independent radiologist.
Timepoint [6] 413075 0
1 year post-surgery.
Secondary outcome [7] 413076 0
Stem alignment will be determined using x-rays by an independent radiologist.
Timepoint [7] 413076 0
1 year post-surgery.
Secondary outcome [8] 413077 0
Cup inclination and version will be measured using x-rays by an independent radiologist.
Timepoint [8] 413077 0
1 year post-surgery.
Secondary outcome [9] 413078 0
Stem subsidence will be measured using x-rays by an independent radiologist.
Timepoint [9] 413078 0
6 weeks, 1 year and 2-years post-surgery.
Secondary outcome [10] 413079 0
X-rays will be analysed for Radiolucent lines in the acetabulum and femoral Gruen Zones by an independent radiologist.
Timepoint [10] 413079 0
6 weeks, 1 year and 2-years post-surgery.

Eligibility
Key inclusion criteria
• Male & Females 18-75 years old
• Use of the non TGA approved (pre-market) Medacta MPRES femoral stem prosthesis.
• Ability to give informed consent.
• Qualify for primary total hip arthroplasty surgery with cementless fixation
• Primary diagnosis of non-Inflammatory Degenerative Joint Disease
• Skeletally mature
• Good bone density
• BMI less than or equal to 40.

Minimum age
18 Years
Maximum age
75 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
• Previous hip replacement or fusion on affected side
• Active infection in the affected joint
• Intra-articular fracture
• Neuromuscular or neurosensory deficiency
• Diagnosed metabolic disorder which may impair bone formation or bone quality
• Immunologically suppressed

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised 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
Other design features
The data collected for the MPRES study cohort will be compared to available data on other mini stem devices.
Phase
Not Applicable
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis
Kaplan-Meier estimates of survivorship will be used to describe the time to first revision (or time to death) of the MPRES femoral stem. These estimates are defined as the cumulative percent revision (CPR) at specified years which is the complement (in probability) of the Kaplan-Meier estimates, multiplied by 100. Cumulative percent revision accounts for right censoring due to death and ‘closure’ of the dataset at the time of analysis. Cumulative percent revision is defined as 100 x [1- S(t)] where S(t) is the survivorship probability estimated by the Kaplan-Meier method (see survival curve, below). The cumulative percent revision gives the percent of procedures revised up until time t, and allows for right censoring due to death (but see Cumulative Incidence Function above) or closure of the database for analysis.
The change in patient reported outcomes between pre and post procedure will be analysed using generalised linear mixed models. A normal distribution will be assumed for continuous outcomes (such as HOOS Score). A cumulative logit model will be considered for outcomes where there is a Likert scale (such as EQ-5D-5L). All analysis will be adjusted for age, gender, and BMI.

Recruitment
Recruitment status
Not yet recruiting
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)
NSW,WA,VIC
Recruitment hospital [1] 20796 0
The Avenue Private Hospital - Windsor
Recruitment hospital [2] 20797 0
Hollywood Private Hospital - Nedlands
Recruitment hospital [3] 22876 0
Macquarie University Hospital - Macquarie Park
Recruitment hospital [4] 22877 0
Sir Charles Gairdner Hospital - Nedlands
Recruitment postcode(s) [1] 38182 0
2109 - Macquarie Park
Recruitment postcode(s) [2] 35611 0
3181 - Windsor
Recruitment postcode(s) [3] 35612 0
6009 - Nedlands

Funding & Sponsors
Funding source category [1] 309942 0
Commercial sector/Industry
Name [1] 309942 0
Medacta Australia Pty Ltd
Country [1] 309942 0
Australia
Primary sponsor type
Commercial sector/Industry
Name
Medacta Australia Pty Ltd
Address
Unit A1, 16 Mars Road, Lane Cove, NSW 2066
Country
Australia
Secondary sponsor category [1] 310982 0
None
Name [1] 310982 0
Address [1] 310982 0
Country [1] 310982 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 309660 0
BellBerryLimited
Ethics committee address [1] 309660 0
123 Glen Osmond Road Eastwood Adelaide
South Australia 5063
Ethics committee country [1] 309660 0
Australia
Date submitted for ethics approval [1] 309660 0
01/11/2021
Approval date [1] 309660 0
06/05/2022
Ethics approval number [1] 309660 0
2021-11-1339

Summary
Brief summary
Traditionally, surgeons undertaking THA have performed a distal neck osteotomy, which invariably necessitated the excision of healthy bone. The introduction of bone-conserving short-stem implants has shown there is a growing body of evidence to suggest that retaining the femoral neck can provide mechanical and biological advantages.
One of the aims of successful THA is to restore this environment to its native state. Following surgery, femoral components are subject to high torsional and shear forces that can precipitate implant movement. Torsional stability is known to be an important factor in implant fixation and can influence survivorship. The prostheses are also subjected to vertical forces that can produce interface micro-motion or result in migration of the stem into varus. It is argued that neck preservation offers superior tri-planar implant stability and allows more accurate restoration of the hip biomechanics.
Medacta International have recently developed a new short femoral stem device designed for use in total hip arthroplasty. The femoral stem is one component of a total hip replacement. The MPRES femoral stem is not yet approved by the TGA however, Medacta International has obtained European CE Mark Approval. CE Marking allows Medacta to supply the MPRES device in the European Union (EU).

The MPRES is a Neck Sparing Stem, as it is designed to be bone conserving. It has been designed as a primary uncemented femoral stem for use in total hip arthroplasty. The design intent on the MPRES stem is to provide a THA that preserves healthy bone stock and allow for minimal invasive surgical approaches. The MPRES is a cementless, biplanar, wedge-shaped monoblock stem of Titanium Alloy and hydroxyapatite coating.
It is currently unknown if the new MPRES cementless femoral stem device has noninferiority revision rates in comparison to all other on-market femoral stems. The purpose of this study is to assess the safety and performance of the MPRES. This will be achieved by both assessing the survivorship data and collecting patient reported outcome measures from patients who are having the MPRES device.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 114942 0
Prof Munjed Al Muderis
Address 114942 0
Macquarie Clinic
Suite 303, 2 Technology Place
Macquarie Park, NSW 2109
Country 114942 0
Australia
Phone 114942 0
+61 2 8882 9011
Fax 114942 0
Email 114942 0
munjed@almuderis.com.au
Contact person for public queries
Name 114943 0
Dr Selin Kulaga
Address 114943 0
Medacta Australia Pty Ltd
Unit A1, 16 Mars Road Lane Cove
NSW 2066
Country 114943 0
Australia
Phone 114943 0
+61 1300 361 790
Fax 114943 0
Email 114943 0
selin.kulaga@medacta.com.au
Contact person for scientific queries
Name 114944 0
Prof Munjed Al Muderis
Address 114944 0
Macquarie Clinic
Suite 303, 2 Technology Place
Macquarie Park, NSW 2109
Country 114944 0
Australia
Phone 114944 0
+61 2 8882 9011
Fax 114944 0
Email 114944 0
munjed@almuderis.com.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
To maintain patient confidentiality and comply with international privacy laws, individual participant data will not be available for this trial.


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.