An observational study in Arthritis (Hip) and Hip Dysplasia, Congenital, sponsored by Medacta International SA. Recruiting at 1 site in France. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-10-07.
Sponsored by Medacta International SA · Observational
The goal of this observational study is to collect clinical and radiological data to monitor the safety and performance of the ROMAX hip resurfacing system. The main parameter that will be measured is the rate of revisions at 10 years.
This single-center, post-market, prospective, longitudinal, and uncontrolled cohort study aims to evaluate the survival rate of the Medacta ROMAX hip resurfacing system, particularly focusing on dislocations and the potential consequences of wear over a 10-year period. Additionally, the study will assess clinical performance through patient-reported outcomes (PROMs) and analyze the migration behavior of the device using the CTMA method in a subgroup of 40 patients. The study will include a total of 150 cases, with 40 patients undergoing CTMA analysis at 3 years post-surgery. Eligible patients will be informed during preoperative visits and included upon signing the consent form, prior to surgery. Participation in the CTMA subgroup is optional and does not affect overall study inclusion. Follow-ups will be conducted at 3 months, 1, 3, 5, and 10 years. Data collection will include clinical scores, clinical and radiological data related to preoperative and postoperative status, and perioperative surgical details.
843 studies on the registry are indexed under Arthritis; 118 are open to participants now.
This study's planned enrollment of 150 is close to the median of 151 across 202 observational studies indexed under Arthritis.
Browse Arthritis studies →Medacta International SA is the lead sponsor of 46 studies on the registry; 18 are open to participants now.
Counted across the registry records on this site, refreshed daily.
150 patients undergoing hip resurfacing surgery and receiving the ROMAX system will be recruited consecutively by the study investigator. All patients will be offered to join the CTMA subgroup until the number of 40 subjects is reached. Choosing not to participate in the CTMA subgroup will not prevent the patient from participating in the study.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Patients undergoing hip resurfacing surgery with ROMAX system
Device: Hip resurfacing system
Hip resurfacing with ROMAX system
Implant survival
Survival of the implant through Kaplan-Meier analysis based on revisions
Time frame: 10 years
Harris Hip Score (HHS)
Measure of dysfunction ranging from 0 to 100, where higher values represent better outcomes.
Time frame: 3 months, 1 year, 3 years, 5 years, 10 years
Forgotten Joint Score (FJS)
Patient-reported outcome measure that evaluates joint dysfunction. It ranges from 0 to 100, with higher scores indicating better outcomes
Time frame: 3 months, 1 year, 3 years, 5 years, 10 years
Postel-Merle d'Aubigné Score (PMA)
Clinical rating system used to assess hip function. It ranges from 0 to 18, with higher scores indicating better hip function and fewer limitations in activities.
Time frame: 3 months, 1 year, 3 years, 5 years, 10 years
Oxford Hip Score (OHS)
Patient-reported outcome measure designed to assess hip function and pain. It ranges from 0 to 48, with higher scores indicating better function and less pain.
Time frame: 3 months, 1 year, 3 years, 5 years, 10 years
UCLA Activity Scale
Questionnaire assessing physical activity level from 1 (low) to 10 (high).
Time frame: 3 months, 1 year, 3 years, 5 years, 10 years
HOOS (Hip injury and Osteoarthritis Outcome Score) Symptoms subscale
Patient-reported outcome measure comprising 5 questions assessing hip joint symptoms and stiffness. It ranges from 0 to 100, with higher values indicating better outcomes.
Time frame: 3 months, 1 year, 3 years, 5 years, 10 years
Radiologic Evaluation
Assessment of implant positioning and radiographic appearence.
Time frame: 3 months, 1 year, 3 years, 5 years, 10 years
CT-micromotion analysis (CTMA)
CT-based evaluation of implant movement and wear. Will be performed on a subgroup of patients (40)
Time frame: 3 months, 1 year, 3 years
Plan to share: No
No publications or documents are linked to this record.
Started Jul 2025 (actual). Primary completion is estimated for Apr 2037, 140 months after the start.
Of 87 observational studies under Arthritis, half reached primary completion within 83 months of starting (the median), counting those still running; a quarter within 33 and three quarters within 223. This study's planned 140 months is above that.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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