Monocer AOANJRR Registry-nested Study

This study titled "Prospective, Multicentre Study to Assess Performance of the MonoCer Acetabular Cup in Primary Total Hip Replacement" is a multi-centre prospective registry-nested cohort study, using AOANJRR's web-based data collection system integrated with Registry data collection, designed to assess the ten-year clinical outcome of the MonoCer Acetabular Cup in Primary Total Hip Replacement. The primary outcome measure is mortality and secondary measures are PROMs and complications.

The purpose and objectives of this study are to assess and document the clinical outcomes in a group of primary total hip arthroplasty patients having this surgery for the management of end-stage osteoarthritis. Survivorship and changes in pain and function as well as death will be assessed. The design of this study will also allow, if required the continued follow-up after the initial 2 years to determine mid and long-term survivorship and performance of this cohort.

All patients will receive primary hip arthroplasty standard of care (pre and post operatively) as defined by each participating surgeon. In addition to the Medacta MonoCer Acetabular Cup. There shall be no investigational, experimental or "off-label" use of the device. There will be no experimental or investigational devices used. There will be no experimental or investigational surgical techniques used. The devices and products will be used in accordance with their instructions for use and/or approved labelling.

A prospective study will be conducted using the AOANJRR web-based data collection system (RAPID). Eligible and consented participants are registered in the RAPID system. The PROMs will be completed by patients via the RAPID system.

• Surgeons will determine patient eligibility, providing informed consent prior to enrolment and registration in RAPID.

Participating sites will send procedure data to the AOANJRR as per standard practice, this data is then linked to the study participant. All data will be stored in a secure data repository.

* A minimum of 280 patients will be recruited over an 18-month period. * All data will be integrated with routinely collected Registry data.