Avenir Müller Hip Stem Post Market Surveillance Study

Study Overview
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Brief Summary
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This study is a Post Market Clinical Follow up study to fulfil the post market surveillance obligations according to Medical Device Directive and European Medical Device Vigilance System (MEDDEV) 2.12-2. The data collected from this study will serve the purpose of confirming safety and performance of the Avenir Müller Hip Stem.

Detailed Description
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The objective of this post market surveillance study is to obtain outcome data on the Avenir Müller Hip Stem by analysis of standard scoring systems, radiographs and adverse event records, and thus to assess the long-term performance and safety of this implant. This is a multi-centre, retrospective post-market surveillance study involving orthopaedic surgeons skilled in hip surgery. Each case enrolled has received the Avenir Müller Hip Stem for a primary hip arthroplasty. The Avenir Müller Hip Stem is CE marked (European Conformity) and commercially available.

Official Title
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A Multi-centre, Non-comparative, Retrospective Post-market Surveillance Study to Obtain Clinical Outcomes Data on the Zimmer Avenir Müller Hip Stem

Conditions
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Osteoarthritis, Hip, Rheumatoid Arthritis, Fracture of Hip, Dislocated Hip, Osteonecrosis, Post-traumatic; Arthrosis, Subluxation Hip

Intervention / Treatment
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* Device: Patients who met the inclusion/exclusion criteria to receive the Avenir Müller stem.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients able to participate in a follow-up program based upon physical examination and medical history. Patients or patient's legal representatives who have given written consent to take part in the study by signing the 'Patient Consent Form'. 18 years minimum. Male and female. Baseline data exist (pre-, peri- and immediate postoperative) Exclusion Criteria: Patients who are unwilling or unable to comply with the follow-up program. Known pregnancy. Patients who are skeletally immature.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients suffering from severe hip pain and disability<br>Patients in need of a total hip arthroplasty. | Device: Patients who met the inclusion/exclusion criteria to receive the Avenir Müller stem.<br>* Consecutive cohort of patients enrolled at every site who received the Avenir Müller stem.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluation of Pain and Functional Performance Determined by the Harris Hip Score | The Harris Hip Score is a questionnaire filled by the surgeon with the patient who received a hip implant. The domains covered are pain, function, absence of deformity, and range of motion. The pain domain measures pain severity and its effect on activities and need for pain medication. The function domain consists of daily activities (stair use, using public transportation, sitting, and managing shoes and socks) and gait (limp, support needed, and walking distance). Deformity takes into account hip flexion, adduction, internal rotation, and extremity length discrepancy. Range of motion measures hip flexion, abduction, external and internal rotation, and adduction. There are 10 items. The score has a maximum of 100 points (best possible outcome) covering pain (1 item, 0-44 points), function (7 items, 0-47 points), absence of deformity (1 item, 4 points), and range of motion (2 items, 5 points). | 10 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Confirmation of Safety Based on Complications | Number of patients with adverse events related to the implant will be reported. Adverse events include: dislocations of the hip, revisions and removals of the implant components. Here, the entire cohort of patients (and hips) enrolled in the study were considered and are reported as the complications occured from the early stages of the study, and up to 10 year post surgery, and could occur to any patients. | up to 10 years | 
| Survivorship of the Implant | Implant survival based on removal or intended removal of the device and determined using the Kaplan-Meier method. Here, the entire cohort of patients (and hips) enrolled in the study were considered and are reported as the revisions could happen from the early stages of the study, and up to 10 year post surgery, and could occur to any patients. Even if a patient did not come back for a visit, the information if the implant was still in place was provided and taken into account for the survival analysis (gives higher numbers than for the clinical evaluation). | 10 years |