Clinical and Functional Outcome of the GEMINI SL Fixed Bearing PS Knee Prosthesis

Study Overview
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Brief Summary
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This is a prospective, multicenter, observational study with a planned follow-up period of 10 years to confirm the safety and performance of the GEMINI SL Fixed Bearing PS knee prosthesis in longterm follow-up under routine conditions. Primary outcome of the study is the 10-year survival rate of the GEMINI SL Fixed Bearing PS knee prosthesis with revision for any reason as the endpoint.

Detailed Description
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The GEMINI SL Fixed Bearing PS knee prosthesis combines clinical proven design features with state-of-the-art-technology in order to achieve a high standard clinical performance, surgical efficiency and safety. Currently, no mid- and longterm clinical data are available for the GEMINI SL Fixed Bearing PS knee prosthesis. Therefore, the study is designed to generate clinical data of the GEMINI SL Fixed Bearing PS knee prosthesis in the 10-year follow-up under routine condition.

Official Title
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Clinical and Functional Outcome of the GEMINI SL Fixed Bearing PS Knee Prosthesis in Short-, Mid-, and Longterm Follow-up

Conditions
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Osteoarthrosis of Knee

Intervention / Treatment
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* Device: Total knee replacement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Signed patient informed consent Implantation of a GEMINI SL Fixed Bearing PS knee prosthesis Age between 18 and 80 years Exclusion Criteria: Body Mass Index (BMI) > 40 kg/m² Foreseeable life expectancy under 5 years Comorbidities and known medical circumstances which would affect the clinical or functional outcome after implantation of the knee prosthesis (e.g. neurological or musculoskeletal diseases) at the time of implantation Patient who is mentally not able to understand the study and the study conduct Patients who will be foreseeable non-compliant to the planned routine interventions and study related follow-ups Prisoner Pregnant women

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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

| Intervention/Treatment |
| --- |
|Device: Total knee replacement|Implantation of the GEMINI SL Fixed Bearing PS knee prosthesis. The operation technique of the GEMINI SL Fixed Bearing PS knee prosthesis will be followed.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 10-year survival rate of the Gemini SL Fixed Bearing PS knee prothesis | Primary outcome of the study is the 10-year survival rate of the Gemini SL Fixed Bearing PS knee prosthesis with revision for any reason as the endpoint. Revisions are defined as removal, exchange or adding of any implant components. The definition does not include subsequent implantations or exchange of the patella component or the polyethylene plateau. Survival rate will be calculated according to the method of Kaplan-Meier. | 10 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Survival rate of the GEMINI SL Fixed Bearing PS knee prosthesis | Survival rate of the GEMINI SL Fixed Bearing PS knee prosthesis after 6 months, 1, 3 and 5 years | after 6 months, 1,3 and 5 years | 
| Change in functional and clinical outcome (KOOS) | Evaluation of the change in functional and clinical outcome from preoperative to 6 months, 1, 3, 5 and 10 years postoperative, measured by the Knee injury and Osteoarthritis Outcome Score (KOOS). The KOOS is a reliable and validated knee-specific patient-administered outcome instrument. The previous week is taken into consideration when answering the questions. Standardized answer options are given (5 Likert boxes) and each question gets a score from 0 (best result) to 4 (worst result). The KOOS consists of 5 sub-scales: Pain, Symptoms, Function in daily living (ADL), Function in sport and recreation (Sport/Rec) and Hip/Knee related Quality of life (QoL). A normalized score (100 indicating no symptoms and 0 indicating extreme symptoms) is calculated for each subscale. | preoperative examination to postoperative examinations after 6 months, 1, 3, 5 and 10 years | 
| Change in functional and clinical outcome (KSS) | Evaluation of the change in functional and clinical outcome from preoperative to 6 months, 1, 3, 5 and 10 years postoperative, measured by the Knee Society Score (KSS). The KSS is a frequently used, reliable and validated score in the assessment of a subject's knee pain and functional knee capacity. It comprises two arms, the functional ability and the clinical examination score, each ranging from 0 points (worst result) to 100 points (best result). | preoperative examination to postoperative examinations after 6 months, 1, 3, 5 and 10 years | 
| Complications rate | Complications related to implantation of the GEMINI SL Fixed Bearing PS knee prosthesis (infections, dislocations, migrations, aseptic loosenings, periprosthetic fractures, intra-operative fractures, implant fractures, soft tissue fractures, joint instability etc.) will be recorded at all follow-up examinations. | Intraoperative examinations to 10-year follow-up examination | 
| Subsequent surgical interventions | All subsequent surgical interventions at the operated knee (exchange of the polyethylene plateau, additional implantation/exchange of the patella component, soft-tissue balancing, debridement etc) will be recorded at all follow-up examinations. | postoperative examinations up to 10-year follow-up examination |