Oxford Signature vs. Conventional Global Study

Study Overview
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Brief Summary
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This study will compare alignment criteria in the Oxford Partial Knee using conventional instrumentation and Signature Custom Guides in order to determine if the use of the Signature Custom Guides results in a higher percentage of knees achieving optimal alignment. The study will also examine outcomes with high volume surgeons (>30 cases/year) and low volume surgeons (<10 cases/year).

Detailed Description
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The primary objectives of this global clinical study are to collect data to assess the following clinical evidence parameters that were gathered from Biomet team members and KOL globally for this product: Evaluate the performance & accuracy of the Oxford Partial Knee System with Signature Knee Guide in comparison to conventional instrumentation. Compare the accuracy of Signature Guides between two user profiles: high volume surgeons & low volume surgeons in a global mix. Assess potential economic & efficiency advantages in the short term and long-term: OR efficiency, patient quality of life and activity, clinical outcomes.

Official Title
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A Global Comparison of Signature Guides and Conventional Instrumentation in the Oxford Partial Knee

Conditions
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Osteoarthritis, Osteoarthritis, Knee, Osteonecrosis

Intervention / Treatment
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* Device: Signature Custom Guides
* Procedure: Conventional Instrumentation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Intended for use in individuals with osteoarthritis or Avascular necrosis limited to the medial compartment of the knee that is also lacking patellofemoral or lateral compartment disease. Use of cementless femoral fixation is permitted outside of the United States if it complies with all local, state, and/or national and international regulations. The same technique must be used consistently throughout the course of the study with all cases Patients 21 and over Exclusion Criteria: Use of Cementless Fixation in the United States Infection, sepsis or osteomyelitis Use in lateral compartment of the knee Rheumatoid arthritis or other forms of inflammatory joint disease Revision of failed prosthesis, failed upper tibial osteotomy, or post traumatic arthritis after tibial plateau fracture Insufficiency of the collateral, anterior, or posterior cruciate ligaments which would preclude stability of the device. Disease or damage to the lateral compartment of the knee Uncooperative patient or patient with neurologic disorders who is incapable of following directions Osteoporosis in the United States / Insufficient bone stock outside the United States Metabolic disorders which may impair bone formation Osteomalacia Distant foci of infections which may spread to implant site Rapid joint destruction, marked bone loss, or bone resorption apparent on roentgenogram Vascular insufficiency, muscular atrophy, neuromuscular disease. Incomplete or deficient soft tissue surrounding the knee. Charcot's disease A fixed varus deformity (not passively correctable) of greater than 15 degrees A flexion deformity greater than 15 degrees. Non-staged Bilateral patients Patients who refuse, cannot, or should not receive a CT or MRI. Since patients are randomized into treatment groups, all patients must be able to receive an MRI (should follow local MRI screening protocol). This excludes patients who have metal artifacts in the knee, patients who are too large to fit into the knee coil, patients with pacemakers, patients unable to lie still for the duration of the MRI, and patients who are claustrophobic.

Ages Eligible for Study
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Minimum Age: 21 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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Signature Custom Guides<br>Oxford Partial Knee implanted using Signature Custom Guides | Device: Signature Custom Guides<br>* Signature Custom Guides: Signature Custom Guides are intended to be used as a surgical instrument to assist in the positioning of knee replacement components intraoperatively and in guiding the marking of bone before cutting provided that anatomic landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans (preoperative MRI).<br>|
| Active Comparator: Conventional Instrumentation<br>Oxford Partial Knee implanted using Conventional Instrumentation | Procedure: Conventional Instrumentation<br>* Traditional partial knee arthroplasty without the use of Signature technology.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Knees Achieving Optimal Alignment | Percentage of Knees Achieving Optimal Alignment defined as a difference of 5 or less between all target and observed angles. | 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Instruments Used During Surgery | Number of Instrument cases used to complete index surgery. | Operative | 
| Knee Society Functional Score | Functional Score from Knee Society Score. These are 3 of the 10 items. Scored from 0 to 100 with lower scores being indicative of worse knee conditions and higher scores being indicative of better knee conditions | 1 Year | 
| Leg Alignment Femoral Varus/Valgus | Mechanical Leg Alignment of Components (degrees): Difference of Femoral Varus/Valgus angle as measured via CT-scan directly post-operative, vs target angle | Directly Postoperative | 
| Blood Loss | Blood Loss during surgery | Right after surgery (up to 2 hours after surgery) | 
| Knee Society Objective Score | Objective score from Knee Society Score. These are 7 of the 10 items. Scored from 0 to 100 with lower scores being indicative of worse knee conditions and higher scores being indicative of better knee conditions | 1 Year | 
| Oxford Knee Score | Oxford Knee Score (OKS). Scored from 0 to 48 with 0 being the worst possible outcome and 48 being the best outcome | 1 Year | 
| EQ5D Score | EuroQol 5D Quality of Life score. Range from 0 to 1 with 1 being the best outcome. | 1 Year | 
| Leg Alignment Femoral Flexion/Extension | Mechanical Leg Alignment of Components (degrees): Difference of Femoral Flexion/Extension angle as measured via CT-scan directly post-operative, vs target angle | Directly Postoperative | 
| Leg Alignment Tibial Varus/Valgus | Mechanical Leg Alignment of Components (degrees): Difference of Tibial Varus/Valgus angle as measured via CT-scan directly post-operative, vs target angle | Directly Postoperative | 
| Leg Alignment Tibial Flexion/Extension | Mechanical Leg Alignment of Components (degrees): Difference of Tibial Flexion/Extension angle as measured via CT-scan directly post-operative, vs target angle | Directly Postoperative | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Osteoarthritis, Osteoarthritis, Knee, Osteonecrosis, Arthritis, Knee Arthritis, Knee Replacement