Vanguard™ Deep Dish Rotating Platform Knee Clinical Evaluation

Not Applicable

Completed

Conditions: Osteoarthritis

Interventions: Device: Vanguard™ Deep Dish Rotating Platform Knee
Device: Vanguard™ Cruciate Retaining Knee

Registration Number: NCT00753090

Lead Sponsor: Zimmer Biomet

Brief Summary: This study is being conducted on the Vanguard™ Deep Dish Rotating Platform (DD RP) to evaluate the clinical efficacy of the DDRP components.

Detailed Description: This study is designed to evaluate the safety and efficacy of Vanguard™ Deep Dish Rotating Platform Knee (mobile bearing knee) as compared to Vanguard Cruciate Retaining Knee (fixed bearing knee). This trial was conducted as the randomised, controlled study.

Implant loosening and polyethylene wear in fixed-bearing knee prostheses were recognized as major causes of late failure. The mobile bearing knee have the theoretical advantages of potentially minimizing the polyethylene wear and reducing implant to bone interface stress in order to reduce the incidence of implant loosening. Therefore, the aims of this study were to prove the Vanguard deep dish rotating platform knee is at least as effective in clinical outcome as the widely used current design of knee replacement and better in long term survivorship.

The efficacy of the device was determined by the relief of pain, restoration of function and range of motion. The durability of device was determined by the absence of revision/removal and radiological integrity. To assess the safety of the device, all post operative complications were recorded either device related or otherwise. Patient satisfaction was determined by answers to patient outcome questionnaires (Oxford Knee Score, WOMAC and Lower Extremity Activity Scale).

Between June 29, 2009 and March 5th 2012, 326 cases were enrolled in the study. In total 117 cases were implanted with the Vanguard fixed bearing cruciate retaining knee; the control arm, and 209 cases were implanted with the Vanguard DDRP. All of these patients fulfilled the inclusion/exclusion criteria. From the 4 participating sites, 2 of them (both located in the Netherlands, Zuyderland Hospital and Bravis Hospital) performed a randomized controlled trial (RCT). In the RCT, 40 cases were assigned to the Trial Arm (Vanguard DDRP), and 51 to the control arm (Vanguard CR). The UK site enrolled cases only in the Vanguard DDRP arm and the French site enrolled in both arms, but non-randomized. Total 326 patients are enrolled in the study.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 326

Inclusion Criteria

Patients with a pre-operative Knee Society Score of < 70
Patients scheduled to undergo primary total knee replacement with any of the following indication: Painful and disabled knee joint resulting from osteoarthritis, Traumatic Arthritis, Rheumatoid Arthritis; One or more compartments are involved
Need to obtain pain relief and improve function
Ability and willingness to follow instructions, including control of weight and activity level, and to return for follow-up evaluations
A good nutritional state of the patient
Full skeletal maturity of the patient, patients who are at least 18 years of age
Patients of either sex
Consent form read, understood, and signed by patient

Exclusion Criteria

Absolute contraindications include the following diagnoses:

Patients with a pre-operative Knee Society Score of >= 70
Infection
Osteomyelitis
Previous partial or total prosthetic knee replacement on the operative side
Patients who are less than 18 years of age
Sepsis
Patients who had body mass index >= 40

Relative contraindications include the following factors:

Uncooperative patient or patient with neurological disorders who are incapable of following directions or who are predictably unwilling to return for follow-up examinations
Osteoporosis or marked bone loss, which may preclude proper fixation of the prosthesis
Metabolic disorders, which may impair bone formation
Osteomalacia
Distant foci of infections, which may spread to the implant site
Rapid joint destruction, marked bone loss, or bone resorption apparent on roentgenogram
Vascular insufficiency, muscular atrophy, or neuromuscular disease in the affected limb.
Incomplete or deficient soft tissue surrounding the knee

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
VG DDRP	Vanguard™ Deep Dish Rotating Platform Knee	This arm utilizes the Vanguard™ Deep Dish Rotating Platform Knee.
VG CR	Vanguard™ Cruciate Retaining Knee	This arm utilizes the Vanguard™ Cruciate Retaining Knee.

Primary Outcome Measures

Name	Time	Method
Knee Society Score	2 years	The Knee Society Score (KSS) is a clinician-completed questionnaire and consists of two sub-scores: an Objective score assessing pain, range of motion, anteroposterior and mediolateral stability, along with deductions for higher than normal flexion contracture, extension lag and/or varus/valgus alignment, and a Function score, assessing walking on level ground and walking up and down stairs, along with deductions for support. Each sub-score can range from 0 to 100 points, with higher scores corresponding to better outcomes, classified as Excellent: 80 - 100 points; Good: 70 - 79 points; Fair: 60 - 69 points; Poor: \< 60 points.

Secondary Outcome Measures

Name	Time	Method
Survivorship	10 years	implant survival at 10 years post surgery and is presented by the number of cases with the implants unrevised
Knee Society Score	6 weeks, 6 months, annually until all available study patients have completed two-year follow up evaluation and alternating odd years or as needed thereafter up to 10 years	The Knee Society Score (KSS) is a clinician-completed questionnaire and consists of two sub-scores: an Objective score assessing pain, range of motion, anteroposterior and mediolateral stability, along with deductions for higher than normal flexion contracture, extension lag and/or varus/valgus alignment, and a Function score, assessing walking on level ground and walking up and down stairs, along with deductions for support. Each sub-score can range from 0 to 100 points, with higher scores corresponding to better outcomes, classified as Excellent: 80 - 100 points; Good: 70 - 79 points; Fair: 60 - 69 points; Poor: \< 60 points.
Radiographic Evaluation: Total Varus Angle	6 weeks, 6 months, 1, 2, 3, 5, 7, and 10 years postoperative	Assessment of patient x-rays by each site investigator: Total varus angle. This is defined as the sum of the femoral flexion (the angle between the femoral median axis and the tibial median axis) and the tibial angle (the angle between the anatomical axis of the femur and the tibia in the anteroposterior view of the knee joint) minus 180 degrees.
Radiographic Evaluation: Radiolucency	6 weeks, 6 months, 1, 2, 3, 5, 7 and 10 years postoperative	Assessment of patient x-rays by each site investigator: Radiolucency Femoral Radiolucency is defined as the total nr of participants with radiolucency measured on the femur in each of the 7 different zones. Tibia AP Radiolucency is defined as total nr of participants with radiolucency in each of the 7 zones measured in the AP view X-ray Tibia lateral Radiolucency defined as total nr of participants with radiolucency in each of the 3 zones in the lateral view X-ray Patella Radiolucency is defined as total nr of participants with radiolucency in each of the 5 zones

Trial Locations

Locations (4): CHU Lyon Sud
🇫🇷
Pierre Benite, France
The Hillingdon Hospital NHS Trust
🇬🇧
Middlesex, United Kingdom
Zuyderland Medisch Centrum Sittard-Geleen
🇳🇱
Sittard, Netherlands
Bravis Ziekenhuis
🇳🇱
Roosendaal, Netherlands