Joint Disease, Osteoarthritis, Osteoarthritis, Knee
Conditions
Brief summary
The study is a prospective, randomized comparison of total knee arthroplasty with the Medacta GMK Sphere® knee compared to the Medacta GMK PS knee, with comparison to data from previous trials of similar study design.
Detailed description
There is no consensus within the Arthroplasty community as to whether a traditional post and cam-style PS total knee device is superior to a medial-pivot, more congruent device. However, the majority of surgeons seem to prefer the former, though there is a minority that uses the latter device with great success. To date, there have been few prospective trials directly comparing these devices, and none with the latest generation of TKA implants. Almost all such studies have been retrospective, and/or non-randomized, and/or utilizing older generation devices. The primary objective of this study is to compare the average Forgotten Knee Score (FJS) of those patients receiving the Medacta GMK Sphere knee with the average FJS of those receiving the Medacta GMK PS knee at the two and five year time points. It is expected that those subjects implanted with the Medacta GMK Sphere knee will show significantly better Forgotten Joint Scores at two and five year follow-up when compared with those receiving the Medacta GMK PS knee. The FJS was not collected in the prior comparison studies, and so cannot be evaluated across the knee systems.
Interventions
DEVICEMedacta GMK Sphere® Medial-Pivot Knee Prosthesis
DEVICEMedacta GMK PS Posterior Stabilized Knee Prosthesis
Sponsors
David F. Scott, MD
Medacta USA
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
21 Years to 80 Years
Healthy volunteers
Yes
Inclusion criteria
* Patients willing to sign the Informed Consent. * Patients able to comply with follow-up requirements including postoperative weight bearing restrictions and self-evaluations. * Male and non-pregnant female patients ages 21 - 80 years of age at the time of surgery. * Patients requiring a primary total knee replacement. * Patients with a diagnosis of osteoarthritis (OA), traumatic arthritis (TA), or avascular necrosis (AVN). * Patients with intact collateral ligaments.
Exclusion criteria
* Patients with inflammatory arthritis. * Patients that are morbidly obese, body mass index (BMI) \> 40. * Patients with a history of total or unicompartmental reconstruction of the affected joint. * Patients with neuromuscular or neurosensory deficiency, which would limit the ability to assess the performance of the device. * Patients with a systemic or metabolic disorder leading to progressive bone deterioration. * Patients that are immunologically compromised, or receiving chronic steroids (\>30 days), excluding inhalers. * Patients bone stock is compromised by disease or infection, which cannot provide adequate support and/or fixation to the prosthesis. * Patients with knee fusion to the affected joint. * Patients with an active or suspected latent infection in or about the knee joint. * Patients whose surgery will utilize computer-assisted surgical navigation (CAOS) techniques. * Patients whose surgery will utilize minimally invasive surgical techniques. * Patients that are prisoners.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Forgotten Joint Score (FJS) | Change from baseline at 2 years and 5 years post-operative | The average Forgotten Joint Score (FJS) of those patients receiving the Medacta GMK Sphere® knee prosthesis will be compared with the average FJS of those receiving the Medacta GMK PS knee prosthesis. The FJS total score range is 0-100, with higher scores indicating a higher degree of "forgetting" the artificial joint, that is, a lower degree of awareness. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Total Knee Society Score (KSS) | Pre-operative, 6 weeks, 6 months, 1, 2, 3, 4, and 5 years post-operative | Clinical outcomes will be evaluated via the Knee Society Score (KSS). The KSS is subdivided into a Knee Assessment score which rates only the knee joint itself, and a Functional Assessment score which rates the subject's ability to walk and climb stairs. Both scores range from 0-100, with a higher score indicating a better outcome. |
| Lower Extremity Activity Scale (LEAS) | Pre-operative, 6 weeks, 6 months, 1, 2, 3, 4, and 5 years post-operative | Clinical outcomes will be evaluated via the Lower Extremity Activity Scale (LEAS). The LEAS scale range is 1-18, with a higher value indicating a higher level of activity. |
| Radiographic Analysis | Pre-operative, 6 weeks, 6 months, 1, 2, 3, 4, and 5 years post-operative | Radiographs will be assessed for radiolucency, migration and subsidence. An AP Longstanding view will be obtained pre-operatively, and at 6 weeks and 1 year post-operatively to determine degree of Varus or Valgus. |
Countries
United States
Contacts
PRINCIPAL_INVESTIGATORDavid Scott, MD
Spokane Joint Replacement Center
Outcome results
None listed