Osteoarthritis, Knee
Conditions
Keywords
knee arthritis, total knee arthroplasty, total knee replacement, mobile bearing design, all-polyethylene tibia
Brief summary
This study will be designed to compare prospectively, in a randomized fashion, the clinical, functional, and radiographic results of a nonmodular (all-polyethylene tibi/AP) fixed-bearing posterior cruciate substituting design with a modular posterior cruciate substituting rotating platform (RP) design for total knee arthroplasty. Comparing these two designs will afford the investigators information in the following areas: 1. Does a RP design offer improvement in range of motion over a AP design? 2. Does a RP design have improved wear characteristics over a nonmodular AP design? 3. Is there a clear clinical advantage to the RP design that justifies its increased cost? Answering these questions will allow surgeons to use RP designs appropriately in different demand populations. This study was designed to address the questions of whether an RP design offers improvement in ROM, Knee Society scores, Western Ontario and McMaster Universities Index of Osteoarthritis (WOMAC) scores, selected Medical Outcomes Short-Form Health Survey Short Form-36 (SF-36) scores or radiographic measures, over an APT design. The investigators' primary hypothesis was that there would be no difference in these outcome measures at a minimum two year followup. A secondary hypothesis based on the anticipated long-term followup of this group was that there would be no difference in implant survival.
Interventions
PROCEDURETKA surgery with the rotating platform mobile-bearing knee design
Depuy Sigma RP rotating platform design
PROCEDURETKA surgery with the all-polyethylene tibia knee design
Depuy Sigma fixed-bearing design with all-polyethylene tibia
Sponsors
Depuy, Inc.
Minneapolis Veterans Affairs Medical Center
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
60 Years to 85 Years
Healthy volunteers
Yes
Inclusion criteria
* generally accepted clinical and radiographic criteria for primary total knee arthroplasty
Exclusion criteria
* substantial angular deformity or bony deformity requiring structural grafting or modular augmentation were excluded at the discretion of the principle investigator * patients whose mental function precluded them from responding to our standard questionnaires
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Knee Postoperative Range of Motion (ROM) at 2 Years | 2 years | range of motion of the knee postoperatively at 2 years |
Secondary
| Measure | Time frame |
|---|---|
| Survival of the Implants to Subject Death or Implant Removal | 10 or more years |
Countries
United States
Participant flow
Recruitment details
October 1, 2001 to January 1, 2007 recruitment period from the Minneapolis VAMC Orthopaedic Clinic
Pre-assignment details
Patients that were recruited but not enrolled either failed the inclusion criteria or elected not to participate
Participants by arm
| Arm | Count |
|---|---|
| Rotating-platform Design Total Knee Arthroplasty (TKA) patients who were randomized to receive the rotating platform mobile-bearing total knee arthroplasty (TKA) design | 200 |
| All-polyethylene Tibia Design Total Knee Arthroplasty (TKA) patients who were randomized to receive the all-polyethylene tibial component design | 200 |
| Total | 400 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | deaths and less than 2 years followup | 24 | 64 |
Baseline characteristics
| Characteristic | Rotating-platform Design Total Knee Arthroplasty (TKA) | All-polyethylene Tibia Design Total Knee Arthroplasty (TKA) | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 121 Participants | 126 Participants | 247 Participants |
| Age, Categorical Between 18 and 65 years | 79 Participants | 74 Participants | 153 Participants |
| range of motion of knee | 113.7 degrees STANDARD_DEVIATION 1 | 111.9 degrees STANDARD_DEVIATION 1.1 | 112.8 degrees STANDARD_DEVIATION 1.2 |
| Region of Enrollment United States | 200 participants | 200 participants | 400 participants |
| Sex: Female, Male Female | 5 Participants | 7 Participants | 12 Participants |
| Sex: Female, Male Male | 195 Participants | 193 Participants | 388 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 200 | 0 / 200 |
| serious Total, serious adverse events | 0 / 200 | 0 / 200 |
Outcome results
Primary
Knee Postoperative Range of Motion (ROM) at 2 Years
range of motion of the knee postoperatively at 2 years
Time frame: 2 years
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Rotating-platform Design Total Knee Arthroplasty (TKA) | Knee Postoperative Range of Motion (ROM) at 2 Years | 110.4 degrees | Standard Deviation 0.8 |
| All-polyethylene Tibia Design Total Knee Arthroplasty (TKA) | Knee Postoperative Range of Motion (ROM) at 2 Years | 111.9 degrees | Standard Deviation 0.9 |
Secondary
Survival of the Implants to Subject Death or Implant Removal
Time frame: 10 or more years
Population: PI/study coordinator retired due to personal family health matters and study sponsor withdrew funding. Study was terminated and no data was collected or analyzed from any participant for this outcome measure.