Trial Outcomes & Findings for X-3 Polyethylene Survival Outcomes Study (NCT NCT00493792)
NCT ID: NCT00493792
Last Updated: 2024-11-06
Results Overview
The survival of prostheses free of revision 10 years post operation.
COMPLETED
NA
518 participants
From operation to 10 years post-operative
2024-11-06
Participant Flow
Patients were recruited at the following sites: Mayo Clinic in Rochester, MN, Mayo Clinic in Florida, and Mayo Clinic in Arizona. Patients, who met study criteria, planning to undergo a total knee replacement were offered study participation at their pre-operative visit.
Participant milestones
| Measure |
Control
Stryker Orthopaedics N2Vac Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
N2Vac Polyethylene: Ultra-high-molecular-weight polyethylene (UHMWPE).
|
Treatment
X3 Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
Stryker X3 Crosslink Polyethylene: Highly cross-linked polyethylene (HXLPE).
|
|---|---|---|
|
Overall Study
STARTED
|
254
|
264
|
|
Overall Study
Year 2
|
245
|
256
|
|
Overall Study
Year 5
|
233
|
241
|
|
Overall Study
Year 7
|
207
|
211
|
|
Overall Study
COMPLETED
|
163
|
163
|
|
Overall Study
NOT COMPLETED
|
91
|
101
|
Reasons for withdrawal
| Measure |
Control
Stryker Orthopaedics N2Vac Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
N2Vac Polyethylene: Ultra-high-molecular-weight polyethylene (UHMWPE).
|
Treatment
X3 Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
Stryker X3 Crosslink Polyethylene: Highly cross-linked polyethylene (HXLPE).
|
|---|---|---|
|
Overall Study
Death
|
55
|
50
|
|
Overall Study
Lost to Follow Up or Lack of Efficacy
|
36
|
51
|
Baseline Characteristics
Race and Ethnicity were not collected from any participant.
Baseline characteristics by cohort
| Measure |
Control
n=254 Participants
Stryker Orthopaedics N2Vac Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
N2Vac Polyethylene: Ultra-high-molecular-weight polyethylene (UHMWPE).
|
Treatment
n=264 Participants
X3 Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
Stryker X3 Crosslink Polyethylene: Highly cross-linked polyethylene (HXLPE).
|
Total
n=518 Participants
Total of all reporting groups
|
|---|---|---|---|
|
Age, Continuous
|
67 years
STANDARD_DEVIATION 9 • n=254 Participants
|
67 years
STANDARD_DEVIATION 9 • n=264 Participants
|
67 years
STANDARD_DEVIATION 9 • n=518 Participants
|
|
Sex: Female, Male
Female
|
145 Participants
n=254 Participants
|
155 Participants
n=264 Participants
|
300 Participants
n=518 Participants
|
|
Sex: Female, Male
Male
|
109 Participants
n=254 Participants
|
109 Participants
n=264 Participants
|
218 Participants
n=518 Participants
|
|
Race and Ethnicity Not Collected
|
—
|
—
|
0 Participants
Race and Ethnicity were not collected from any participant.
|
|
Height (cm)
|
169 centimeters
STANDARD_DEVIATION 10 • n=254 Participants
|
169 centimeters
STANDARD_DEVIATION 10 • n=264 Participants
|
169 centimeters
STANDARD_DEVIATION 10 • n=518 Participants
|
|
Weight (kg)
|
92 kilograms
STANDARD_DEVIATION 21 • n=254 Participants
|
92 kilograms
STANDARD_DEVIATION 21 • n=264 Participants
|
92 kilograms
STANDARD_DEVIATION 21 • n=518 Participants
|
|
BMI, kg/m^2
|
32 Kilogram-Square Meter (kg/m^2)
STANDARD_DEVIATION 7 • n=254 Participants
|
32 Kilogram-Square Meter (kg/m^2)
STANDARD_DEVIATION 6 • n=264 Participants
|
32 Kilogram-Square Meter (kg/m^2)
STANDARD_DEVIATION 7 • n=518 Participants
|
|
Previous knee surgery, n (%)
Yes, previous knee surgery
|
91 Participants
n=254 Participants
|
82 Participants
n=264 Participants
|
173 Participants
n=518 Participants
|
|
Previous knee surgery, n (%)
No, previous knee surgery
|
157 Participants
n=254 Participants
|
179 Participants
n=264 Participants
|
336 Participants
n=518 Participants
|
|
Previous knee surgery, n (%)
Unknown
|
6 Participants
n=254 Participants
|
3 Participants
n=264 Participants
|
9 Participants
n=518 Participants
|
PRIMARY outcome
Timeframe: From operation to 10 years post-operativePopulation: Patients were recruited from three academic, tertiary-care referral centers within one healthcare network. Patients approached for enrollment received a primary unilateral total knee arthroplasty (TKA) for a diagnosis of osteoarthritis (OA), avascular necrosis (AVN) or posttraumatic arthritis.
The survival of prostheses free of revision 10 years post operation.
Outcome measures
| Measure |
Control
n=254 Participants
Stryker Orthopaedics N2Vac Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
N2Vac Polyethylene: Ultra-high-molecular-weight polyethylene (UHMWPE).
|
Treatment
n=264 Participants
Stryker Orthopaedics X3 Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
X3 Crosslink Polyethylene: Highly cross-linked polyethylene (HXLPE).
|
|---|---|---|
|
Prosthesis Survivorship Free of Revision
|
96 percentage of prosthesis survivorship
Interval 93.0 to 98.0
|
97 percentage of prosthesis survivorship
Interval 94.0 to 99.0
|
SECONDARY outcome
Timeframe: From operation to 10 years post-operativePopulation: Patients were recruited from three academic, tertiary-care referral centers within one healthcare network. Patients approached for enrollment received a primary unilateral total knee arthroplasty (TKA) for a diagnosis of osteoarthritis (OA), avascular necrosis (AVN) or posttraumatic arthritis.
The survival of prostheses free of reoperation 10 years post operation.
Outcome measures
| Measure |
Control
n=254 Participants
Stryker Orthopaedics N2Vac Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
N2Vac Polyethylene: Ultra-high-molecular-weight polyethylene (UHMWPE).
|
Treatment
n=264 Participants
Stryker Orthopaedics X3 Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
X3 Crosslink Polyethylene: Highly cross-linked polyethylene (HXLPE).
|
|---|---|---|
|
Prosthesis Survivorship Free of Reoperation
|
92 percentage of prosthesis survivorship
Interval 89.0 to 96.0
|
96 percentage of prosthesis survivorship
Interval 93.0 to 99.0
|
SECONDARY outcome
Timeframe: From operation to 10 years post-operativePopulation: Patients were recruited from three academic, tertiary-care referral centers within one healthcare network. Patients approached for enrollment received a primary unilateral total knee arthroplasty (TKA) for a diagnosis of osteoarthritis (OA), avascular necrosis (AVN) or posttraumatic arthritis.
The survival of prostheses free of related complications (non-operative) 10 years post operation.
Outcome measures
| Measure |
Control
n=254 Participants
Stryker Orthopaedics N2Vac Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
N2Vac Polyethylene: Ultra-high-molecular-weight polyethylene (UHMWPE).
|
Treatment
n=264 Participants
Stryker Orthopaedics X3 Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
X3 Crosslink Polyethylene: Highly cross-linked polyethylene (HXLPE).
|
|---|---|---|
|
Prosthesis Survivorship Free of Complications
|
84.9 percentage of prosthesis survivorship
Interval 80.2 to 89.5
|
88.8 percentage of prosthesis survivorship
Interval 84.5 to 92.8
|
SECONDARY outcome
Timeframe: Pre-operative (baseline) and 10-years post-operativePopulation: Patients who completed the Knee Society Score at baseline and patients who completed the Knee Society Score at 10-years post-operation. Data was not collected nor analyzed for 90 patients in the control arm, and 93 patients in the treatment arm at the 10 year follow-up.
The KSS evaluates pain, stability and range of motion. The scale ranges between scores of 0-100. The maximum score of 100 points is reached when there is no pain, with good alignment of the knee in extension, and at least 125° of range of motion, without any anteroposterior or mediolateral instability. Deductions are made for flexion contracture, loss of extension and poor alignment. Higher scores indicate better knee conditions, while lower scores indicate worse knee conditions.
Outcome measures
| Measure |
Control
n=123 Participants
Stryker Orthopaedics N2Vac Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
N2Vac Polyethylene: Ultra-high-molecular-weight polyethylene (UHMWPE).
|
Treatment
n=121 Participants
Stryker Orthopaedics X3 Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
X3 Crosslink Polyethylene: Highly cross-linked polyethylene (HXLPE).
|
|---|---|---|
|
Knee Society Score (KSS)
Baseline Score
|
39.9 score on a scale
Standard Deviation 14.19
|
39.0 score on a scale
Standard Deviation 12.56
|
|
Knee Society Score (KSS)
10-Year Follow-Up Score
|
77.6 score on a scale
Standard Deviation 8.60
|
76.5 score on a scale
Standard Deviation 6.32
|
SECONDARY outcome
Timeframe: Pre-operative (baseline) and 10-years post-operativePopulation: Patients who completed the Knee Society Function Score at baseline and patients who completed the Knee Society Function Score at 10-years post-operation. Data was not collected nor analyzed for 62 patients in the control arm, and 47 patients in the treatment arm at the 10 year follow-up.
The Function KSS evaluates the walking distance and the act of climbing and descending stairs. The scale ranges between 0-100. The maximum score of 100 points is attributed to the individual capable of walking unlimited distances without walking aids, and of climbing and descending stairs normally. Deductions are made for the use of canes, crutches or walking frame. Higher scores indicate better knee conditions, while lower scores indicate worse knee conditions.
Outcome measures
| Measure |
Control
n=156 Participants
Stryker Orthopaedics N2Vac Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
N2Vac Polyethylene: Ultra-high-molecular-weight polyethylene (UHMWPE).
|
Treatment
n=159 Participants
Stryker Orthopaedics X3 Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
X3 Crosslink Polyethylene: Highly cross-linked polyethylene (HXLPE).
|
|---|---|---|
|
Knee Society Score (KSS): Function
Baseline Score
|
58.3 score on a scale
Standard Deviation 17.38
|
59.1 score on a scale
Standard Deviation 15.48
|
|
Knee Society Score (KSS): Function
10-Year Follow-Up Score
|
70.2 score on a scale
Standard Deviation 26.25
|
70.3 score on a scale
Standard Deviation 26.16
|
SECONDARY outcome
Timeframe: Pre-operative (baseline) and 10-years post-operativePopulation: Patients who completed the SF-12 Mental Health Score at baseline and patients who completed the SF-12 Mental Health Score at 10-years post-operation. Data was not collected nor analyzed for 187 patients in the control arm, and 193 patients in the treatment arm at the 10 year follow-up.
The SF-12 questionnaire uses questions selected from the longer SF-36 Health Survey to measure patient wellness and quality of life. The scoring algorithm is calibrated so that an average healthy person would have a t-score of 50 points with a standard deviation of 10. Higher scores indicate better mental health.
Outcome measures
| Measure |
Control
n=228 Participants
Stryker Orthopaedics N2Vac Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
N2Vac Polyethylene: Ultra-high-molecular-weight polyethylene (UHMWPE).
|
Treatment
n=233 Participants
Stryker Orthopaedics X3 Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
X3 Crosslink Polyethylene: Highly cross-linked polyethylene (HXLPE).
|
|---|---|---|
|
12-Item Short Form Health Survey (SF-12): Mental Health Score
Baseline Score
|
56 score on a scale
Standard Deviation 9.64
|
56.2 score on a scale
Standard Deviation 8.89
|
|
12-Item Short Form Health Survey (SF-12): Mental Health Score
10-Year Follow-Up Score
|
56.8 score on a scale
Standard Deviation 6
|
56.3 score on a scale
Standard Deviation 7.65
|
SECONDARY outcome
Timeframe: Pre-operative (baseline) and 10-years post-operativePopulation: Patients who completed the SF-12 Physical Health Score at baseline and patients who completed the SF-12 Physical Health Score at 10-years post-operation. Data was not collected nor analyzed for 187 patients in the control arm, and 193 patients in the treatment arm at the 10 year follow-up.
The SF-12 questionnaire uses questions selected from the longer SF-36 Health Survey to measure patient wellness and quality of life. The scoring algorithm is calibrated so that an average healthy person would have a t-score of 50 points with a standard deviation of 10. Higher scores indicate better physical health.
Outcome measures
| Measure |
Control
n=228 Participants
Stryker Orthopaedics N2Vac Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
N2Vac Polyethylene: Ultra-high-molecular-weight polyethylene (UHMWPE).
|
Treatment
n=233 Participants
Stryker Orthopaedics X3 Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
X3 Crosslink Polyethylene: Highly cross-linked polyethylene (HXLPE).
|
|---|---|---|
|
12-Item Short Form Health Survey (SF-12): Physical Health Score
Baseline Score
|
32.5 score on a scale
Standard Deviation 8.34
|
33.2 score on a scale
Standard Deviation 8.59
|
|
12-Item Short Form Health Survey (SF-12): Physical Health Score
10-Year Follow-Up Score
|
41.9 score on a scale
Standard Deviation 11.28
|
44.4 score on a scale
Standard Deviation 10.37
|
SECONDARY outcome
Timeframe: 10 years post-operativePopulation: Patients who completed 10-year post-operation radiographs of the study-related prosthetic joint.
Radiographic review for success and or failure of the TKA prostheses at 10 years post-operation. A migrating or shifting prosthesis with or without the disappearance of radiolucent lines is considered a failure.
Outcome measures
| Measure |
Control
n=40 Participants
Stryker Orthopaedics N2Vac Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
N2Vac Polyethylene: Ultra-high-molecular-weight polyethylene (UHMWPE).
|
Treatment
n=23 Participants
Stryker Orthopaedics X3 Polyethylene when used with a Triathlon Posterior Stabilized total knee system. This is a fixed- bearing knee intended for use in patients undergoing cemented total knee arthroplasty.
X3 Crosslink Polyethylene: Highly cross-linked polyethylene (HXLPE).
|
|---|---|---|
|
Comparison of Radiographic Success/Failure Between Groups
Loosening and/or Osteolysis
|
0 Participants
|
0 Participants
|
|
Comparison of Radiographic Success/Failure Between Groups
Tibial component bone-cement interface: Non-progressive radiolucent lines
|
7 Participants
|
2 Participants
|
|
Comparison of Radiographic Success/Failure Between Groups
Femoral component bone-prosthesis interface: Radiolucent lines
|
3 Participants
|
0 Participants
|
Adverse Events
Control
Treatment
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Emilee Andersen, M.A., Clinical Research Coordinator
Mayo Clinic, Rochester, MN
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place