Trial Outcomes & Findings for Total Knee Arthroplasty With Vitamin E Polyethylene (NCT NCT05810285)
NCT ID: NCT05810285
Last Updated: 2025-01-03
Results Overview
Kaplan-Meier cumulative survival with revision due to aseptic loosening as the end-point
Recruitment status
COMPLETED
Target enrollment
186 participants
Primary outcome timeframe
10-year follow-up
Results posted on
2025-01-03
Participant Flow
During recruitment process, 350 total knee arthroplasties (181 with vitamin E polyethylene and 169 with conventional polyethylene) were identified as eligible. Overall 151 total knee arthroplasties were lost to follow-up and were not enrolled (79 with vitamin E polyethylene and 72 with conventional polyethylene). 186 participants (199 knees) were enrolled.
186 participants (199 knees) were enrolled in the study and were assigned to each arm
Unit of analysis: Knees (knee implants)
Participant milestones
| Measure |
VITAMIN E
Cemented total knee arthroplasty with vitamin E blended polyethylene mobile bearing and GKS Prime Flex Mobile knee
|
POLYETHYLENE
Cemented total knee arthroplasty with conventional polyethylene mobile bearing and GKS Prime Flex Mobile knee
|
|---|---|---|
|
Overall Study
STARTED
|
95 102
|
91 97
|
|
Overall Study
COMPLETED
|
73 80
|
54 60
|
|
Overall Study
NOT COMPLETED
|
22 22
|
37 37
|
Reasons for withdrawal
| Measure |
VITAMIN E
Cemented total knee arthroplasty with vitamin E blended polyethylene mobile bearing and GKS Prime Flex Mobile knee
|
POLYETHYLENE
Cemented total knee arthroplasty with conventional polyethylene mobile bearing and GKS Prime Flex Mobile knee
|
|---|---|---|
|
Overall Study
Death
|
4
|
21
|
|
Overall Study
Adverse Event
|
18
|
16
|
Baseline Characteristics
Race and Ethnicity were not collected from any participant.
Baseline characteristics by cohort
| Measure |
VITAMIN E
n=102 Knees (Knee implants)
Patients who received cemented total knee arthroplasty with vitamin E blended polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
POLYETHYLENE
n=97 Knees (Knee implants)
Patients who received cemented total knee arthroplasty with conventional polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
Total
n=199 Knees (Knee implants)
Total of all reporting groups
|
|---|---|---|---|
|
Age, Continuous
|
65.3 years
STANDARD_DEVIATION 6.7 • n=102 Knees (Knee implants)
|
75.3 years
STANDARD_DEVIATION 5.7 • n=97 Knees (Knee implants)
|
70.1 years
STANDARD_DEVIATION 7.9 • n=199 Knees (Knee implants)
|
|
Sex: Female, Male
Female
|
61 Knees (Knee implants)
n=102 Knees (Knee implants)
|
80 Knees (Knee implants)
n=97 Knees (Knee implants)
|
141 Knees (Knee implants)
n=199 Knees (Knee implants)
|
|
Sex: Female, Male
Male
|
41 Knees (Knee implants)
n=102 Knees (Knee implants)
|
17 Knees (Knee implants)
n=97 Knees (Knee implants)
|
58 Knees (Knee implants)
n=199 Knees (Knee implants)
|
|
Race and Ethnicity Not Collected
|
—
|
—
|
0 Participants
Race and Ethnicity were not collected from any participant.
|
|
Follow-up
|
8.5 years
STANDARD_DEVIATION 2.1 • n=102 Knees (Knee implants)
|
8.3 years
STANDARD_DEVIATION 2.2 • n=97 Knees (Knee implants)
|
8.4 years
STANDARD_DEVIATION 2.1 • n=199 Knees (Knee implants)
|
|
Diagnosis
Osteoarthritis
|
98 Knees (Knee implants)
n=102 Knees (Knee implants)
|
96 Knees (Knee implants)
n=97 Knees (Knee implants)
|
194 Knees (Knee implants)
n=199 Knees (Knee implants)
|
|
Diagnosis
Rheumatoid arthritis
|
2 Knees (Knee implants)
n=102 Knees (Knee implants)
|
0 Knees (Knee implants)
n=97 Knees (Knee implants)
|
2 Knees (Knee implants)
n=199 Knees (Knee implants)
|
|
Diagnosis
Post-traumatic osteoarthritis
|
2 Knees (Knee implants)
n=102 Knees (Knee implants)
|
1 Knees (Knee implants)
n=97 Knees (Knee implants)
|
3 Knees (Knee implants)
n=199 Knees (Knee implants)
|
|
BMI
|
29.9 kg/m^2
STANDARD_DEVIATION 5.9 • n=102 Knees (Knee implants)
|
27.8 kg/m^2
STANDARD_DEVIATION 5.1 • n=97 Knees (Knee implants)
|
29.0 kg/m^2
STANDARD_DEVIATION 5.6 • n=199 Knees (Knee implants)
|
PRIMARY outcome
Timeframe: 10-year follow-upKaplan-Meier cumulative survival with revision due to aseptic loosening as the end-point
Outcome measures
| Measure |
VITAMIN E
n=102 Knees (knee implants)
Patients who received cemented total knee arthroplasty with vitamin E blended polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
POLYETHYLENE
n=97 Knees (knee implants)
Patients who received cemented total knee arthroplasty with conventional polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
|---|---|---|
|
Implant Survival for Aseptic Loosening
|
95.0 percentage of survival implants
Interval 88.5 to 97.8
|
97.8 percentage of survival implants
Interval 91.6 to 99.4
|
SECONDARY outcome
Timeframe: 10-year follow-upKaplan-Meier cumulative survival with revision due to any reason as the end-point
Outcome measures
| Measure |
VITAMIN E
n=102 Knees (knee implants)
Patients who received cemented total knee arthroplasty with vitamin E blended polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
POLYETHYLENE
n=97 Knees (knee implants)
Patients who received cemented total knee arthroplasty with conventional polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
|---|---|---|
|
Implant Survival for Any Reason
|
87.6 percentage of survival implants
Interval 75.8 to 93.8
|
89.6 percentage of survival implants
Interval 81.6 to 94.2
|
SECONDARY outcome
Timeframe: At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectivelyPopulation: Number of knees of patients who was contacted by phone or who returned back to hospital for clinical examination follow-up
Patient related outcome measurement scored from 0 to 100 (higher scores mean better outcomes)
Outcome measures
| Measure |
VITAMIN E
n=80 Knees (knee implants)
Patients who received cemented total knee arthroplasty with vitamin E blended polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
POLYETHYLENE
n=60 Knees (knee implants)
Patients who received cemented total knee arthroplasty with conventional polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
|---|---|---|
|
Forgotten Joint Score (FJS-12)
|
59 score on a scale
Standard Deviation 30
|
56 score on a scale
Standard Deviation 27
|
SECONDARY outcome
Timeframe: At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectivelyPopulation: Knees of patients who returned back to the hospital for complete clinical and radiographic follow-up
Clinical and Functional scores of the knee. Both scores are scored from 0 to 100 (higher scores mean better outcomes)
Outcome measures
| Measure |
VITAMIN E
n=52 Knees (knee implants)
Patients who received cemented total knee arthroplasty with vitamin E blended polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
POLYETHYLENE
n=31 Knees (knee implants)
Patients who received cemented total knee arthroplasty with conventional polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
|---|---|---|
|
American Knee Society Score (KSS)
KSS - Knee score
|
84 score on a scale
Standard Deviation 16
|
80 score on a scale
Standard Deviation 16
|
|
American Knee Society Score (KSS)
KSS - Function score
|
77 score on a scale
Standard Deviation 26
|
63 score on a scale
Standard Deviation 31
|
SECONDARY outcome
Timeframe: At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectivelyPopulation: Knees of patients who returned back to hospital for clinical and radiographic follow-up.
Radiographic sign of bone remodelling around the implant
Outcome measures
| Measure |
VITAMIN E
n=52 Knees (knee implants)
Patients who received cemented total knee arthroplasty with vitamin E blended polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
POLYETHYLENE
n=31 Knees (knee implants)
Patients who received cemented total knee arthroplasty with conventional polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
|---|---|---|
|
Periprosthetic Radiolucent Line
|
28 Knees (knee implants)
|
10 Knees (knee implants)
|
SECONDARY outcome
Timeframe: At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectivelyPopulation: Knees of patients who returned back to hospital for clinical and radiographic follow-up
Radiographic sign of focal bone resorption around the implant
Outcome measures
| Measure |
VITAMIN E
n=52 Knees (knee implants)
Patients who received cemented total knee arthroplasty with vitamin E blended polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
POLYETHYLENE
n=31 Knees (knee implants)
Patients who received cemented total knee arthroplasty with conventional polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
|---|---|---|
|
Periprosthetic Osteolysis
|
1 Knees (knee implants)
|
1 Knees (knee implants)
|
Adverse Events
VITAMIN E
Serious events: 18 serious events
Other events: 22 other events
Deaths: 4 deaths
POLYETHYLENE
Serious events: 16 serious events
Other events: 14 other events
Deaths: 21 deaths
Serious adverse events
| Measure |
VITAMIN E
n=102 participants at risk
Patients who received cemented total knee arthroplasty with vitamin E blended polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
POLYETHYLENE
n=97 participants at risk
Patients who received cemented total knee arthroplasty with conventional polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
|---|---|---|
|
Musculoskeletal and connective tissue disorders
Revision for aseptic loosening
|
4.9%
5/102 • Number of events 5 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
2.1%
2/97 • Number of events 2 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
|
Musculoskeletal and connective tissue disorders
Revision for any reason other than aseptic loosening
|
4.9%
5/102 • Number of events 5 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
8.2%
8/97 • Number of events 8 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
|
Musculoskeletal and connective tissue disorders
Reintervention for patella resurfacing
|
3.9%
4/102 • Number of events 4 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
2.1%
2/97 • Number of events 2 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
|
Musculoskeletal and connective tissue disorders
Reintervention for other reason than patella resurfacing
|
2.9%
3/102 • Number of events 3 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
3.1%
3/97 • Number of events 3 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
|
Cardiac disorders
Deep venous thrombosis
|
0.98%
1/102 • Number of events 1 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
0.00%
0/97 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
|
Cardiac disorders
Ventricular tachycardis
|
0.00%
0/102 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
1.0%
1/97 • Number of events 1 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
Other adverse events
| Measure |
VITAMIN E
n=102 participants at risk
Patients who received cemented total knee arthroplasty with vitamin E blended polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
POLYETHYLENE
n=97 participants at risk
Patients who received cemented total knee arthroplasty with conventional polyethylene mobile bearing
GKS Prime Flex Mobile knee: Total knee arthroplasty with a cemented mobile bearing bicompartmental knee prosthesis
|
|---|---|---|
|
Musculoskeletal and connective tissue disorders
Stiffness
|
14.7%
15/102 • Number of events 15 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
4.1%
4/97 • Number of events 4 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
|
Musculoskeletal and connective tissue disorders
Painfull knee
|
5.9%
6/102 • Number of events 6 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
6.2%
6/97 • Number of events 6 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
|
Musculoskeletal and connective tissue disorders
Intraoperative bone fracture
|
0.98%
1/102 • Number of events 1 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
1.0%
1/97 • Number of events 1 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
|
Infections and infestations
Delayed wound healing
|
0.00%
0/102 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
2.1%
2/97 • Number of events 2 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
|
Musculoskeletal and connective tissue disorders
Instability
|
0.00%
0/102 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
1.0%
1/97 • Number of events 1 • At mean follow-up of 8.5 years and 8.3 years for Vitamin E and Polyethylene, respectively
Surgical implant revision with prosthetic component replacement and surgical reintervention fall within the Serious adverse events definition
|
Additional Information
Lorenzo Banci, study coordinator - clinical affairs
Permedicaspa
Phone: 0399514811
Email: [email protected]
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place