Knee Osteoarthritis
Conditions
Keywords
total knee replacement, high flexion, range of motion, rotating platform, TKA
Brief summary
The goal of this study is to determine if the rotating platform high flex design provides improved flexion compared to the standard rotating platform TKA.
Interventions
DEVICERotating Platform High-Flex Cruciate Substituting TKA
DEVICERotating Platform Cruciate Substituting TKA
Sponsors
DePuy Orthopaedics
Anderson Orthopaedic Research Institute
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
40 Years to 75 Years
Healthy volunteers
No
Inclusion criteria
* Age 40 to 75 years old * Primary diagnosis of osteoarthritis of the knee * Patients who, in the investigator's opinion, are appropriate candidates for a cemented, rotating platform TKA. * Patients who, in the investigator's opinion, are capable of participation in a clinical trial and reliable enough to return for follow-up appointments.
Exclusion criteria
* Pregnant or lactating female subjects * Patients with post-traumatic or inflammatory arthritis * Patients with a fixed flexion contracture of greater than 20 degrees * Patients with advanced hip, spine, or ankle disease * Patients with a BMI greater than 40, where knee flexion may be limited by soft tissues
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Clinical Flexion | Preoperative, 4-6 weeks | Maximum, passive flexion and extension of the operated knee joint in the supine position will be measured and recorded using a long goniometer. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Radiographic Flexion | preoperative, 4-6 weeks | Lateral radiographs of the knee will be taken with the patient supine with maximal passive knee flexion. Flexion will then be measured directly from these radiographs. |
| Knee Society Score (KSS) | 1 year | A standard clinical evaluation system for reporting results for patients undergoing total knee replacement. The minimum score is 0 and the highest score is 100. A higher score represents a better outcome. |
| Oxford Knee Score | 1 year | A patient reported questionnaire for assessing the outcome of knee surgery. The minimum score is 0 and the maximum score is 48. A higher score represents a better outcome. |
Participant flow
Recruitment details
Subject enrollment began August 2007 and ended April 2009, with a total of 142 patients enrolled at an orthopaedic clinic.
Participants by arm
| Arm | Count |
|---|---|
| Rotating Platform High-Flex Cruciate Substituting TKA | 71 |
| Rotating Platform Cruciate Substituting TKA | 71 |
| Total | 142 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Adverse Event | 1 | 1 |
| Overall Study | Has not scheduled one-year visit yet | 2 | 2 |
| Overall Study | Lost to Follow-up | 2 | 4 |
| Overall Study | Physician Decision | 0 | 2 |
Baseline characteristics
| Characteristic | Rotating Platform High-Flex Cruciate Substituting TKA | Rotating Platform Cruciate Substituting TKA | Total |
|---|---|---|---|
| Age, Continuous | 65 years STANDARD_DEVIATION 7 | 62 years STANDARD_DEVIATION 7 | 64 years STANDARD_DEVIATION 7 |
| Sex: Female, Male Female | 37 Participants | 44 Participants | 81 Participants |
| Sex: Female, Male Male | 34 Participants | 27 Participants | 61 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 9 / 71 | 3 / 71 |
| serious Total, serious adverse events | 7 / 71 | 4 / 71 |
Outcome results
Primary
Clinical Flexion
Maximum, passive flexion and extension of the operated knee joint in the supine position will be measured and recorded using a long goniometer.
Time frame: Preoperative, 4-6 weeks
Population: All subjects with available data at the preoperative and 4-6 week intervals.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Rotating Platform High-Flex Cruciate Substituting TKA | Clinical Flexion | Clinical flexion - preoperative | 119.1 degrees | Standard Deviation 13.2 |
| Rotating Platform High-Flex Cruciate Substituting TKA | Clinical Flexion | Clinical flexion - 4 week | 112.0 degrees | Standard Deviation 12.7 |
| Rotating Platform Cruciate Substituting TKA | Clinical Flexion | Clinical flexion - preoperative | 120.3 degrees | Standard Deviation 11.2 |
| Rotating Platform Cruciate Substituting TKA | Clinical Flexion | Clinical flexion - 4 week | 111.3 degrees | Standard Deviation 15.3 |
Primary
Clinical Flexion
Maximum, passive flexion and extension of the operated knee joint in the supine position will be measured and recorded using a long goniometer.
Time frame: 1 year
Population: All subjects with available data at the 1-year interval.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Rotating Platform High-Flex Cruciate Substituting TKA | Clinical Flexion | 124.2 degrees | Standard Deviation 8.7 |
| Rotating Platform Cruciate Substituting TKA | Clinical Flexion | 124.0 degrees | Standard Deviation 10.3 |
Primary
Clinical Flexion
Maximum, passive flexion and extension of the operated knee joint in the supine position will be measured and recorded using a long goniometer.
Time frame: 4-6 months
Population: All subjects with available data at the 4-6 month interval.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Rotating Platform High-Flex Cruciate Substituting TKA | Clinical Flexion | 122.5 degrees | Standard Deviation 8.6 |
| Rotating Platform Cruciate Substituting TKA | Clinical Flexion | 121.3 degrees | Standard Deviation 9.6 |
Secondary
Knee Society Score (KSS)
A standard clinical evaluation system for reporting results for patients undergoing total knee replacement. The minimum score is 0 and the highest score is 100. A higher score represents a better outcome.
Time frame: 1 year
Population: All subjects with available KSS data at the 1-year interval.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Rotating Platform High-Flex Cruciate Substituting TKA | Knee Society Score (KSS) | Clinical KSS | 95.0 score | Standard Deviation 8.4 |
| Rotating Platform High-Flex Cruciate Substituting TKA | Knee Society Score (KSS) | Functional KSS | 87.7 score | Standard Deviation 19.9 |
| Rotating Platform Cruciate Substituting TKA | Knee Society Score (KSS) | Clinical KSS | 94.9 score | Standard Deviation 8.3 |
| Rotating Platform Cruciate Substituting TKA | Knee Society Score (KSS) | Functional KSS | 90.9 score | Standard Deviation 16 |
Secondary
Oxford Knee Score
A patient reported questionnaire for assessing the outcome of knee surgery. The minimum score is 0 and the maximum score is 48. A higher score represents a better outcome.
Time frame: 1 year
Population: All subjects with available Oxford Knee Score data at the 1-year interval.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Rotating Platform High-Flex Cruciate Substituting TKA | Oxford Knee Score | 41.0 score | Standard Deviation 6.5 |
| Rotating Platform Cruciate Substituting TKA | Oxford Knee Score | 41.8 score | Standard Deviation 7.4 |
Secondary
Radiographic Flexion
Lateral radiographs of the knee will be taken with the patient supine with maximal passive knee flexion. Flexion will then be measured directly from these radiographs.
Time frame: 1 year
Population: All subjects with available data at the 1-year interval.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Rotating Platform High-Flex Cruciate Substituting TKA | Radiographic Flexion | 117.6 degrees | Standard Deviation 11.1 |
| Rotating Platform Cruciate Substituting TKA | Radiographic Flexion | 117.9 degrees | Standard Deviation 11.6 |
Secondary
Radiographic Flexion
Lateral radiographs of the knee will be taken with the patient supine with maximal passive knee flexion. Flexion will then be measured directly from these radiographs.
Time frame: preoperative, 4-6 weeks
Population: All subjects with available data at the preoperative and 4-6 week intervals.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Rotating Platform High-Flex Cruciate Substituting TKA | Radiographic Flexion | 4-6 weeks | 104.7 degrees | Standard Deviation 16.3 |
| Rotating Platform High-Flex Cruciate Substituting TKA | Radiographic Flexion | preoperative | 116.8 degrees | Standard Deviation 14.1 |
| Rotating Platform Cruciate Substituting TKA | Radiographic Flexion | 4-6 weeks | 102.1 degrees | Standard Deviation 16.4 |
| Rotating Platform Cruciate Substituting TKA | Radiographic Flexion | preoperative | 116.6 degrees | Standard Deviation 15.5 |