Amputation, Prosthesis User
Conditions
Brief summary
Prospective two group cross over investigation, comparing the investigational device (Power Knee, a powered microprocessor controlled prosthetic knee) and subjects prescribed microprocessor prosthetic knee (MPK). The primary objective was to evaluate the efficacy of the investigational device in reducing exertion during walking compared to passive MPKs. Additionally to evaluate the efficacy of the investigational device in the short and long term compared to passive MPKs and previous versions of the Power Knee, during daily living activities i.e. walking on level ground, in stairs and inclines, rising from and sitting down to a chair as well as performance of gait functions and ease of set up for average to highly active transfemoral/knee disarticulation amputees and Certified Prosthetists/Orthotists (CPOs).
Detailed description
This is a prospective two group cross-over study, within subject comparison. 3 study visits are planned for amputee subjects, with approximately 2-3 weeks between visits, and an optional fourth visit 8-12 weeks after the third visit. During the first visit subjects will be check for inclusion/exclusion, consented and randomly assigned into two groups and Group 1 (transitioning to the investigational device) will perform functional tests and answer questionnaires on the performance of their current prosthesis to provide baseline information. The Group 1 subjects will be fitted and trained on the investigational device and a recommended prosthetic foot which they will use as their prescribed prosthesis for 2-3 weeks until the second visit, the other half will stay on their prescribed prosthesis until the second visit. During the second visit the subjects of Group 1 will perform the same functional tests as in the first visit on the investigational device and answer questionnaires on the performance of the investigational device, and then return to their prescribed prosthesis. The Group 2 will perform the same tests/questionnaires on their prescribed prosthesis and then be fitted and trained on the investigational device and use it as their usual prosthesis for 2-3 weeks. During the third visit all subject will repeat the tests and questionnaires on the prosthesis they are fitted with (Group1 on the prescribed and Group 2 on the investigational device). Subjects will have the option to use the investigational device for an additional 8-12 weeks, those who choose that will be fitted with the investigational device or will stay on it, depending in which they are in at this point. They will be booked for the fourth visit; they will be contacted via telephone 4-5 weeks later and asked to provide feedback on their experience with the device so far. Those that choose not to keep using the investigational device will be returned to their prescribed prosthesis. During the fourth visit subjects will answer the same questionnaires and perform the same functional tests as the other visits. Data will be collected from the knee on activity. They will then be fitted back to their prescribed prosthesis. End of study. CPO (Certified Prosthetist Orthotist) subjects will answer a questionnaire on the ease of setup of the investigational device and provide feedback on the ease of setup of gait functions. Statistical considerations: Outcomes at each timepoint were visually inspected for normality using histograms and qq-plots, as well as a Shapiro-Wilk Normality Test. If the data were deemed to be normal the hypotheses were tested using a two-tailed, paired, student's t-test. Non-normal data was tested using the Wilcoxon signed-rank test.
Interventions
DEVICEPower Knee
Powered microprocessor controlled prosthetic knee
Sponsors
Medical Center Orthotics and Prosthetics
Össur Iceland ehf
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
This is a prospective randomized two group cross-over study, within subject comparison.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* 50Kg\< body weight \< 116Kg * K3-K4 amputees with unilateral transfemoral amputation or Knee disarticulation * Allows for 37mm knee center height to dome of pyramid alignment * Currently using a MPK or Power Knee * Older than 18 years old * No socket issues/changes in the last 6 weeks and no socket changes expected during the duration of the study period. * Comfortable and stable socket fit * Willing and able to participate in the study and follow the protocol
Exclusion criteria
* 50Kg\> body weight \> 116Kg * Bilateral amputees * Users with socket problems * Users with co-morbidities in the contra-lateral limb, which affect their functional mobility * Younger than 18 years old * Users with stump pain * Users with cognitive impairment * Users not involved in other clinical tests and/or receiving treatment that the testing might affect.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Mean Difference in Borg Category Rating Scale Before and After 6MWT at 2 Weeks | At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16) | Mean difference in perceived exertion on the Borg rating scale of perceived exertion before and after 6 minute walk test (6MWT) (see outcome 2) with investigational device (Power Knee) compared to comparator (prescribed device). Subjects are asked how exerted they feel on a scale of 0-10 (0 indicating no exertion and 10 indicating the most exertion) at rest before they carry out the 6MWT, and after carrying out the 6MWT, the difference is recorded. The Borg Category Rating 10 scale (CR10) is a validated measure of perceived exertion. |
| Average Distance Walked in 6 Minute Walk Test | At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16) | Average distance walked in 6MWT with investigational device (Power Knee) compared to comparator (prescribed device) User walk for 6 minutes in their self selected walking speed on a 30 meter track. Shorter time indicates better mobility performance. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13D | At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16) | Average score with investigational device (Power Knee) compared to comparator (prescribed device) of modified PEQ Question 13D Over the past 2 weeks, please rate your ability in the following activities when using your prosthesis : • Question 13D.Your safety when walking downstairs using the prosthesis The scale used is a Likert Scale 1-10 (1 indicating low rating of safety and 10 indicating a high rating of safety). |
| Satisfaction With Walking Speed | At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16) | Proportion of subjects reporting satisfaction with walking speed on investigational device |
| Prosthetic Limb Users Survey of Mobility (PLUS-M) T-score | At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16) | Ability to ambulate over typical environmental obstacles measured by the Prosthetic Limb Users Survey of Mobility (PLUS-M), T-score with Power Knee compared to comparator (prescribed device). The Prosthetic Limb Users Survey of Mobility™ is a self-report instrument for measuring mobility of adults with lower limb amputation. Scoring a PLUS-M short form produces a T-score. To find the T-score, the scores must be summed for all responses on the short form (creating a raw score). Then the raw score needs to be used to determine the T-score in the conversation table provided with the PLUS-M questionnaire. The T-score is a standardized score with a mean of 50 and a standard deviation of 10. A higher T-score indicates a higher level of mobility. The highest possible T-score is 71.4 and the lowest one is 21.8. |
| Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13A | At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16) | Average score with investigational device (Power Knee) compared to comparator (prescribed device) of modified PEQ Question 13A Over the past 2 weeks, please rate your ability in the following activities when using your prosthesis : • Question 13A. Your safety (during stance phase) when walking with your prosthesis (prescribed device) /test prosthesis (Power Knee)? The scale used is a Likert Scale 1-10 (1 indicating low rating of safety and 10 indicating a high rating of safety). |
| Average Score of Prosthesis Evaluation Questionnaire (PEQ) Question 1D | At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16) | Average score with investigational device (Power Knee) compared to comparator (prescribed device) of modified PEQ Question 1D Over the past 2 weeks, please rate your ability in the following activities when using your prosthesis : • Question 1D. Your comfort while standing when using your prosthesis/test prosthesis? The scale used is a Likert Scale 1-10 (1 indicating low rating of safety and 10 indicating a high rating of safety). |
| Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 9 and 10 | At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16) | Support in sit to stand and stand to sit evaluation: Total score (minimum score 0 - maximum score 8) of Prosthetic Mobility Questionnaire (PMQ) questions 9 and 10 with investigational device (Power Knee) compared to comparator (prescribed knee): PMQ : Over the past 2 weeks, please rate your ability in the following activities when using your prosthesis (0=no ability, 4=fully able): * Question 9. To sit down and get up from a chair with a high seat (e.g. a dining chair, an office chair) * Question 10. To sit down and get up from a low, soft chair (e.g. a deep sofa) A higher total score on these PMQ items indicates a better outcome as it reflects greater functional ability, independence, and overall quality of life for individuals using a prosthesis. The total score is obtained by summing the scores from questions 9 and 10. |
| Proportion of Participants With Average Score Over 5 on Questions 3K and 3L of the Prosthesis Evaluation Questionnaire (PEQ) With the Investigational Device | After 2 weeks of either using the Power Knee or their own prescribed knee | Proportion of participants with Average score with investigational device of PEQ questions 3K and 3L over 5 PEQ- Questions 3K, 3L: * Question 3K: Over the past two weeks, rate how often the test prosthesis made squeaking, clicking, or belching sounds The scale used is a Likert Scale 1-10 (1 indicating low frequency of prosthesis making sounds and 10 indicating a high frequency of the prosthesis making sounds). * Question 3L: 3L: If it made any sounds in the past four weeks, rate how bothersome these sounds were to you. - Or check It made no sounds The scale used is a Likert Scale 1-10 (1 indicating low frequency of prosthesis making sounds and 10 indicating a high frequency of the prosthesis making sounds). Support question (yes/no) Would the noise from the test device prevent you from preferring it as your usual prosthesis? |
| Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 1 and 3-6: | At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16) | Total score of PMQ questions 1,3-6 (minimum score 0 - maximum score 20): PMQ (Questions 1 and 3-6): Over the past 2 weeks, please rate your ability in the following activities when using your prosthesis: * Question 1: To walk indoors * Question 3: To walk upstairs * Question 4: To walk downstairs * Question 5: To walk up a steep hill * Question 6: To walk down a steep hill The scale used is a Likert scale 0-4 (0= Unable or hardly able at all, 1= High difficulty, 2= Moderate Difficulty, 3= Little difficulty, 4= No problems or almost fully able). |
| Time Required to Complete the L-test | At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16) | The L-Test of Functional Mobility consists of a series of movements designed to assess an individual's physical function and dynamic balance. The test involves the participant starting from a seated position, standing up, walking a short distance, turning, walking back, and returning to the seated position. The course typically forms an L shape, which includes two turns, and the total distance covered is longer than that of similar tests like the Timed Up and Go (TUG) test. The outcome measure is the time taken to complete these movements, providing an objective evaluation of the participant's functional mobility. There is no fixed minimum or maximum; lower times indicate better performance (i.e., faster completion reflects greater mobility). |
| Average Prosthetic Mobility Questionnaire (PMQ) Total Score | At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16) | Average Prosthetic Mobility Questionnaire (PMQ) total score (minimum score 0 - maximum score 48) with investigational device (Power Knee) compared to comparator (prescribed device). The Prosthetic Mobility Questionnaire is a tool for assessing mobility in people with lower-limb amputation, higher score indicates better mobility performance. |
| Occurrence of Side Effects That Could be Directly Related to Using the Power Knee | After 2 weeks of using the Power Knee | Evaluating the occurrence of side effects associated with the Power Knee entails systematically documenting and analyzing any adverse effects experienced by users throughout the 2 weeks of use. |
| Average Score Regarding the Ease of Setup | Immediately after the intervention (fitting of the investigational device) | Self reported ease of setup of investigational device compared to state of the art microprocessor knees (SOTA MPKs) and previous version of the investigational device. Average score with investigational device (Power Knee) compared to comparator (previous version of Power Knee) and compared to state of the art microprocessor knees (SOTA MPKs) The scale used is a Likert Scale 1-10 (1 indicating low rating and 10 indicating a high rating). |
| Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 14F | At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16) | Average score with investigational device (Power Knee) compared to comparator (prescribed device) of modified PEQ Question 14F Modified PEQ question 14F : Over the past 2 weeks, please rate your ability in the following activities when using your prosthesis : • Question 14F. Your safety when walking down a steep hill using the prosthesis The scale used is a Likert Scale 1-10 (1 indicating low rating of safety and 10 indicating a high rating of safety). |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Combined Crossover Evaluation Group For the analysis, data from both arms were combined.
In Group 1, participants initially used the investigational device, with the second visit corresponding to its evaluation after two weeks of use, and evaluated their prescribed device during the third visit, also after two weeks of use.
In Group 2, participants started with the prescribed device, evaluating it during the second visit after two weeks of use, and switched to the investigational device for the evaluation during the third visit, again after two weeks of use. | 17 |
| Total | 17 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Excluded | 0 | 1 |
| Overall Study | Physician Decision | 2 | 0 |
| Overall Study | Withdrawal by Subject | 3 | 0 |
Baseline characteristics
| Characteristic | Combined Crossover Evaluation Group | — |
|---|---|---|
| Age, Continuous | 52 years | — |
| Amputation level Transfemoral | 17 Participants | — |
| Race and Ethnicity Not Collected | — | — Participants |
| Region of Enrollment United States | 17 Participants | — |
| Sex: Female, Male Female | 0 Participants | — |
| Sex: Female, Male Male | 17 Participants | — |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 17 | 0 / 17 |
| other Total, other adverse events | 3 / 17 | 0 / 17 |
| serious Total, serious adverse events | 0 / 17 | 0 / 17 |
Outcome results
Primary
Average Distance Walked in 6 Minute Walk Test
Average distance walked in 6MWT with investigational device (Power Knee) compared to comparator (prescribed device) User walk for 6 minutes in their self selected walking speed on a 30 meter track. Shorter time indicates better mobility performance.
Time frame: At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16)
Population: Only 6 out of the 11 subjects decided to do a prolonged follow up period.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Distance Walked in 6 Minute Walk Test | At Baseline : Prescribed knee | 369.2 meters | Standard Deviation 113.4 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Distance Walked in 6 Minute Walk Test | After 2 weeks: Prescribed knee | 377.2 meters | Standard Deviation 108.6 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Distance Walked in 6 Minute Walk Test | After 2 weeks: Power Knee | 381.7 meters | Standard Deviation 137.1 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Distance Walked in 6 Minute Walk Test | After a prolonged follow up period: Power Knee | 393.1 meters | Standard Deviation 112.1 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Distance Walked in 6 Minute Walk Test | After 2 weeks: Prescribed knee | 390.7 meters | Standard Deviation 136 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Distance Walked in 6 Minute Walk Test | After 2 weeks: Power Knee | 402.5 meters | Standard Deviation 151.5 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Distance Walked in 6 Minute Walk Test | At Baseline : Prescribed knee | 381.5 meters | Standard Deviation 140.3 |
Primary
Mean Difference in Borg Category Rating Scale Before and After 6MWT at 2 Weeks
Mean difference in perceived exertion on the Borg rating scale of perceived exertion before and after 6 minute walk test (6MWT) (see outcome 2) with investigational device (Power Knee) compared to comparator (prescribed device). Subjects are asked how exerted they feel on a scale of 0-10 (0 indicating no exertion and 10 indicating the most exertion) at rest before they carry out the 6MWT, and after carrying out the 6MWT, the difference is recorded. The Borg Category Rating 10 scale (CR10) is a validated measure of perceived exertion.
Time frame: At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16)
Population: Only 6 out of the 11 subjects decided to do a prolonged follow up period.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Mean Difference in Borg Category Rating Scale Before and After 6MWT at 2 Weeks | At Baseline: Prescribed knee | 3.4 score on a scale | Standard Deviation 1.6 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Mean Difference in Borg Category Rating Scale Before and After 6MWT at 2 Weeks | After 2 weeks : Prescribed knee | 3.1 score on a scale | Standard Deviation 1.5 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Mean Difference in Borg Category Rating Scale Before and After 6MWT at 2 Weeks | After 2 weeks : Power Knee | 3.4 score on a scale | Standard Deviation 2.5 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Mean Difference in Borg Category Rating Scale Before and After 6MWT at 2 Weeks | After a prolonged follow up period : Power Knee | 3.2 score on a scale | Standard Deviation 0.7 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Mean Difference in Borg Category Rating Scale Before and After 6MWT at 2 Weeks | After 2 weeks : Prescribed knee | 2.5 score on a scale | Standard Deviation 0.9 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Mean Difference in Borg Category Rating Scale Before and After 6MWT at 2 Weeks | After 2 weeks : Power Knee | 2.8 score on a scale | Standard Deviation 1.7 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Mean Difference in Borg Category Rating Scale Before and After 6MWT at 2 Weeks | At Baseline: Prescribed knee | 3.3 score on a scale | Standard Deviation 1.4 |
Secondary
Average Prosthetic Mobility Questionnaire (PMQ) Total Score
Average Prosthetic Mobility Questionnaire (PMQ) total score (minimum score 0 - maximum score 48) with investigational device (Power Knee) compared to comparator (prescribed device). The Prosthetic Mobility Questionnaire is a tool for assessing mobility in people with lower-limb amputation, higher score indicates better mobility performance.
Time frame: At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16)
Population: Only 6 out of the 11 subjects decided to do a prolonged follow up period.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Prosthetic Mobility Questionnaire (PMQ) Total Score | At Baseline: Prescribed Knee | 31.5 score on a scale | Standard Deviation 9.8 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Prosthetic Mobility Questionnaire (PMQ) Total Score | After 2 weeks: Prescribed Knee | 31.2 score on a scale | Standard Deviation 10.3 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Prosthetic Mobility Questionnaire (PMQ) Total Score | After 2 weeks: Power Knee | 35.5 score on a scale | Standard Deviation 7.4 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Prosthetic Mobility Questionnaire (PMQ) Total Score | After a prolonged follow up period: Power Knee | 35.2 score on a scale | Standard Deviation 5.6 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Prosthetic Mobility Questionnaire (PMQ) Total Score | After 2 weeks: Prescribed Knee | 29.8 score on a scale | Standard Deviation 9.8 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Prosthetic Mobility Questionnaire (PMQ) Total Score | After 2 weeks: Power Knee | 37.3 score on a scale | Standard Deviation 4.5 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Prosthetic Mobility Questionnaire (PMQ) Total Score | At Baseline: Prescribed Knee | 31.5 score on a scale | Standard Deviation 7.2 |
Secondary
Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13A
Average score with investigational device (Power Knee) compared to comparator (prescribed device) of modified PEQ Question 13A Over the past 2 weeks, please rate your ability in the following activities when using your prosthesis : • Question 13A. Your safety (during stance phase) when walking with your prosthesis (prescribed device) /test prosthesis (Power Knee)? The scale used is a Likert Scale 1-10 (1 indicating low rating of safety and 10 indicating a high rating of safety).
Time frame: At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16)
Population: Only 6 out of the 11 subjects decided to do a prolonged follow up period.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13A | At Baseline: Prescribed Knee | 8.6 score on a scale | Standard Deviation 1.4 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13A | After 2 weeks: Prescribed Knee | 8.5 score on a scale | Standard Deviation 1.7 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13A | After 2 weeks: Power Knee | 8.4 score on a scale | Standard Deviation 2.1 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13A | After a prolonged follow up period: Power Knee | 8.0 score on a scale | Standard Deviation 4 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13A | After 2 weeks: Prescribed Knee | 8.3 score on a scale | Standard Deviation 1.9 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13A | After 2 weeks: Power Knee | 9.0 score on a scale | Standard Deviation 1.6 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13A | At Baseline: Prescribed Knee | 8.7 score on a scale | Standard Deviation 1.2 |
Secondary
Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13D
Average score with investigational device (Power Knee) compared to comparator (prescribed device) of modified PEQ Question 13D Over the past 2 weeks, please rate your ability in the following activities when using your prosthesis : • Question 13D.Your safety when walking downstairs using the prosthesis The scale used is a Likert Scale 1-10 (1 indicating low rating of safety and 10 indicating a high rating of safety).
Time frame: At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16)
Population: Only 6 out of the 11 subjects decided to do a prolonged follow up period.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13D | At baseline: Prescribed Knee | 7.7 score on a scale | Standard Deviation 1.9 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13D | After 2 weeks: Prescribed Knee | 7.8 score on a scale | Standard Deviation 2 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13D | After 2 weeks: Power Knee | 9.2 score on a scale | Standard Deviation 0.8 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13D | After a prolonged follow up period: Power Knee | 8.2 score on a scale | Standard Deviation 4 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13D | After 2 weeks: Prescribed Knee | 7.2 score on a scale | Standard Deviation 2.2 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13D | After 2 weeks: Power Knee | 9.5 score on a scale | Standard Deviation 0.6 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 13D | At baseline: Prescribed Knee | 7.7 score on a scale | Standard Deviation 1.6 |
Secondary
Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 14F
Average score with investigational device (Power Knee) compared to comparator (prescribed device) of modified PEQ Question 14F Modified PEQ question 14F : Over the past 2 weeks, please rate your ability in the following activities when using your prosthesis : • Question 14F. Your safety when walking down a steep hill using the prosthesis The scale used is a Likert Scale 1-10 (1 indicating low rating of safety and 10 indicating a high rating of safety).
Time frame: At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16)
Population: Only 6 out of the 11 subjects decided to do a prolonged follow up period.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 14F | At Baseline: Prescribed knee | 7.3 score on a scale | Standard Deviation 2 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 14F | After 2 weeks : Prescribed knee | 7.1 score on a scale | Standard Deviation 2.4 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 14F | After 2 weeks : Power Knee | 7.9 score on a scale | Standard Deviation 1.6 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 14F | After a prolonged follow up period: Power Knee | 6.7 score on a scale | Standard Deviation 3.4 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 14F | After 2 weeks : Prescribed knee | 6.8 score on a scale | Standard Deviation 2 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 14F | After 2 weeks : Power Knee | 8.3 score on a scale | Standard Deviation 1.2 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Modified Prosthesis Evaluation Questionnaire (PEQ) Question 14F | At Baseline: Prescribed knee | 6.8 score on a scale | Standard Deviation 1.8 |
Secondary
Average Score of Prosthesis Evaluation Questionnaire (PEQ) Question 1D
Average score with investigational device (Power Knee) compared to comparator (prescribed device) of modified PEQ Question 1D Over the past 2 weeks, please rate your ability in the following activities when using your prosthesis : • Question 1D. Your comfort while standing when using your prosthesis/test prosthesis? The scale used is a Likert Scale 1-10 (1 indicating low rating of safety and 10 indicating a high rating of safety).
Time frame: At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16)
Population: Only 6 out of the 11 subjects decided to do a prolonged follow up period.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score of Prosthesis Evaluation Questionnaire (PEQ) Question 1D | At Baseline: Prescribed Knee | 8.6 score on a scale | Standard Deviation 1.1 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score of Prosthesis Evaluation Questionnaire (PEQ) Question 1D | After 2 weeks: Prescribed Knee | 8.5 score on a scale | Standard Deviation 1.2 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score of Prosthesis Evaluation Questionnaire (PEQ) Question 1D | After 2 weeks: Power Knee | 9.0 score on a scale | Standard Deviation 2.1 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Prosthesis Evaluation Questionnaire (PEQ) Question 1D | After a prolonged follow up period: Power Knee | 7.7 score on a scale | Standard Deviation 3.4 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Prosthesis Evaluation Questionnaire (PEQ) Question 1D | After 2 weeks: Prescribed Knee | 8.0 score on a scale | Standard Deviation 1.4 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Prosthesis Evaluation Questionnaire (PEQ) Question 1D | After 2 weeks: Power Knee | 9.5 score on a scale | Standard Deviation 0.8 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Average Score of Prosthesis Evaluation Questionnaire (PEQ) Question 1D | At Baseline: Prescribed Knee | 8.3 score on a scale | Standard Deviation 1.4 |
Secondary
Average Score Regarding the Ease of Setup
Self reported ease of setup of investigational device compared to state of the art microprocessor knees (SOTA MPKs) and previous version of the investigational device. Average score with investigational device (Power Knee) compared to comparator (previous version of Power Knee) and compared to state of the art microprocessor knees (SOTA MPKs) The scale used is a Likert Scale 1-10 (1 indicating low rating and 10 indicating a high rating).
Time frame: Immediately after the intervention (fitting of the investigational device)
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score Regarding the Ease of Setup | Power Knee | 9.0 score on a scale | Standard Deviation 1.3 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score Regarding the Ease of Setup | Previous version of Power Knee | 6.5 score on a scale | Standard Deviation 3.3 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Average Score Regarding the Ease of Setup | SOTA MPKs | 8.6 score on a scale | Standard Deviation 1.2 |
Secondary
Occurrence of Side Effects That Could be Directly Related to Using the Power Knee
Evaluating the occurrence of side effects associated with the Power Knee entails systematically documenting and analyzing any adverse effects experienced by users throughout the 2 weeks of use.
Time frame: After 2 weeks of using the Power Knee
Population: For this outcome measure, side effects were assessed only after 2 weeks of Power Knee use. Although the study followed a crossover design, the timing or order in which participants used each device did not affect the evaluation of side effects. No side effect data were collected for the prescribed prosthesis; therefore, results are reported solely for the Power Knee group, reflecting all participants who completed the 2-week evaluation. Reporting by arm is not applicable for this outcome.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Occurrence of Side Effects That Could be Directly Related to Using the Power Knee | 0 side effect |
Secondary
Proportion of Participants With Average Score Over 5 on Questions 3K and 3L of the Prosthesis Evaluation Questionnaire (PEQ) With the Investigational Device
Proportion of participants with Average score with investigational device of PEQ questions 3K and 3L over 5 PEQ- Questions 3K, 3L: * Question 3K: Over the past two weeks, rate how often the test prosthesis made squeaking, clicking, or belching sounds The scale used is a Likert Scale 1-10 (1 indicating low frequency of prosthesis making sounds and 10 indicating a high frequency of the prosthesis making sounds). * Question 3L: 3L: If it made any sounds in the past four weeks, rate how bothersome these sounds were to you. - Or check It made no sounds The scale used is a Likert Scale 1-10 (1 indicating low frequency of prosthesis making sounds and 10 indicating a high frequency of the prosthesis making sounds). Support question (yes/no) Would the noise from the test device prevent you from preferring it as your usual prosthesis?
Time frame: After 2 weeks of either using the Power Knee or their own prescribed knee
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Proportion of Participants With Average Score Over 5 on Questions 3K and 3L of the Prosthesis Evaluation Questionnaire (PEQ) With the Investigational Device | 72 percentage of participants |
Secondary
Prosthetic Limb Users Survey of Mobility (PLUS-M) T-score
Ability to ambulate over typical environmental obstacles measured by the Prosthetic Limb Users Survey of Mobility (PLUS-M), T-score with Power Knee compared to comparator (prescribed device). The Prosthetic Limb Users Survey of Mobility™ is a self-report instrument for measuring mobility of adults with lower limb amputation. Scoring a PLUS-M short form produces a T-score. To find the T-score, the scores must be summed for all responses on the short form (creating a raw score). Then the raw score needs to be used to determine the T-score in the conversation table provided with the PLUS-M questionnaire. The T-score is a standardized score with a mean of 50 and a standard deviation of 10. A higher T-score indicates a higher level of mobility. The highest possible T-score is 71.4 and the lowest one is 21.8.
Time frame: At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16)
Population: Only 6 out of the 11 subjects decided to do a prolonged follow up period
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Prosthetic Limb Users Survey of Mobility (PLUS-M) T-score | At Baseline: Prescribed Knee | 53.1 score on a scale | Standard Deviation 9.1 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Prosthetic Limb Users Survey of Mobility (PLUS-M) T-score | After 2 weeks: Power Knee | 57.2 score on a scale | Standard Deviation 7.9 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Prosthetic Limb Users Survey of Mobility (PLUS-M) T-score | After 2 weeks: Prescribed Knee | 51.7 score on a scale | Standard Deviation 10.2 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Prosthetic Limb Users Survey of Mobility (PLUS-M) T-score | After a prolonged follow up period: Power Knee | 56.3 score on a scale | Standard Deviation 6.3 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Prosthetic Limb Users Survey of Mobility (PLUS-M) T-score | After 2 weeks: Prescribed Knee | 51.9 score on a scale | Standard Deviation 10.1 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Prosthetic Limb Users Survey of Mobility (PLUS-M) T-score | After 2 weeks: Power Knee | 57.9 score on a scale | Standard Deviation 6.2 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Prosthetic Limb Users Survey of Mobility (PLUS-M) T-score | At Baseline: Prescribed Knee | 54.1 score on a scale | Standard Deviation 8.3 |
Secondary
Satisfaction With Walking Speed
Proportion of subjects reporting satisfaction with walking speed on investigational device
Time frame: At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16)
Population: Only 6 out of the 11 subjects decided to do a prolonged follow up period.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Satisfaction With Walking Speed | 100 percentage of participants |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Satisfaction With Walking Speed | 100 percentage of participants |
Secondary
Time Required to Complete the L-test
The L-Test of Functional Mobility consists of a series of movements designed to assess an individual's physical function and dynamic balance. The test involves the participant starting from a seated position, standing up, walking a short distance, turning, walking back, and returning to the seated position. The course typically forms an L shape, which includes two turns, and the total distance covered is longer than that of similar tests like the Timed Up and Go (TUG) test. The outcome measure is the time taken to complete these movements, providing an objective evaluation of the participant's functional mobility. There is no fixed minimum or maximum; lower times indicate better performance (i.e., faster completion reflects greater mobility).
Time frame: At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16)
Population: Only 6 out of the 11 subjects decided to do a prolonged follow up period.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Time Required to Complete the L-test | At Baseline: Prescribed Knee | 23.7 seconds | Standard Deviation 8.2 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Time Required to Complete the L-test | After 2 weeks: Prescribed Knee | 24.2 seconds | Standard Deviation 9.4 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Time Required to Complete the L-test | After 2 weeks: Power Knee | 26.3 seconds | Standard Deviation 11.9 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Time Required to Complete the L-test | After a prolonged follow up period: Power Knee | 24.1 seconds | Standard Deviation 10.8 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Time Required to Complete the L-test | After 2 weeks: Prescribed Knee | 23.8 seconds | Standard Deviation 11.7 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Time Required to Complete the L-test | After 2 weeks: Power Knee | 25.2 seconds | Standard Deviation 12.6 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Time Required to Complete the L-test | At Baseline: Prescribed Knee | 23.0 seconds | Standard Deviation 10 |
Secondary
Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 1 and 3-6:
Total score of PMQ questions 1,3-6 (minimum score 0 - maximum score 20): PMQ (Questions 1 and 3-6): Over the past 2 weeks, please rate your ability in the following activities when using your prosthesis: * Question 1: To walk indoors * Question 3: To walk upstairs * Question 4: To walk downstairs * Question 5: To walk up a steep hill * Question 6: To walk down a steep hill The scale used is a Likert scale 0-4 (0= Unable or hardly able at all, 1= High difficulty, 2= Moderate Difficulty, 3= Little difficulty, 4= No problems or almost fully able).
Time frame: At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16)
Population: Only 6 out of the 11 subjects decided to do a prolonged follow up period.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 1 and 3-6: | After 2 weeks: Prescribed Knee | 14.2 score on a scale | Standard Deviation 4.3 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 1 and 3-6: | After 2 weeks: Power Knee | 15.6 score on a scale | Standard Deviation 3.4 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 1 and 3-6: | At Baseline: Prescribed Knee | 13.8 score on a scale | Standard Deviation 4.2 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 1 and 3-6: | After a prolonged follow up period: Power Knee | 15.8 score on a scale | Standard Deviation 2.9 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 1 and 3-6: | After 2 weeks: Prescribed Knee | 13.3 score on a scale | Standard Deviation 4.2 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 1 and 3-6: | At Baseline: Prescribed Knee | 13.2 score on a scale | Standard Deviation 3.4 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 1 and 3-6: | After 2 weeks: Power Knee | 16.7 score on a scale | Standard Deviation 2.4 |
Secondary
Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 9 and 10
Support in sit to stand and stand to sit evaluation: Total score (minimum score 0 - maximum score 8) of Prosthetic Mobility Questionnaire (PMQ) questions 9 and 10 with investigational device (Power Knee) compared to comparator (prescribed knee): PMQ : Over the past 2 weeks, please rate your ability in the following activities when using your prosthesis (0=no ability, 4=fully able): * Question 9. To sit down and get up from a chair with a high seat (e.g. a dining chair, an office chair) * Question 10. To sit down and get up from a low, soft chair (e.g. a deep sofa) A higher total score on these PMQ items indicates a better outcome as it reflects greater functional ability, independence, and overall quality of life for individuals using a prosthesis. The total score is obtained by summing the scores from questions 9 and 10.
Time frame: At baseline, after 2 weeks of either using the Power knee or their own prescription prosthesis, and at the fourth follow-up (at approximately weeks 22-16)
Population: Only 6 out of the 11 subjects decided to do a prolonged follow up period.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 9 and 10 | At baseline: Prescribed knee | 5.6 score on a scale | Standard Deviation 2.2 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 9 and 10 | After 2 weeks: Prescribed knee | 5.8 score on a scale | Standard Deviation 1.9 |
| Combined Crossover Evaluation Group Combined Crossover Evaluation Group | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 9 and 10 | After 2 weeks: Power Knee | 6.8 score on a scale | Standard Deviation 1.3 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 9 and 10 | After a prolonged follow up period: Power Knee | 6.3 score on a scale | Standard Deviation 1.2 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 9 and 10 | After 2 weeks: Prescribed knee | 5.7 score on a scale | Standard Deviation 2.1 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 9 and 10 | After 2 weeks: Power Knee | 7.2 score on a scale | Standard Deviation 1 |
| Subset of 6 Subjects Who Opted for a Prolonged Follow up Period | Total Score of Prosthesis Mobility Questionnaire (PMQ) Questions 9 and 10 | At baseline: Prescribed knee | 6.0 score on a scale | Standard Deviation 1.4 |