|
|
| General |
| Study Status |
Delayed |
Application Number /
Requirement Number |
H200001 / PAS001 |
| Date Original Protocol Accepted |
02/17/2021
|
| Date Current Protocol Accepted |
12/19/2022
|
| Study Name |
Patient Specific Talus Spacer PAS
|
| Device Name |
Patient Specific Talus Spacer
|
| General Study Protocol Parameters |
| Study Design |
Prospective Cohort Study
|
| Data Source |
New Data Collection
|
| Comparison Group |
Objective Performance Criterion
|
| Analysis Type |
Analytical
|
| Study Population |
Adult: >21
|
| Detailed Study Protocol Parameters |
| Study Objectives |
The study objective is to evaluate the continued safety and probable benefit of the Talus Spacer in commercial use. The Patient Specific Talus Spacer PAS is a prospective, single-arm, multicenter US observational study to provide ongoing safety and probable benefit assessment of the Patient Specific Talus Spacer in treatment of avascular necrosis of the ankle.
|
| Study Population |
50 adult subjects who have been diagnosed with avascular necrosis (AVN) in the ankle joint
|
| Sample Size |
A minimum number of 50 patients will be enrolled in this study. Of the 50 subjects, a minimum of 20 subjects will receive a Cobalt Chromium Patient Specific Talus Spacer and a minimum of 20 subjects will receive a Titanium (Ti6Al4V) with Titanium Nitride (TiN) coating Patient Specific Talus Spacer. The total sample size is based on both the safety and probable benefit hypotheses, accounts for 10% lost-to-follow-up, and ensures 90% statistical power using an unadjusted chi-square test with a 1-sided type 1 error rate of a = 0.05. The failure rate with device removal or serious device-related adverse event by Year 5 of the patient specific talus spacer is assumed to be lower than the failure rate with a non-union of the comparator, tibiotalocalcaneal fusion with allograft. For patients without failure, a >=20-point improvement on a 100-point scale for the Visual Analog Scale (VAS) pain scale at 5 years compared to baseline is assumed. The sample size for each material group is determined to ensure statistical power for the subgroup analysis.
|
| Key Study Endpoints |
Primary Probable Benefit Endpoint:
The primary probable benefit endpoint is a clinically significant improvement in pain, as demonstrated by a = 20-point improvement on a 100-point scale for the Visual Analog Scale (VAS) pain scale at 5 years compared to baseline. Patients who undergo an SSSI will be defined as probable benefit endpoint failures. Therefore, a patient will achieve the primary probable benefit endpoint only if they do not undergo an SSSI and they achieve a = 20-point improvement in VAS pain.
Primary Safety Endpoint:
Based on the need for a subsequent secondary surgical intervention (SSSI) or Device Related Serious Adverse Events (“SAEs”) at 5 years post-procedure.
The following secondary safety endpoints will also be assessed:
• Adverse events (“AEs”)
• Device - or procedure related AEs
• Serious AEs (“SAEs”)
Additional Analyses:
Improvement at 5 years post-procedure compared to Pre-op on:
• Ankle ROM;
• FAOS for:
a. Pain
b. Symptom
c. Sport/Rec
d. Activities of Daily Living (“ADL”); and
e. Quality of Life (“QoL”)
Other Exploratory Analyses:
• X-ray Assessment and Measurements:
a. Tibiotalar Alignment
b. Talar Tilt Angle
c. Boehler’s Angle
d. Talar declination angle
e. Meary’s angle
|
| Follow-up Visits and Length of Follow-up |
5 years
|
| Interim or Final Data Summary |
| Interim Results |
Safety Results
There have been seven (7) serious adverse events (SAEs) which occurred in five (5) patients. Five (5) of the SAEs are determined to be probably related to the device. There have been two (2) device removals in two (2) patients. There have been seven (7) reoperations in two (2) patients.
Effectiveness Results
VAS Pain: mean = 64.1 (N=20; SD=18.3) at pre-op; mean=41.1 (N=19; SD=26.69) at 6 weeks; mean=37.3 (N=19; SD=25.37) at 3 months; mean=24.1 (N=15; SD=26.12) at 6 months; mean=26.9 (N=11; SD=32.93) at 12 months; 0 (N=1) at 24 months. The VAS satisfaction with surgical results at 12 months were as follows: 9.1% (1/11) Fair, 27.3% (3/11) Good, and 63.6% (7/11) very satisfied (excellent). FAOS Symptom Subscale Scores: mean = 40.4 (SD=13.27) at pre-op; mean = 62.0 (N=20; SD=11.37) at 6 weeks; mean=54.5 (N=19; SD=8.65) at 3 months; mean=53.8 (N=19; SD=12.27) at 6 months; mean = 51.9 (N=11; SD=12.41) at 12 months; 67.9 (N=1) at 24 months; FAOS Pain Subscale Scores: mean = 31.4 (N=20; SD=15.43) at pre-op; mean = 45.2 (N=19; SD=19.57) at 6 weeks; mean=54.8 (N=19; SD=18.28) at 3 months; mean=60.8 (N=15; SD=26.04) at 6 months; mean = 69.4 (N=11; SD=22.74) at 12 months; 97.2 (N=1) at 24 months. FAOS ADL Subscale Scores: mean = 41.8 (N=20; SD=20.41) at pre-op; mean = 55.3 (N=19; SD=20.23) at 6 weeks; mean=62.5 (N=19; SD=18.73) at 3 months; mean=66.0 (N=15; SD=26.08) at 6 months; mean = 77.8 (N=11; SD=22.83) at 12 months; 100.0 (N=1) at 24 months. FAOS Sport/Rec Subscale Scores: mean = 11.5 (N=20; SD=15.31) at pre-op; mean = 25.5 (N=19; SD=29.81) at 6 weeks; mean=36.1 (N=19; SD=30.71) at 3 months; mean=41.0 (N=15; SD=32.30) at 6 months; mean = 55.9 (N=11; SD=36.32) at 12 months; 100.0 (N=1) at 24 months. FAOS QoL Subscale Scores: mean = 8.9 (N=20; SD=13.95) at pre-op; mean = 23.0 (N=19; SD=16.01) at 6 weeks; mean=34.2 (N=19; SD=19.69) at 3 months; mean=46.9 (N=15; SD=23.27) at 6 months; mean = 51.7 (N=11; SD=27.68) at 12 months; 100.0 (N=1) at 24 months. Ankle ROM Scores: mean = 39.8 (N=20; SD=14.71) at pre-op; mean = 35.2 (N=19; SD=12.32) at 6 weeks; mean=39.0 (N=19; SD=13.90) at 3 months; mean=48.9 (N=15; SD=15.62) at 6 months; mean = 50.5 (N=11; SD=18.17) at 12 months.
|
| Actual Number of Patients Enrolled |
Twenty-one (21) subjects enrolled
|
| Actual Number of Sites Enrolled |
Seven (7) sites enrolled
|
| Patient Follow-up Rate |
73.3% (11 actual patients / 15 expected patients) at 12 months post operative; 100% (1 actual patients / 1 expected patients) at 2 years post operative
|
