(256 days)
For use as a tool for adjustment of the femoral knee implant to reduce instability from flexion gap asymmetry. The force sensor is sterile. for single patient use.
The device consists of one unit, containing the force sensor and an electronic display. The eLIBRA® Soft-Tissue Force Sensor for a total knee replacement is a single use battery powered device designed to show relative forces on the integrated display. The eLIBRA® Unit is a non-reusable battery powered device designed to receive an electronic signal from the integrated force sensor. The unit displays a number from 0-20 for both the medial and lateral compartments in the knee joint to aid the surgeon in balancing soft tissue structures during a total knee arthroplasty (TKA).
Here's an analysis of the provided text regarding the Synvasive Technology, Inc. eLibra® Soft Tissue Force Sensor (K132104):
This submission is a **Special 510(k) for a device modification, not an entirely new device seeking initial clearance. Therefore, the depth of performance testing and ground truth establishment described is significantly different from what would be expected for a novel device. The primary claim of this submission is substantial equivalence to an existing predicate device (K070108 eLibra 2. Dynamic Knee Balancer).
Description of Acceptance Criteria and Study Findings
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Criteria/Test Description | Reported Device Performance |
|---|---|---|
| Mechanical Testing | Not explicitly detailed, but implied to ensure structural integrity and correct function of the integrated components. | Satisfactory. Revealed no concerns over safety and effectiveness as compared to the predicate device. |
| Force Testing | Not explicitly detailed, but implied to ensure accurate and consistent force measurement by the sensor. | Satisfactory. Revealed no concerns over safety and effectiveness as compared to the predicate device. |
| Electrical Safety | Testing to ensure the device meets electrical safety standards (e.g., preventing shock, electromagnetic compatibility). | Satisfactory. Revealed no concerns over safety and effectiveness as compared to the predicate device. |
| EMC (Electromagnetic Compatibility) | Testing to ensure the device operates correctly in its electromagnetic environment without interfering with or being affected by other devices. | Satisfactory. Revealed no concerns over safety and effectiveness as compared to the predicate device. |
| Sterility Testing | Testing to confirm the device maintains sterility until use (e.g., microbial ingress, package integrity). | Satisfactory. |
| EO Residues | Testing to ensure residual ethylene oxide (EO) levels are within safe limits if EO sterilization is used. | Satisfactory. |
| Software Validation | Testing to confirm the software (for the integrated display) functions correctly and as intended without errors. | Conducted. Results were satisfactory. |
| Risk Analysis | Evaluation of potential risks associated with the device modification and implementation of mitigation strategies. | Conducted. Results were satisfactory, revealing no concerns. |
| Substantial Equivalence | Demonstrating the modified device is as safe and effective as the predicate device. | The tests demonstrated that the device is as safe, as effective, and performs in a substantially equivalent manner to the predicate device. The technical changes (integrated display) do not alter the indications for use or fundamental technological characteristics. |
2. Sample Size for Test Set and Data Provenance
- Sample Size: The document does not specify a distinct "test set" in terms of patient data or a specific number of devices tested for each category. Performance testing was conducted as "bench tests."
- Data Provenance: Not applicable in the context of clinical data for a premarket submission focused on substantial equivalence through bench testing. The data originates from internal company testing (Synvasive Technology, Inc.) in a controlled laboratory environment. This is a retrospective submission based on the company's internal testing data.
3. Number of Experts for Ground Truth and Qualifications
- Experts: Not applicable. For this type of Special 510(k), ground truth is established by engineering and quality assurance personnel through specified test protocols against established standards or internal company specifications derived from the predicate device's performance. Clinical expert consensus is not described as part of this evaluation.
- Qualifications: While not explicitly stated, it's assumed that engineers, quality assurance personnel, and technical experts within Synvasive Technology, Inc., who are proficient in mechanical, electrical, software, and sterility testing, conducted and validated these tests.
4. Adjudication Method for Test Set
- Adjudication Method: Not applicable in the traditional sense of clinical or image-based adjudication. Bench testing results are typically evaluated against pre-defined passing criteria according to test protocols. Any discrepancies or failures would lead to further investigation and re-testing until acceptance criteria are met, or the design is modified.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- Was it done?: No.
- Effect Size: Not applicable. This device is an intraoperative mechanical tool with an integrated display, not an AI-assisted diagnostic or interpretative system that would involve human readers or image analysis. The comparison is against a predicate device, not against human performance.
6. Standalone (Algorithm Only) Performance Study
- Was it done?: Not applicable. The "eLibra® Soft Tissue Force Sensor" is a direct measurement and display device, not an algorithm that performs a standalone diagnostic or predictive task. Its "software" refers to the embedded logic for the display, which was validated as part of software validation.
7. Type of Ground Truth Used
- Ground Truth Type:
- Bench Test Standards/Specifications: Performance was measured against internal engineering specifications, recognized industry standards (e.g., for electrical safety, EMC, sterility), and the known performance characteristics of the predicate device (K070108).
- Expected Functional Output: For force testing, the "ground truth" would be calibrated force values, and the device's readings are compared against these known values. For sterility, the "ground truth" is absence of viable microorganisms.
8. Sample Size for the Training Set
- Sample Size: Not applicable. This device does not use machine learning or AI models that require a separate training set. The "software validation" performed relates to the fixed logic of the embedded system controlling the display, not a learned model.
9. How Ground Truth for the Training Set Was Established
- How Established: Not applicable, as there is no training set for an AI/ML model for this device.
§ 882.4560 Stereotaxic instrument.
(a)
Identification. A stereotaxic instrument is a device consisting of a rigid frame with a calibrated guide mechanism for precisely positioning probes or other devices within a patient's brain, spinal cord, or other part of the nervous system.(b)
Classification. Class II (performance standards).