(91 days)
The OrthAlign Plus® System is a computer-controlled system intended to assist the surgeon in determining reference alignment axes in relation to anatomical and instrumentation structures during stereotactic orthopedic surgical procedures. The OrthAlign Plus® System facilitates the accurate positioning of implants, relative to these alignment axes. The system aids the surgeon in controlling leg length and offset discrepancies in Total Hip Arthroplasty.
Example orthopedic surgical procedures include but are not limited to:
- · Total Knee Arthroplasty
- · Total Hip Arthroplasty: Anterior/Posterior
- · Unicompartmental Knee Arthroplasty: Tibial transverse resection
The OrthAlign Plus® System is a non-invasive computer assisted surgical navigation system for use in knee and hip arthroplasty procedures. The OrthAlign Plus® System is configured to detect, measure, and display angular and positional measurement changes in a triaxial format. The OrthAlign Plus® System utilizes a palm-sized computer module and reference sensor to generate positional information in orthopedic procedures providing a sequence of steps for registration of anatomical landmarks, calculation of mechanical axes, and positioning of instruments relative to the mechanical axes.
Here's an analysis of the provided text to extract information about the acceptance criteria and the study that proves the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance
The document doesn't explicitly state numerical acceptance criteria in a table format, nor does it provide specific numerical performance metrics for the device. Instead, it describes "performance testing" and states that the "OrthAlign Plus® System can be used according to its intended use" and "performs as well as or better than the predicate devices."
However, we can infer the tested capabilities and the reported validation of those capabilities.
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Accuracy of Leg Length and Offset Measurement (THA, Anterior) | - Bench testing with mechanical fixtures and foam models verified leg length and offset measurement accuracy. |
- Simulated use testing in cadavers validated system accuracy vs. the gold standard of radiographic measurement.
- 40 data points (on 5 hips) from cadaver validation showed accurate measurement of intraoperative change in leg length and offset. |
| Accuracy of Acetabular Shell Insertion Navigation (THA, Anterior, relative to anterior pelvic plane adjusted for pelvic tilt) | - Bench testing with mechanical fixtures and foam models verified updated scale reader measurement accuracy (likely contributing to this). - Simulated use testing in cadavers validated system accuracy vs. the gold standard of radiographic measurement.
- 38 data points (on 5 hips) from cadaver validation showed accurate navigation of cup placement angles. |
| Software Integrity and Functionality | Software verification and validation ensured the integrity of the code and functionality and reliability of the software in various use sequences. |
| Hardware Mechanical Requirements | System hardware verification/validation testing ensured the electronics hardware meets its mechanical requirements. |
| Electrical Safety | Electrical safety testing to IEC 60601-1:2005 + Corr. 1 (2006) + Corr. 2 (2007) + AM1 (2012) or IEC 60601-1:2012. |
| Electromagnetic Compatibility | Electromagnetic compatibility testing to IEC 60601-1-2: 2015. |
| Laser Product Safety | Laser product safety verification to IEC 60825-1:2014. |
| Instrumentation Cleaning, Sterilization, and Shipping | Validations for the specified processes. |
| Navigation Device Sterilization, Packaging, Shelf Life, Environmental, Shipping | Validations for the specified ranges of conditions involved in each process. (Summary data for the identical predicate device is referenced for some validations.) |
| Biocompatibility | System components biocompatibility assessment per ISO 10993-1 (2009). |
| User Requirements Validation (Simulated Use) | Customer requirements validation with an advising surgeon validated the system meets design input requirements for its functions in a simulated use environment. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size (for clinical performance aspects):
- Intraoperative change in leg length and offset: 40 data points (on 5 hips)
- Acetabular shell insertion navigation: 38 data points (on 5 hips)
- Data Provenance: Prospective cadaver validation in a simulated operating room environment. The country of origin is not specified.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
- Number of Experts: A "surgeon" conducted the procedures in the simulated use cadaver testing. It mentions "an advising surgeon" for customer requirements validation. The exact number of independent experts contributing to ground truth establishment for the cadaver study is not explicitly stated beyond "a surgeon."
- Qualifications of Experts: The individual conducting the cadaver procedures is referred to as a "surgeon." No specific years of experience or subspecialty (e.g., orthopedic surgeon) are mentioned, though the context implies an orthopedic surgeon familiar with the procedures.
4. Adjudication Method for the Test Set
The document does not describe an adjudication method for the test set in the sense of multiple reviewers resolving discrepancies. The ground truth (radiographic evaluation) was compared against the device's measurements.
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
No, an MRMC comparative effectiveness study involving human readers with and without AI assistance was not performed or described. This device is a surgical navigation system, not an AI-assisted diagnostic tool that aids human readers.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
Yes, the cadaver study described is a standalone performance test of the algorithm and system's accuracy in a simulated surgical environment. The "surgeon" conducts the procedure using the device, and the device's output (measurements and navigation guidance) is then compared to a ground truth (radiographic evaluation). This assesses the system's ability to accurately determine surgical parameters independently, under realistic conditions.
7. The Type of Ground Truth Used
- Radiographic measurement: Used for validating the accuracy of leg length and offset changes, and cup placement angles in the hip arthroplasty procedures on cadavers. This is considered a "gold standard" in the context of the study.
8. The Sample Size for the Training Set
The document does not mention a "training set" or "training data" as this device is a rule-based surgical navigation system rather than a machine learning/AI model that requires training data in the conventional sense. The "performance data" section focuses on verification and validation of the system's design and functionality.
9. How the Ground Truth for the Training Set Was Established
As no training set is discussed or implied for a machine learning model, this question is not applicable based on the provided text. The system relies on its inherent algorithms and sensor data, validated against known physical principles and clinically accepted measurement techniques (like radiography) rather than being "trained" on a dataset with established ground truth.
§ 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).