(266 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.
Example orthopedic surgical procedures include but are not limited to:
- Total Knee Arthroplasty o
- Total Hip Arthroplasty: Anterior / Posterior .
The KneeAlign® 3 System is a computer-controlled system intended to assist the surgeon in determining reference alignment axes in relation to anatomical and instrument and structures during stereotactic orthopedic surgical procedures. The KneeAlign® 3 System facilitates the accurate positioning of implants, relative to these alignment axes.
Example orthopedic surgical procedures include but are not limited to:
- · Total Knee Arthroplasty
The HipAlign 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 HipAlign® System facilitates the accurate positioning of implants, relative to these alignment axes.
Example orthopedic surgical procedures include but are not limited to:
- · Total Hip Arthroplasty: Anterior / Posterior
The OrthAlign Plus" System is an innovative 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.
In knee arthroplasty procedures, the device assists the surgeon in:
- Establishing the mechanical axis of the femur, determining the varus/valgus angle . and the flexion/extension angle of the cutting block relative to femur.
- Establishing the mechanical axis of the tibia, determining the varus/valgus angle . and the posterior slope angle of the cutting block relative to tibia.
In hip arthroplasty procedures, the device assists the surgeon in:
- Establishing the orientation of the anterior pelvic plane and determining the . inclination angle and the anteversion angle of the shell impactor relative to the anterior pelvic plane.
The OrthAlign Plus™ System comprises a single use computer module and reusable instrumentation.
The OrthAlign Plus™ System is usable for a total knee arthroplasty or total hip arthroplasty procedure. The System includes two optional configurations: the KneeAlign® 3 System usable for total knee arthroplasty only, and the HipAlign® System usable for total hip arthroplasty only. The OrthAlign Plus" System includes the singleuse OrthAlign Plus™ Unit, a KneeAlign® 3 Instrument Set and a HipAlign® Instrument Set. The optional configurations include a modified version of the OrthAlign Plus" Unit and only one of the Instrument Sets. Indications for Use for each optional configuration are limited to the applicable orthopedic procedure.
The OrthAlign Plus" System comprises a single use computer module, a reusable reference sensor, a reusable femoral jig, a reusable tibial jig, a reusable posterior hip jig and a reusable anterior hip jig. The device utilizes algorithms to convert sensor outputs into spatial coordinates, providing graphical and numerical representation of instruments and anatomy on the user display screen.
The optional KneeAlign® 3 and HipAlign® system configurations also comprise the single use computer module, reusable reference sensor and applicable reusable jigs. They utilize the same algorithms, sensor conversions, graphical and numerical representations and surgical techniques as the OrthAlign Plus™ System.
The OrthAlign Plus™ System is a computer-assisted surgical navigation system for knee and hip arthroplasty procedures. The submission states that performance testing confirms the system can be used for its intended purpose and demonstrates substantial equivalence to predicate devices.
Here's an analysis of the provided information:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state quantitative "acceptance criteria" or specific metrics for accuracy or precision for the OrthAlign Plus™ System. Instead, it relies on a general statement that "Device performance testing confirms that the OrthAlign Plus™ System can be used according to its intended use."
The performance data describe the types of tests conducted:
- Software verification and validation
- System hardware verification and validation testing
- Electrical safety and electromagnetic compatibility testing
- Instrumentation cleaning, sterilization and shipping validations
- System components biocompatibility assessment
- Customer requirements validation
- System accuracy testing: bench testing with mechanical fixtures and foam models
- Simulated use testing: cadaver and virtual testing
While the report confirms these tests were done, it does not provide specific numerical results that would typically be found in a section detailing acceptance criteria versus actual performance. The primary claim for regulatory clearance is "substantially equivalent" to predicate devices, which implies that its performance is comparable to already approved devices, rather than needing to meet distinct, pre-defined quantitative acceptance thresholds presented in this document.
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Description: Simulated use testing through cadaver and virtual studies.
- Knee Arthroplasty (Prospective Cadaver Validation):
- Simulated operating room environment.
- 3 labs.
- 3 surgeons.
- Procedures performed with both anterior and posterior approaches (though specific numbers for knees are not given, the focus then shifts to hips).
- Hip Arthroplasty – Anterior Approach (Cadaver Labs):
- 2 cadaver labs.
- 30 specimens (30 hips).
- Data Provenance: Prospective, from cadaver labs. Country of origin not specified, but implied to be within the context of the applying company (OrthAlign, Inc. in Aliso Viejo, CA, USA).
- Hip Arthroplasty – Posterior Approach (Cadaver Labs and Virtual Study):
- 2 cadaver labs.
- 12 full body specimens (18 hips).
- Follow-up virtual study (number not specified, but done with software updates).
- Data Provenance: Prospective, from cadaver labs and a subsequent virtual study. Country of origin not specified, but implied USA.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
- Number of Experts: 3 surgeons conducted the procedures in the simulated operating room environment for the initial cadaver validation.
- Qualifications of Experts: Referred to simply as "surgeons." No specific experience levels (e.g., years of experience, board certification) are provided in this summary.
- Method of Ground Truth Establishment: Radiographic evaluation of cup placements was used to validate the navigation of cup angles in hip arthroplasty cadaver labs. The specific methodology for how these surgeons' actions or radiographic interpretations formed the "ground truth" (e.g., if they were the "truth" or if their results were compared to another gold standard) is not fully detailed. It implies that the surgeons used the device, and the outcome (cup placement) was then evaluated radiographically.
4. Adjudication Method for the Test Set
The document does not describe an explicit "adjudication method" (like 2+1 or 3+1 consensus) for establishing ground truth, especially concerning expert agreement on image interpretation or surgical outcomes. It mentions "radiographic evaluation of the cup placements," which implies a measurement-based assessment rather than an adjudication of expert opinions on a diagnostic interpretation. The surgeons were performing the procedures, not adjudicating ground truth.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No MRMC comparative effectiveness study was mentioned. The studies described are performance evaluations of the device itself and its assistance to surgeons, not a comparison of human readers with and without AI assistance to quantify an improvement effect size. The device is a navigation system, assisting in real-time surgical guidance, rather than a diagnostic tool interpreted by multiple readers.
6. Standalone Performance
- Yes, standalone (algorithm only) performance seems to be implicitly covered as part of the overall system testing. The description includes "System accuracy testing: bench testing with mechanical fixtures and foam models" and "virtual testing." These types of tests specifically evaluate the algorithms and hardware in isolation or in a controlled simulated environment before human interaction is introduced in cadaver studies. However, a distinct numerical "standalone performance" metric (e.g., x% accuracy without human intervention) is not explicitly stated.
7. Type of Ground Truth Used
- Measurement-based outcomes:
- For hip arthroplasty cadaver labs, radiographic evaluation of the cup placements was used. This indicates that the "ground truth" was a measurement derived from imaging after the procedure, which was then compared to the intended or desired outcomes guided by the device. This is often considered an objective measurement or an outcome-based ground truth for surgical accuracy.
8. Sample Size for the Training Set
- The document does not specify a separate "training set" sample size or methodology for establishing ground truth for a training set. This is a medical device, specifically a surgical navigation system, rather than a machine learning algorithm that typically requires a large, annotated training dataset in the conventional sense. The "algorithms" mentioned convert sensor outputs into spatial coordinates, suggesting a more deterministic or model-based approach rather than a learning-based approach where a distinct training set (for a neural network, for example) would be used. The "performance data" section focuses on verification and validation of the system rather than training of an AI model.
9. How the Ground Truth for the Training Set Was Established
- As a conventional "training set" (for machine learning) is not described, the concept of establishing ground truth for it is also not applicable here based on the provided text. The device’s "algorithms" are likely based on established biomechanical and geometric principles, and their accuracy is verified through the various testing described (bench, virtual, cadaver), not through training on data with pre-established ground truth labels.
§ 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).