(150 days)
The Axiom PSR System is intended to be used as patient specific surgical planning and instrumentation to assist in the positioning of total ankle replacement components intraoperatively, and in guiding bone cutting. The Axiom PSR System is intended for use with the Kinos Axiom Total Ankle System and its cleared indications for use.
restor3d's Axiom PSR System is an ankle surgical guide system, designed for an individual patient from the patient's CT imaging scans. The subject Axiom PSR System is intended to aid in the placement of Kinos Axiom Total Ankle System (K192778) implant components when used in conjunction with the Kinos Axiom standard, reusable instruments. The Axiom PSR System includes preoperative plans developed with and approved by the operative surgeon, tibia and talus resection guides, manufactured from implant grade titanium, bone models manufactured from biocompatible polymer for use with the Kinos Axiom Total Ankle System.
The restor3d Axiom PSR System is a patient-specific surgical planning and instrumentation system designed to assist in the positioning of total ankle replacement components intraoperatively and in guiding bone cutting. The information provided does not include specific acceptance criteria with numerical thresholds. However, the study conducted aims to demonstrate that the Axiom PSR System is at least as accurate as, or more accurate than, the previously cleared Kinos Axiom Total Ankle System standard instruments alone, with respect to implant placement relative to the pre-operative plan in six degrees of freedom.
Here's a breakdown of the requested information based on the provided document:
1. Table of Acceptance Criteria and Reported Device Performance:
The document does not provide a table with specific numerical acceptance criteria. Instead, it states a comparative performance objective.
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| The Axiom PSR System should be at least as accurate or more accurate than the Kinos Axiom Total Ankle System standard instruments alone regarding implant placement relative to the pre-operative plan in six degrees of freedom. | Cadaver validation testing demonstrated that the subject Axiom PSR System was at least as accurate or more accurate than using the previously cleared Kinos Axiom Total Ankle System standard instruments alone, with respect to implant placement relative to the preoperative plan in six degrees of freedom. |
2. Sample Size Used for the Test Set and Data Provenance:
- Sample Size for Test Set: The document mentions "cadaver testing" but does not specify the number of cadavers or individual surgical procedures performed.
- Data Provenance: Retrospective or Prospective is not explicitly stated, but "cadaver testing" implies a controlled, experimental setting, likely
prospective for the purpose of the study. The origin (country/region) of the cadavers is not mentioned.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts:
This information is not provided in the document. The ground truth ("pre-operative plans") is established as a digital design workflow, which is later compared to post-operative CT scans. The experts involved in creating these pre-operative plans and evaluating the post-operative scans are not specified.
4. Adjudication Method for the Test Set:
The document mentions that post-operative CT scans were obtained, and the final implant positions were evaluated in 3D space about six degrees of freedom and then compared to the pre-operative plans. It does not describe any specific multi-reviewer adjudication method (e.g., 2+1, 3+1). The evaluation method appears to be a direct comparison of physical outcomes (post-operative CT) to digital plans.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
A multi-reader multi-case (MRMC) comparative effectiveness study was not explicitly stated or described. The study compared the device's performance to the standard method rather than comparing human readers with and without AI assistance. The "AI" aspect is in the patient-specific surgical planning and guiding, not in assisting human readers in diagnosis or interpretation.
6. Standalone Performance (Algorithm Only without Human-in-the-Loop Performance):
This aspect is not directly applicable in the typical sense of standalone AI performance for diagnostic algorithms. The Axiom PSR System is a surgical guidance system, and its "performance" is inherently tied to its use in a surgical setting. The digital design workflow is an algorithmic process that creates the patient-specific guides and plans, but the "standalone" performance isn't measured in isolation from the surgical act. The evaluation "compared to the pre-operative plans" could be considered an evaluation of the system's output (the guides) against its intended design.
7. Type of Ground Truth Used:
The ground truth for comparison was the "pre-operative plans." These plans are a digital design output, established through a digital design workflow. The "final implant positions" from post-operative CT scans were then compared against these pre-operative plans.
8. Sample Size for the Training Set:
The document does not provide any information regarding a training set sample size. The Axiom PSR System is a patient-specific device based on individual patient CT scans, not a machine learning model that requires a separate training set for algorithm development in the traditional sense. The "digital design workflow" is likely based on established biomechanical and engineering principles rather than supervised machine learning requiring a training dataset.
9. How the Ground Truth for the Training Set Was Established:
Since there is no mention of a training set or a machine learning model requiring such a set, this information is not applicable based on the provided document. The device's functionality is based on individual patient imaging and a digital design workflow to create custom surgical guides and plans, not on learning from a large labeled training dataset.
§ 888.3110 Ankle joint metal/polymer semi-constrained cemented prosthesis.
(a)
Identification. An ankle joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace an ankle joint. The device limits translation and rotation in one or more planes via the geometry of its articulating surfaces and has no linkage across-the-joint. This generic type of device includes prostheses that have a talar resurfacing component made of alloys, such as cobalt-chromium-molybdenum, and a tibial resurfacing component made of ultra-high molecular weight polyethylene and is limited to those prostheses intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.