(29 days)
The Balanced Knee System TriMax PS Plus Tibial Inset is in cemented total knee arthroplasty procedures with the following indications:
- Loss of knee joint configuration and joint function.
- Osteoarthritis of the knee joint.
- Rheumatoid arthritis of the knee joint.
- Post-traumatic arthritis of the knee joint.
- Valgus, varus, or flexion deformities of the knee joint.
- Revision procedures where other treatments or devices have failed.
The Balanced Knee® System (BKS) TriMax PS Plus Tibial Insert is a line extension of the TriMax PS Tibial Insert (K131337) that offers slightly more constraint than the original PS Insert. The PS post geometry is the only design difference between the previously cleared predicate device and the subject device. The change slightly modifies the post's shape to provide additional internal/external and varus/valgus constraint if the surgeon determines the need exists. The balance of the design is identical including the articulating surface, locking mechanism, as well as the PS post location and height. The PS Plus inserts are intended for use in primary and revision knee surgeries with the same indications for use as the predicate. This implant is used with existing BKS and BKS Revision (BKSR) tibial travs. TriMax femoral components and the BKSR modular femoral components. The material is identical as well as all manufacturing processes, cleaning, sterilization and packaging that were cleared under K131337.
This document describes a 510(k) premarket notification for a medical device called the "Balanced Knee® System TriMax PS Plus Tibial Insert." The submission is a "Special 510(k)" because it is a line extension of a previously cleared predicate device (K131337).
Since this is a Special 510(k) for a line extension of an existing device, and the primary change is a slight modification to the PS post geometry, the provided document does not contain information about a study proving the device meets acceptance criteria. Instead, it focuses on demonstrating substantial equivalence to the predicate device through engineering analysis and verification testing.
Therefore, I cannot fulfill the request to provide:
- A table of acceptance criteria and reported device performance (in the context of a clinical study or AI performance evaluation)
- Sample size used for a test set and data provenance
- Number of experts and their qualifications for ground truth
- Adjudication method for a test set
- MRMC comparative effectiveness study results or effect size
- Standalone (algorithm-only) performance
- Type of ground truth used
- Sample size for the training set
- How ground truth for the training set was established
The document describes the engineering and material performance evaluations conducted to demonstrate that the new device's design outputs meet the design inputs, similar to the predicate. The "performance data" section refers to:
- Sterilization: Stated adherence to ISO 11135-1 with a Sterilization Assurance Level (SAL) of 10-6.
- Shelf Life: Validation according to ASTM D4169:2016.
- Biocompatibility: Suitability for implantation verified per ISO 10993.
The comparison of technological characteristics mentions evaluations in the following areas, indicating what was assessed, but not specific acceptance criteria or performance numbers:
- Geometric Analysis
- Contact Area and Pressure
- Constraint
- Wear
- Range of Motion
- PS Post Fatigue
It concludes that "The results showed similar or identical performance indicating that the design outputs of the PS Plus Tibial Insert meet the design inputs." This is a general statement of engineering conformance, not a specific performance metric from a study as typically requested for AI/diagnostic device approvals.
In summary, this document is a 510(k) premarket notification for a mechanical orthopedic implant, not a software or AI-driven medical device. Therefore, the types of studies and acceptance criteria typically associated with AI/software performance evaluations (e.g., sensitivity, specificity, reader studies, ground truth establishment by experts) are not applicable to the content of this FDA letter.
§ 888.3560 Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis.
(a)
Identification. A knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a knee joint. The device limits translation and rotation in one or more planes via the geometry of its articulating surfaces. It has no linkage across-the-joint. This generic type of device includes prostheses that have a femoral component made of alloys, such as cobalt-chromium-molybdenum, and a tibial component or components and a retropatellar resurfacing component made of ultra-high molecular weight polyethylene. This generic type of device is limited to those prostheses intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.