(28 days)
The intended use of the modified device [LOSPA Tibial Base Plate] has not changed as a result of the modification of the predicate device cleared under Lospa Total Knee System, K110404.
The LOSPA Tibial Base Plate which is a component of LOSPA Total Knee System is intended for use in total knee arthroplasty surgery for the following indications:
•Painful, disabling joint disease of the knee resulting from non-inflammatory degenerative Joint disease (including osteoarthritis, traumatic arthritis or avascular necrosis) or rheumatoid arthritis;
•Post-traumatic loss of knee joint configuration and function;
·Moderate varus, valgus, or flexion deformity in which the ligamentous structures can be returned to adequate function and stability;
· Correction or revision of unsuccessful osteotomy, arthrodesis, or failure of previous arthroplasty procedure.
The LOSPA Tibial Base Plate is intended for cemented use only.
The LOSPA Tibial Base Plate is a component of "LOSPA Total Knee System" cleared under K110404 which consists of Femoral Components. Tibial Base plate, Tibial Insert, Patellar Components and Instrumentation - LOSPA Total Knee Instrumentation for use with the system implant components
The current premarket notification is related to the modification of LOSPA Tibial Base Plate design. The modification is specific to the KEEL and the design is similar to predicate device in K110404 and other approved device such as Stryker Scorpio 'NRG' Knee (K030978). Similar to predicate device the tibial base plates (or trays), are available in nine (9) sizes to provide optimal tibial coverage. The tibial base plates are designed for use in either the left or right side, and with either CR or PS femoral components or corresponding tibial inserts.
All tibial base plate components are manufactured from cobalt-chromium-molybdenum alloy conforming to ASTM F75, Standard Specification for Cobalt-28 Chromium-6 Molybdenum Alloy Castings and Casting Alloy for Surgical Implants (UNS R30075).
The AP width ranges from 36 mm, and the ML width ranges from 55 mm to 84 mm. The underside of the base plate features a central keel and stem; the length of the stem is either 35 mm or 40 mm. The stem with keel design is intended to improve the initial stability. In addition, the posterior slope of the keel and stem helps to increase rotational resistance. The base plate is designed to fully capture and lock the polyethylene insert. The surface of the tibial base plate that interfaces with the polyethylene insert includes a ground finish to minimize back side wear of tibial inserts.
Here's an analysis of the provided text regarding the acceptance criteria and supporting study for the LOSPA Tibial Base Plate:
It's important to note that the provided document is a 510(k) summary for a Special 510(k) submission, which focuses on device modification and demonstrating substantial equivalence to a predicate device. Therefore, it does not contain the typical acceptance criteria and detailed study data found in submissions for novel devices or comprehensive clinical trials. Instead, the performance testing described is primarily to demonstrate that the modified device performs similarly to the predicate device and does not raise new safety or efficacy concerns.
Here's a breakdown based on your requested information, with acknowledgements of what is not present in this type of submission:
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Table of Acceptance Criteria and Reported Device Performance
Acceptance Criterion Reported Device Performance Fatigue/Endurance (Mechanical) Performed similar to the predicate device (K110404) based on ASTM F1800/ISO14879-1 and ISO 21536 standards. Modified Instrument Validation (Tibial Keel Punch) Tested and validated. Substantial Equivalence (Overall) Demonstrated based on similar intended use, fundamental scientific technology, operating principles, and materials compared to predicate devices (K110404 and K030978). No new issues of safety or efficacy raised. -
Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Sample Size for Test Set: Not explicitly stated. For mechanical testing, sample sizes are typically determined by the relevant ASTM/ISO standards (e.g., a certain number of samples for fatigue testing). The exact number is not provided in this summary.
- Data Provenance: Not specified, but mechanical testing is typically performed in a laboratory setting, not on patient data.
- Retrospective or Prospective: Not applicable, as this refers to mechanical bench testing, not clinical data.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
- Not applicable. "Ground truth" in this context would refer to expert medical diagnoses or outcomes in a clinical study. The performance testing here is mechanical in nature, comparing the physical properties of the device to established engineering standards and a predicate device.
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Adjudication method (e.g. 2+1, 3+1, none) for the test set
- Not applicable. Adjudication methods like 2+1 or 3+1 are used in clinical studies for resolving discrepancies in expert interpretations (e.g., imaging reads). This submission describes mechanical bench testing.
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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 study is a clinical study involving human readers (e.g., radiologists) interpreting cases, often with and without AI assistance. This document describes a mechanical device and its bench testing.
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If a standalone (i.e. algorithm only without human-in-the loop performance) was done
- Not applicable. This is a physical medical device (a tibial base plate), not a software algorithm.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc)
- The "ground truth" for the mechanical testing is based on established engineering standards (ASTM F1800, ISO14879-1, ISO 21536) and the performance characteristics of the legally marketed predicate device (K110404). The goal is to show that the modified device's mechanical properties are equivalent or better and meet these standards.
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The sample size for the training set
- Not applicable. There is no "training set" in the context of mechanical bench testing for a physical implant. Training sets are relevant for machine learning algorithms.
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How the ground truth for the training set was established
- Not applicable, as there is no training set.
Summary of the Study that Proves the Device Meets Acceptance Criteria:
The study described is primarily a mechanical performance study designed to demonstrate substantial equivalence of the modified LOSPA Tibial Base Plate to its predicate device (Lospa Total Knee System, K110404) and another approved device (Stryker Scorpio 'NRG' Knee, K030978).
The key components of this study included:
- Mechanical Testing: Specifically, fatigue (endurance) testing was performed on the tibial base plate.
- Standards: The testing was carried out using methods described in recognized international and national standards:
- ASTM F1800 (Standard Practice for Cyclical Fatigue Testing of Static and Articulated Internal Spinal Fixation Devices) / ISO14879-1 (Implants for surgery — Knee joint prostheses — Part 1: Determination of endurance properties of knee tibial trays)
- ISO 21536 (Non-active surgical implants — Joint replacement implants — Specific requirements for knee-joint prostheses)
- Comparison: The results of the mechanical testing showed that the LOSPA Tibial Base Plate "performed similar to the predicate device submitted under K110404." This similarity in performance, along with shared design principles, materials, and intended use, formed the basis for the substantial equivalence determination.
- Instrument Validation: The modified instrument, the tibial keel punch, was also "tested and validated." The specific methods or acceptance criteria for this validation are not detailed but imply functional verification.
The underlying "acceptance criteria" not explicitly listed in a bolded table (as would be typical for a clinical study) are implicitly met by demonstrating compliance with the referenced ASTM/ISO standards and achieving performance levels similar to the predicate device. This approach is standard for Special 510(k) submissions focusing on modifications that do not fundamentally alter the device's mechanism of action or safety/efficacy profile, thus relying on established performance benchmarks for similar devices.
§ 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.