Search Results

The NexGen LPS Trabecular Metal Monoblock Tibia is intended for use where severe degeneration, trauma, or other pathology of the knee joint indicates cemented total knee arthroplasty.

The NexGen LPS TM Monoblock Tibia is manufactured from Trabecular Metal (Hedrocel Porous Tantalum) with direct compression molded ultra-high molecular weight polyethylene (UHMWPE).

Here's an analysis of the provided documents regarding your request for acceptance criteria and study information:

Analysis of Provided Document for Acceptance Criteria and Study Information:

The provided documents are a 510(k) Summary of Safety and Effectiveness and an FDA Clearance Letter for "The NexGen LPS TM Monoblock Tibia." These types of documents are regulatory filings for medical devices and do not typically contain detailed information about specific performance studies, acceptance criteria, sample sizes, ground truth establishment, or expert involvement as one would find in a clinical trial report or a scientific publication.

The primary purpose of a 510(k) submission is to demonstrate substantial equivalence to an already legally marketed device (predicate device), not to prove de novo safety and effectiveness through extensive clinical trials for a novel device. Therefore, much of the requested information is not present in these documents.

Missing Information:

Crucially, the provided material does not include any data or studies that would directly prove the device meets specific acceptance criteria in the way you've outlined for performance metrics (e.g., sensitivity, specificity, accuracy). This type of information is common for AI/ML-based diagnostic devices, but this document is for a physical orthopedic implant (a knee replacement component).

For a physical implant, "acceptance criteria" and "study" would typically refer to:

• Mechanical Testing standards: e.g., fatigue life, strength, wear testing, fixation strength, and biocompatibility testing. These are usually conducted according to ISO or ASTM standards.
• Clinical Outcomes (often much later stage/post-market): e.g., revision rates, patient reported outcomes, complication rates. These are rarely part of a 510(k) submission unless there's a significant change to a previously cleared device.

The 510(k) summary only states that the device is "substantially equivalent to the identified predicate devices." This substantial equivalence is typically based on:

• Similar Indications for Use.
• Similar Technological Characteristics: This refers to materials, design principles, and sometimes mechanical testing data showing comparable performance to the predicate device under specific standardized conditions. However, the details of these tests are not in the summary.
• Safety Profile: Implied to be similar to the predicate device.

Based on the provided text, here is what can be inferred or explicitly stated regarding your questions:

1. A table of acceptance criteria and the reported device performance:

• Acceptance Criteria: Not explicitly stated in terms of performance metrics (e.g., "X% sensitivity", "Y% accuracy"). For an orthopedic implant, acceptance criteria would typically be defined by compliance with recognized standards for mechanical properties, biocompatibility, and manufacturing quality, and demonstration of similar characteristics to a predicate device. The document states a "Conclusion: The NexGen LPS TM Monoblock Tibia is substantially equivalent to the identified predicate devices." This "substantial equivalence" is the overarching acceptance criterion addressed.
• Reported Device Performance: No specific performance data (e.g., fatigue life, wear rates, clinical success rates) is reported in these summary documents. The performance is implied to be equivalent to the predicate devices.

2. Sample size used for the test set and the data provenance (e.g., country of origin of the data, retrospective or prospective):

• Not Applicable / Not Provided: As this is a 510(k) for a physical implant demonstrating substantial equivalence, there isn't a "test set" in the context of diagnostic algorithm validation. The "study" here refers to the comparison against predicate devices and any underlying engineering or biocompatibility tests, the details of which are not disclosed in this summary.

3. 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 / Not Provided: This question is relevant for diagnostic devices that rely on expert interpretation for ground truth. For a physical implant, "ground truth" would relate to its physical and biological performance, evaluated through engineering tests, material science, and potentially animal studies (though not mentioned here). Expert review would be internal to the manufacturer and FDA, not typically published in this format.

4. Adjudication method (e.g., 2+1, 3+1, none) for the test set:

• Not Applicable / Not Provided: This pertains to expert consensus for diagnostic interpretation, which is not relevant for this type of device and submission.

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:

• Not Applicable: This type of study is specifically for AI-assisted diagnostic tools that human readers interact with. The NexGen LPS TM Monoblock Tibia is a physical knee implant and does not involve human readers interpreting AI output.

6. If a standalone (i.e. algorithm only, without human-in-the-loop performance) was done:

• Not Applicable: This is an AI/algorithm-specific question and does not apply to a physical medical implant.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):

• Inferred based on device type: For an orthopedic implant, the "ground truth" for demonstrating substantial equivalence and safety would involve:
  • Material properties data: Chemical composition, mechanical strength, porosity.
  • Biocompatibility testing: Standardized tests for cytotoxicity, sensitization, irritation, etc. (often in vitro or animal studies).
  • Mechanical testing: Fatigue, wear, pull-out strength, etc., typically performed to industry standards (e.g., ISO, ASTM).
  • Design comparison: Detailed comparison of the geometric features and manufacturing processes to the predicate device.
• None of these are explicitly detailed in the provided summary.

8. The sample size for the training set:

• Not Applicable: This question applies to machine learning algorithms. There is no concept of a "training set" for a physical implant submission like this 510(k).

9. How the ground truth for the training set was established:

• Not Applicable: As above, this is an AI/ML-specific question and does not apply.

Summary of Device and Regulatory Context (from the provided text):

• Device Name: The NexGen LPS™ Monoblock Tibia
• Manufacturer: Implex Corp.
• Device Type: Tibial Component (for knee replacement surgery)
• Material: Trabecular Metal (Hedrocel Porous Tantalum) with direct compression molded ultra-high molecular weight polyethylene (UHMWPE).
• Indication for Use: "severe degeneration, trauma, or other pathology of the knee joint indicates cemented total knee arthroplasty."
• Regulatory Pathway: 510(k) Premarket Notification
• Key Determination: Substantial Equivalence to predicate devices.
• FDA Clearance Date: February 20, 2002 (corrected from original letter date of Feb 12, 2002 via K020295).

In conclusion, the provided documents are insufficient to answer the majority of your questions because they are summaries of a 510(k) submission for a physical medical implant, which follows a different regulatory and validation paradigm than AI/ML diagnostic tools.

Ask a specific question about this device