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The NOVOS-NAIL Limb Lengthening System is indicated for limb lengthening of the femur and tibia.

The Smith & Nephew NOVOS-NAIL Limb Lengthening System (NOVOS-NAIL LLS) is composed of a modular implantable intramedullary rod, locking screws, and an external actuator. The modular implantable rod is available in different configurations, lengths, and diameters to accommodate a variety of patient anatomies. The system uses locking screws and nail caps (optional) previously cleared with the TRIGEN Nail system (K981529).

The NOVOS-NAIL implant includes an enclosed rare earth magnet, telescoping lead screw/nut assembly and gearing. The subject device is supplied sterile by gamma sterilization. The external actuator is supplied non sterile.

This is a set of acceptance criteria for a medical device called the NOVOS-NAIL Limb Lengthening System (LLS). The acceptance criteria and supporting studies are presented below:

1. Table of Acceptance Criteria and Reported Device Performance

2. Sample size used for the test set and the data provenance:

• Finite Element Analysis (FEA): The sample size refers to the digital models created. Specific numbers are not provided, but it states "8mm and 11mm NOVOS Limb Lengthening Nails" were analyzed.
• Construct Fatigue Testing: "8mm and 11mm NOVOS-NAIL and the predicate device" were tested.
• Bending Fatigue Evaluation: "8mm and 11mm NOVOS- NAIL" were tested.
• Distraction Accuracy: "8mm and 11mm nail" were tested.
• Usability Testing: The document mentions "A human factors validation was conducted," but does not specify the number of participants.
• Bacterial Endotoxin Testing: Not explicitly stated, but typically involves a batch or representative samples of the sterilized device.
• Static Bend Strength: "8mm and 11mm NOVOS-NAIL" were tested.

The provenance of the data is not explicitly stated in terms of country of origin or whether it was retrospective or prospective. It refers to pre-clinical testing, which is generally conducted in a laboratory setting.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

This information is not provided. The studies outlined are primarily mechanical and usability tests, which typically rely on objective measurements and established standards rather than expert consensus for ground truth establishment. For the usability study, "human factors validation" implies involvement of human factors specialists, but their specific qualifications or number are not detailed.

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

No adjudication method is mentioned for any of the described tests. The nature of these pre-clinical tests (mechanical and engineering analyses) usually involves direct measurement against pre-defined specifications rather than subjective assessment requiring adjudication.

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:

No MRMC comparative effectiveness study was done. This device is a mechanical implant for limb lengthening and does not involve AI or human "readers" in its primary function, so such a study would not be applicable.

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

This question is not applicable as the device is a mechanical implant and does not involve an algorithm. The "external actuator" mentioned is a mechanical control, not an AI algorithm.

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

The ground truth for these pre-clinical tests is established by:

• Engineering Specifications and Standards: For structural strength, fatigue, bending, distraction accuracy, and static bend strength, the ground truth is derived from established mechanical engineering principles, material science, and relevant industry standards (e.g., for fatigue testing, bending strength).
• Regulatory Guidance: For bacterial endotoxin testing, the ground truth is "acceptable endotoxin limits as stated in the FDA Guidance, 'Submission and Review of Sterility Information in Premarket Notification (510(k)) Submissions for Devices Labeled as Sterile,' and 'Pyrogen and Endotoxin Testing: Questions and Answers,' and ANSI/AAMI ST72."
• Human Factors Principles: For usability testing, the ground truth is based on principles of human factors engineering and user experience to identify and mitigate use-related risks.

8. The sample size for the training set:

Not applicable. This document describes pre-clinical testing for a physical medical device, not a machine learning model, so there is no concept of a "training set" in this context.

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

Not applicable, as there is no training set for this type of device.

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The Ellipse MAGEC Spinal Bracing and Distraction System is intended for skeletally immature patients less than 10 years of age with severe progressive spinal deformities (e.g., Cobb angle of 30 degrees or more; thoracic spine height less than 22 cm) associated with or at risk of Thoracic Insufficiency Syndrome (TIS). TIS is defined as the inability of the thorax to support normal respiration or lung growth.

The Ellipse Technologies, Inc. MAGEC Spinal Bracing and Distraction System is comprised of a sterile single use spinal rod that can be surgically implanted using appropriate Stryker® Xia fixation components (i.e. Pedicle screws, hooks and/or connectors). The system includes a non-sterile hand held External Remote Controller (ERC) that is used at various times after implant to non-invasively lengthen the implanted spinal rod. The implanted spinal rod is used to brace the spine during growth to minimize the progression of scoliosis. The titanium rod (Ti-6Al-4V ASTM F136) includes an actuator portion that holds a small internal magnet. The magnet in the actuator can be turned non-invasively by use of the ERC. Rotation of the magnet causes the MAGEC rod to be lengthened or shorten.

The hand held non-invasive ERC is electrically powered. The ERC is placed over the patient's spine and then manually activated, which causes the implanted magnet to rotate and either lengthen or shorten the rod. Periodic lengthening of the rod is performed to distract the spine and to provide adequate bracing during growth to minimize the progression of scoliosis. Once the physician determines that the implant has achieved its intended use and is no longer required, the implant is explanted. Additional accessories for the MAGEC System include the MAGEC Manual Distractor and the MAGEC Wand Magnet Locator. The MAGEC Manual Distractor is a sterilizable, single use device, which is used in the operating room to test the device prior to implantation. The MAGEC Wand Magnet Locator is a non-sterile device which is used during the distraction procedure to locate the magnet within the MAGEC rod. The ERC is placed over this location on the child's back.

The provided text describes the MAGEC® Spinal Bracing and Distraction System and its premarket notification (K140178) to the FDA. The submission focuses on establishing substantial equivalence to a predicate device, the Harrington Rod System, rather than providing detailed acceptance criteria and a study proving the device meets those criteria in the context of a diagnostic AI product.

Therefore, much of the requested information (acceptance criteria, specific performance metrics, sample sizes for test/training sets, expert qualifications, adjudication methods, MRMC studies, standalone performance with specific metrics like sensitivity/specificity, and detailed ground truth establishment for training) cannot be extracted from the provided document as it pertains to a mechanical medical device rather than a diagnostic AI.

However, I can extract information related to the device's performance evaluation.

Here's the information that can be extracted and a clear statement about what cannot:

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

The document does not provide a table of numerically defined acceptance criteria for a diagnostic AI product. Instead, it describes performance in terms of mechanical and clinical outcomes for a spinal bracing system.

• Shelf Life Packaging Validation (ISO 11607-1): Performed.
• Sterilization (ANSI/AAMI/ISO 11137-2): "Verification that the gamma radiation sterilization process provides a sterility assurance level of 10-6."
• Biocompatibility (ISO 10993-1): Performed.
• Device functionality and verification: Performed.
• Electrical Safety (IEC 60601-1): Performed.
• Electrical Interference and Compatibility (EMC/EMI) (EN 60601-1-2): Performed.
• Magnetic Field Safety (ICNIRP 2009): Performed.
• Software (FDA Guidance (May 11, 2005)): Performed. |
  | In Vivo (Animal) Study | Safe and efficient non-invasive distraction of the spine in an animal model. | - Porcine Model (9 male Yucatan pigs): "Results of the in vivo porcine study demonstrates that the MAGEC System is safe and provides an efficient means of non-invasive distraction of the spine. No complications from distraction occurred." Attempted and actual distraction were recorded. |
  | Clinical Performance | Safety and probable benefit, including deformity correction, continued growth, and reduced need for subsequent surgical procedures, similar to traditional growing rods. | - Retrospective clinical study (outside US): "The results of the clinical study showed the MAGEC System provides the benefits of spinal deformity correction and continued growth, similar to that for traditional growing rods, without the need for regular surgical lengthening procedures in these children."
• Specific endpoints assessed: Cobb angle correction, thoracic spine height increase, improvement in space available for lung (SAL), coronal and sagittal balance, reduction in number of subsequent surgical procedures, and weight gain.
• Demonstrated ability for non-invasive adjustment to lengthen the implanted rod, allowing continued spinal growth and increased Thoracic Spine Height. |

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

• Test Set Sample Size:
  • In Vivo (Animal) Study: 9 male Yucatan pigs (randomly assigned to two groups: 1 (MAGEC rod) and 2 (sham)).
  • Clinical Study: Not explicitly stated, but described as a "retrospective clinical study for children who had either a primary or revision spinal bracing procedure using the MAGEC System."
• Data Provenance:
  • In Vivo Study: Porcine model (animal study).
  • Clinical Study: "evaluated outside the United States" (retrospective).

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)

This information is not provided in the document. The studies performed were primarily in vivo animal studies and a retrospective clinical study focusing on device performance and clinical outcomes, not on establishing ground truth for a diagnostic AI.

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

This information is not provided as it is not relevant to the type of device and studies described.

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

This information is not provided as it is not relevant to the type of device (spinal bracing system) and evaluation presented. It's a study design typically used for diagnostic imaging AI.

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

This information is not provided as it is not relevant to the type of device described, which is a physical, implantable medical device, not a standalone diagnostic algorithm.

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

• Non-Clinical and In Vivo Studies: Ground truth was based on physical measurements, functional specifications, and observation of physiological responses (e.g., distraction achieved, lack of complications) in controlled experimental settings.
• Clinical Performance Data: Ground truth or "probable benefit" was assessed based on clinical outcomes data such as Cobb angle correction, thoracic spine height increase, improvement in space available for lung (SAL), coronal and sagittal balance, reduction in subsequent surgical procedures, and weight gain.

8. The sample size for the training set

This information is not provided as there is no mention of a "training set" in the context of an AI/algorithm-based device. The device is mechanical with non-invasive magnetic actuation.

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

This information is not provided as there's no training set for an AI in this context.

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