The JTS® Extendible Distal Femoral Implant is intended to be used for cemented limb salvage procedures in paediatric (between the ages of 2 and 21) cases where radical resection and replacement of the distal femur is required with the following conditions:

patients suffering from severe arthropathy of the knee that does not respond to any conservative therapy or better alternative surgical treatment;
surgical intervention for severe trauma, revision knee arthroplasties, failed previous prosthesis and/or oncology indications; and
malignant diseases (e.g., osteogenic sarcoma).
The JTS® Extendible Distal Femoral Implant and its components are for single use only.

Device Description

The JTS® Extendible Distal Femoral Implant is a patient specific system that is used to replace bone which is lacking or damaged or must be removed (e g., due to tumor). The device consists of components (defined below) which are available in a range of sizes depending on the size and needs of the patient. Every configuration includes a telescoping shaft with a gearbox, magnet, and extension screw assembly for extending the implant when required by the patient.
Components available in patient specific sizes:

Femoral Telescoping Shaft
Femoral Block
Extension Screw
Femoral Shaft
Tibial configurations for knee joint including passive rotating hinge, rotating hinge (polyethylene), and metal cased tibia components
Passive Bearing
Tibial Passive Stem
HA Coated Extra-cortical Plate that is integral to the Femoral Shaft
Hydroxyapatite Collar that is integral to the Femoral Shaft
Bumper Pad
Bushes
Axles
The specific design of the implant is based on the surgeon's description of the case and patient radiological information. The key dimensions for each JTS® Extendible Distal femoral Implant are derived from the generic device specifications and by taking measurements from the patient's X-rays and/or CT scans. The implant is designed and manufactured for each patient.
The JTS® External Drive Unit is used periodically to lengthen the prosthesis when the patient's limb length discrepancy needs to be addressed. The JTS® External Drive Unit creates a magnetic field which interacts with the magnet in the telescoping shaft to lengthen the implant.

AI/ML Overview

The provided text is a 510(k) summary for the JTS® Extendible Distal Femoral Implant. This document focuses on establishing substantial equivalence to predicate devices for a medical implant.

Based on the content, this document does not describe a study involving performance metrics like sensitivity, specificity, accuracy, or reader improvement in an AI context. Instead, it discusses the technical characteristics, intended use, and substantial equivalence of a physical medical device.

Therefore, many of the requested categories related to AI/algorithm performance studies cannot be filled from the given text.

Here's a breakdown of what can be extracted and explanations for what cannot:

Acceptance Criteria and Device Performance (as described for a physical implant)

The document primarily focuses on establishing substantial equivalence to predicate devices rather than defining specific performance acceptance criteria for a new, standalone study of the device's functional performance in a clinical setting. The "performance" here refers to its design and intended use matching existing cleared devices.

Acceptance Criteria (Implied)	Reported Device Performance
Intended Use: For cemented limb salvage in pediatric patients (2-21) with conditions like severe arthropathy, trauma, failed prostheses, or oncology indications (e.g., osteogenic sarcoma).	Meets Intended Use: The device states the same intended use as its predicate device (K092138).
Technological Characteristics: Similar components, telescoping shaft, gearbox, magnet, extension screw assembly, and patient-specific design based on radiological information.	Meets Technological Characteristics: The device has the same fundamental scientific technology as the predicate. Minor differences are additional optional knee configurations (fixed and rotating hinge tibial designs) and extra-small tibial components, which have themselves been cleared as part of other predicate devices (K120992, K121055, K121029). These do not alter the fundamental technology or raise new safety/effectiveness questions.
Principle of Operation: Telescoping shaft with a gearbox, magnet, and extension screw assembly; uses an external drive unit to create a magnetic field for lengthening.	Meets Principle of Operation: The device has similar principles of operation as its predicate device (K092138).
Safety and Effectiveness: Should not raise new questions of safety or effectiveness compared to predicate devices.	Meets Safety and Effectiveness: The modifications (additional knee configurations) are stated not to "alter the fundamental scientific technology of the JTS® device or raise any new questions of safety or effectiveness."

Information Not Applicable / Not Available from the Provided Text:

The following requested items are specific to the evaluation of AI/algorithm performance and are not found in this 510(k) summary for a physical medical implant.

Sample size used for the test set and the data provenance (e.g., country of origin of the data, retrospective or prospective): Not applicable. This document does not describe a clinical study for performance testing of an algorithm.
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 the AI sense is not established for this device.
Adjudication method (e.g., 2+1, 3+1, none) for the test set: Not applicable.
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.
If a standalone (i.e., algorithm only without human-in-the-loop performance) was done: Not applicable.
The type of ground truth used (expert consensus, pathology, outcomes data, etc.): Not applicable.
The sample size for the training set: Not applicable.
How the ground truth for the training set was established: Not applicable.

In summary, the provided text is a regulatory filing for a physical medical device (an extendable distal femoral implant), not for an artificial intelligence or algorithm-based device. Therefore, the detailed questions about AI performance studies, ground truth establishment, and expert involvement are not applicable to this document.

Summary

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510(k) SUMMARY K133152

Stanmore Implants Worldwide Ltd.'s JTS® Extendible Distal Femoral Implant

JAN 2 2 2014

Submitter's Name, Address, Telephone Number, Contact Person and Date Prepared

Stanmore Implants Worldwide Ltd

Stanmore Implants, 210 Centennial Avenue, Centennial Park, Elstree, WD6 3SJ, United Kingdom

Phone: +44 (0)20 8238 6500 Facsimile:

Contact Person: Jon Charters

Date Prepared: September 30, 2013

. Name of Device and Name/Address of Sponsor

JTS® Extendible Distal Femoral Implant

Stanmore Implants, 210 Centennial Avenue, Centennial Park, Elstree, WD6 3SJ, United Kingdom

Common or Usual Name

Limb salvage system

Classification Name

Knee joint femorotibial metal/polymer constrained cemented prosthesis (21 CFR 888.3510) - KRO

Predicate Devices

JTS® Extendible Implant, Stanmore Implants Worldwide Ltd (K092138) .
METS® SMILES Total Knee Replacement, Stanmore Implants Worldwide Ltd . (K120992)

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METS Modular Total Femoral Replacement. Stanmore Implants Worldwide Ltd (K121055)
METS® Modular Distal Femur, Stanmore Implants Worldwide Ltd (K121029) .

Purpose of the Special 510(k) notice.

The JTS® Extendible Distal Femoral Implant is a modification to the JTS® Extendible Implant.

Intended Use

patients suffering from severe arthropathy of the knee that does not respond to any conservative therapy or better alternative surgical treatment;
동 surqical intervention for severe trauma, revision knee arthroplasties, failed previous prosthesis and/or oncology indications; and
· . malignant diseases (e.g., osteogenic sarcoma).

The JTS® Extendible Distal Femoral Implant and its components are for single use only.

Technological Characteristics

Components available in patient specific sizes:

Femoral Telescoping Shaft .
Femoral Block .

..............................................................................................................................................................................

Extension Screw .
Femoral Shaft �
Tibial configurations for knee joint including passive rotating hinge, rotating hinge . (polyethylene), and metal cased tibia components
Passive Bearing .
Tibial Passive Stem .
HA Coated Extra-cortical Plate that is integral to the Femoral Shaft .
Hydroxyapatite Collar that is integral to the Femoral Shaft .
Bumper Pad .
Bushes ●
. Axles

The specific design of the implant is based on the surgeon's description of the case and patient radiological information. The key dimensions for each JTS® Extendible Distal femoral Implant are derived from the generic device specifications and by taking measurements from the patient's X-rays and/or CT scans. The implant is designed and manufactured for each patient.

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The JTS® External Drive Unit is used periodically to lengthen the prosthesis when the patient's limb length discrepancy needs to be addressed. The JTS® External Drive Unit creates a magnetic field which interacts with the magnet in the telescoping shaft to lengthen the implant.

Substantial Equivalence

JTS® Extendible Distal Femoral Implant has the same intended use and similar principles of operation, and technological characteristics as the cleared JTS® Extendible Implant (K092138). The minor difference between the devices is that the current version of the device includes additional optional knee configurations, including fixed and rotating hinge tibial designs. These new knee components have already been cleared by FDA as part of the METS Smiles Total Knee Replacement (K120992), METS Total Femur (K121055) and the METS Distal Femur (K121029), In addition, extra small tibial components have been added to the system.

These additional knee configurations do not alter the fundamental scientific technology of the UTS® device or raise any new questions of safety or effectiveness. Thus, the JTS® Extendible Distal Femoral Implant is substantially equivalent to its predicate devices.

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Image /page/3/Picture/0 description: The image shows the logo for the U.S. Department of Health and Human Services. The logo consists of a stylized caduceus symbol, which is a staff with two snakes coiled around it, and the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged in a circular pattern around the symbol. The text is in all caps and is oriented to follow the curve of the circle.

DEPARTMENT OF HEALTH & HUMAN SERVICES

Public Health Service

Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002

January 22, 2014

Stanmore Implants Worldwide, Limited % Mr. Gerard J. Prud'homme Partner Hogan Lovells US LLP 555 Thirteenth Street, Northwest Washington, District of Columbia 20004

Re: K133152

Trade/Device Name: JTS® Extendible Distal Femoral Implant Regulation Number: 21 CFR 888.3510 Regulation Name: Knee joint femorotibial metal/polymer constrained cemented prosthesis Regulatory Class: Class II Product Code: KRO Dated: December 23, 2013 Received: December 23, 2013

Dear Mr. Prud'homme:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA), You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices. good manufacturing practice. labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set

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Page 2 - Mr. Gerard J. Prud'homme

forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Division of Small Manufacturers, International and Consumer Assistance at its tollfree number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm. Also. please note the regulation entitled. "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803). please go to

http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.

Sincerely yours.

Ronald#AJean -S for

Mark N. Melkerson Director Division of Orthopedic Devices

Office of Device Evaluation Center for Devices and

Radiological Health

Enclosure

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Indications for Use Statement

510(k) Number (if known):_K133152

Device Name: JTS® Extendible Distal Femoral Implant

Indications for Use:

The JTS® Extendible Distal Femoral Implant is indicated for cemented limb salvage procedures in paediatric (between the ages of 2 and 21) cases where radical resection and replacement of the distal femur is required with the following conditions:

1 patients suffering from severe arthropathy of the knee that does not respond to any conservative therapy or better alternative surgical treatment;
l surgical intervention for severe trauma, revision knee arthroplasties, failed previous prosthesis and/or oncology indications; and
트 malignant diseases (e.g., osteogenic sarcoma).

The JTS® Extendible Distal Femoral Implant and its components are for single use only

Prescription Use X (Per 21 C.F.R. 801.109) AND/OR

Over-The-Counter Use (Per 21 C.F.R. 807 Subpart C)

(PLEASE DO NOT WRITE BELOW THIS LINE -- CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Casey L. Hanley, Ph.D.
Division of Orthopedic Devices

4 રૂટ

Regulation Number and Section

§ 888.3510 Knee joint femorotibial metal/polymer constrained cemented prosthesis.

(a)
Identification. A knee joint femorotibial metal/polymer constrained cemented prosthesis is a device intended to be implanted to replace part of a knee joint. The device limits translation or rotation in one or more planes and has components that are linked together or affined. This generic type of device includes prostheses composed of a ball-and-socket joint located between a stemmed femoral and a stemmed tibial component and a runner and track joint between each pair of femoral and tibial condyles. The ball-and-socket joint is composed of a ball at the head of a column rising from the stemmed tibial component. The ball, the column, the tibial plateau, and the stem for fixation of the tibial component are made of an alloy, such as cobalt-chromium-molybdenum. The ball of the tibial component is held within the socket of the femoral component by the femoral component's flat outer surface. The flat outer surface of the tibial component abuts both a reciprocal flat surface within the cavity of the femoral component and flanges on the femoral component designed to prevent distal displacement. The stem of the femoral component is made of an alloy, such as cobalt-chromium-molybdenum, but the socket of the component is made of ultra-high molecular weight polyethylene. The femoral component has metallic runners which align with the ultra-high molecular weight polyethylene tracks that press-fit into the metallic tibial component. The generic class also includes devices whose upper and lower components are linked with a solid bolt passing through a journal bearing of greater radius, permitting some rotation in the transverse plane, a minimal arc of abduction/adduction. This generic type of device is limited to those prostheses intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.