The ELEOS™ Limb Salvage System is indicated for resection and replacement of the proximal femur; intercalary portion of the femur, total femur, distal femur, and proximal tibia in skeletally mature patients with the following conditions:

Non-inflammatory degenerative joint disease such as osteoarthritis, avascular necrosis, ankylosis, protrusion acetabuli, and painful hip dysplasia;
Inflammatory degenerative joint disease such as rheumatoid arthritis;
Correction of functional deformity
Revision procedures where other treatments or devices have failed; and,
Treatment of fractures that are unmanageable using other techniques.

The ELEOS Limb Salvage System is also indicated for procedures where resection and replacement of the proximal femur, intercalary portion of the femur, distal femur, and proximal tibia is required with the following conditions:

Patients suffering from severe arthropathy of the hip and/or knee that does not respond to any conservative therapy or better alternative surgical treatment;
Surgical intervention for severe trauma, revision hip or knee arthroplasties, and/or Oncology indications.
Metastatic diseases

Device Description

The Onkos Surgical ELEOS™ Limb Salvage System consists of components that are used in the reconstruction of the lower limb. The reconstruction are proximal femur, intercalary portion of the femur, distal femur, total femur, proximal tibia, and hinged knee. The ELEOS Limb Salvage components are femoral head, proximal femur, female stem, mid-section, segmental stem, distal femur, tibial hinge assembly, axial pin, tibial poly spacer, tibial baseplate, male-male mid section, resurfacing femur, proximal tibia, patella, stem extension, and tibial wedges and augments. Instrumentation is provided non-sterile in surgical trays which are to be re-processed per validated instructions.

AI/ML Overview

The provided text is a 510(k) Summary for a medical device called the ELEOS™ Limb Salvage System. This document focuses on demonstrating substantial equivalence to previously cleared predicate devices, rather than proving the device meets specific acceptance criteria through a clinical study with performance metrics like sensitivity, specificity, or accuracy.

Therefore, many of the requested details about acceptance criteria, sample sizes, expert ground truth, adjudication methods, MRMC studies, standalone performance, and ground truth establishment are not applicable or available in this type of submission.

Here's an analysis of the available information:

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

This information is not provided in the document. The 510(k) summary focuses on demonstrating substantial equivalence through a risk-based evaluation and comparison of technological characteristics, rather than reporting specific performance metrics against pre-defined acceptance criteria.

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

This information is not provided. As no new performance testing was required (see point 5.7), there was no "test set" in the context of typical AI/software performance studies. The evaluation was based on a risk assessment and comparison to existing predicate devices.

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. Since no new performance testing with a ground truth was conducted, this is not applicable.

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

This information is not provided. Not applicable for the reasons stated above.

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. An MRMC comparative effectiveness study is not mentioned. The device is a "Limb Salvage System" (a physical implantable medical device), not an AI-powered diagnostic or assistive tool for human readers.

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

This information is not provided. This concept is not applicable as the device is a physical implant, not an algorithm.

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

This information is not provided. Not applicable for the reasons stated above.

8. The sample size for the training set

This information is not provided. The device is an orthopedic implant, not an AI model that requires a "training set."

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

This information is not provided. Not applicable as there is no training set for this type of device.

Summary of what is provided regarding the "study" for substantial equivalence:

Device: ELEOS™ Limb Salvage System (K211677)
Purpose of Submission: To add a new indication for use (intercalary replacement) to the existing ELEOS™ Limb Salvage System, consistent with the predicate DePuy LPS System, and to introduce a female stem component.
Predicate Devices:
- Primary Predicate: ELEOS™ Limb Salvage System, Onkos Surgical, Inc., K161520
- Predicate: Orthogenesis LPS System, DePuy, Inc., K003182
Method of "Proof":
- Technological Characteristics Comparison: The submission compares the technological characteristics of the subject device (including the new female stem) to the predicate devices. It notes that the design of the female stem utilizes the same material, segmental taper, cement flutes, and length as the primary predicate.
- Risk-Based Evaluation: A risk-based evaluation determined that the addition of the female stem for intercalary replacement does not raise new concerns with respect to safety and/or effectiveness.
- Conclusion of Risk Evaluation: This evaluation demonstrated "no new or increased risks related to loosening, subsidence, fatigue, dissociation, and/or fretting corrosion compared to the primary predicate device."
- Performance Data: "additional performance testing was not required to support this submission" because the risk-based evaluation showed no new concerns.
- Clinical Data: "Clinical data was not deemed necessary for the subject device."
Overall Conclusion (5.9): Based on the comparisons and risk assessment, the subject device is deemed substantially equivalent to the primary predicate and predicate devices, implying that any differences do not raise new questions of safety and effectiveness, and the proposed device is at least as safe and effective as the legally marketed predicate devices.

In essence, the "study" here is a design comparison and risk assessment against an already cleared device, demonstrating that the modifications (new indication and component) do not introduce new safety or effectiveness risks compared to the predicate devices. It relies on the prior clearance information of the predicate devices.

Summary

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July 28, 2021

Image /page/0/Picture/1 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). The logo consists of two parts: on the left, there is the Department of Health & Human Services logo, which features a stylized caduceus symbol. To the right of this is the FDA logo, which includes the letters "FDA" in a blue square, followed by the words "U.S. FOOD & DRUG ADMINISTRATION" in blue text.

Onkos Surgical Matthew (Matt) Vernak Vice President, Quality and Regulatory 77 East Halsey Rd Parsippany, New Jersey 07054

Re: K211677

Trade/Device Name: ELEOS™ Limb Salvage System Regulation Number: 21 CFR 888.3510 Regulation Name: Knee Joint Femorotibial Metal/Polymer Constrained Cemented Prosthesis Regulatory Class: Class II Product Code: KRO, JDI, JWH, LPH, LZO Dated: June 1, 2021 Received: June 1, 2021

Dear Matthew (Matt) Vernak:

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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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

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801); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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 https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.

For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

Ting Song, PhD Assistant Director DHT6A: Division of Joint Arthroplasty Devices OHT6: Office of Orthopedic Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K211677

Device Name ELEOSTM Limb Salvage System

Indications for Use (Describe)

Non-inflammatory degenerative joint disease such as osteoarthritis, avascular necrosis, ankylosis, protrusion acetabuli, and painful hip dysplasia;
Inflammatory degenerative joint disease such as rheumatoid arthritis;
Correction of functional deformity
Revision procedures where other treatments or devices have failed; and,
Treatment of fractures that are unmanageable using other techniques.

Patients suffering from severe arthropathy of the hip and/or knee that does not respond to any conservative therapy or better alternative surgical treatment;
Surgical intervention for severe trauma, revision hip or knee arthroplasties, and/or Oncology indications.
Metastatic diseases

Type of Use (Select one or both, as applicable)
☑ Prescription Use (Part 21 CFR 801 Subpart D) ☐ Over-The-Counter Use (21 CFR 801 Subpart C)	☑ Prescription Use (Part 21 CFR 801 Subpart D)	☐ Over-The-Counter Use (21 CFR 801 Subpart C)
☑ Prescription Use (Part 21 CFR 801 Subpart D)
☐ Over-The-Counter Use (21 CFR 801 Subpart C)

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ડ. 510(k) Summary

5.1. Submitter

Onkos Surgical, Inc. 77 East Halsey Road Parsippany, NJ 07054 Phone: (551) 579-1081 Contact Person: Matthew Vernak Email: mvernak@onkossurgical.com

Date Prepared: 28-Jul-2021

5.2. Device

Name of Device:	ELEOS™ Limb Salvage System
Common Name:	Limb Salvage System
Classification Name:	21 CFR 888.3510, Prosthesis, Knee, Femorotibial, Constrained,Metal Polymer, Cemented21 CFR 888.3350, Prosthesis, Hip, Semi-Constrained,Metal/Polymer, Cemented21 CFR 888.3560, Knee joint patellofemorotibialpolymer/metal/polymer semi- constrained cemented prosthesis21 CFR 888.3358 Prosthesis, Hip, Semi-Constrained,Metal/Polymer, Porous, Uncemented21 CFR 888.3353, Prosthesis, Hip, Semi-Constrained,Metal/Ceramic/Polymer Cemented or Non-Porous, Uncemented
Regulatory Class:	II
Product Code(s):	KRO JDLJWH LPH LZO

Predicate Device 5.3.
ELEOS™ Limb Salvage System, Onkos Surgical, Inc., K161520 (Primary Predicate) Orthogenesis LPS System, DePuy, Inc., K003182 (Predicate)

ર્ડ 4. Device Description

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section, resurfacing femur, proximal tibia, patella, stem extension, and tibial wedges and augments. Instrumentation is provided non-sterile in surgical trays which are to be re-processed per validated instructions.

	RECONSTRUCTION APPLICATIONS
Components	ProximalFemur	Intercalary	DistalFemur	TotalFemur	ProximalTibia	HingedKnee
Femoral head	✓			✓
Proximal Femur	✓			✓
Female Stem		✓
Mid-Section	✓	✓	✓	✓	✓	✓
Segmental Stem	✓	✓	✓	✓	✓	✓
Distal Femur			✓	✓
Tibial Hinge Component			✓	✓	✓	✓
Axial Pin			✓	✓	✓	✓
Tibial Poly Spacer			✓	✓	✓	✓
Tibial Baseplate			✓	✓	✓	✓
Male-Male Midsection				✓
Resurfacing Femur					✓	✓
Proximal Tibia					✓	✓
Patella1			✓	✓	✓	✓
Wedges and Augments1			✓	✓	✓	✓
Stem Extensions1			✓	✓	✓	✓

1 – These implants are optional for each procedure. The surgeon shall use their medical judgement to determine if these implants are necessary based on factor such as patient bone quality, joint stability, and pathology.

The implants are single use devices.

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5.5. Indications for Use

The ELEOS™ Limb Salvage System is indicated for resection and replacement of the proximal femur, intercalary portion of the femur, total femur, and proximal tibia in skeletally mature patients with the following conditions:

1. Non-inflammatory degenerative joint disease such as osteoarthritis, traumatic arthritis, avascular necrosis, ankylosis, protrusion acetabuli, and painful hip dysplasia;
1. Inflammatory degenerative joint disease such as rheumatoid arthritis;
1. Correction of functional deformity
1. Revision procedures where other treatments or devices have failed; and,
1. Treatment of fractures that are unmanageable using other techniques.

1. Patients suffering from severe arthropathy of the hip and/or knee that does not respond to any conservative therapy or better alternative surgical treatment;
1. Surgical intervention for severe trauma, revision hip or knee arthroplasties, and/or Oncology indications.
1. Metastatic diseases

Comparison of Technological Characteristics with the Predicate Device 5.6.

The subject device incorporates a new indication for use, intercalary replacement. This is in addition to the current indications of the primary predicate ELEOS Limb Salvage System and consistent with the indications of the predicate DePuy LPS System. The subject device is a line extension to the primary predicate device and can be used interchangeably with existing system components.

The design of the female stem will utilize the same material, segmental taper, cement flutes, and length as the primary predicate, ELEOS Limb Salvage System.

5.7. Performance Data

A risk-based evaluation of the subject and predicate device determined that the addition of the female stem to complete an intercalary replacement does not raise new concerns with respect to safety and/or effectiveness of the device. This is demonstrated by no new or increased risks related to loosening, subsidence, fatigue, dissociation, and/or fretting corrosion compared to the primary predicate device. Therefore, additional performance testing was not required to support this submission.

5.8 Clinical Data

Clinical data was not deemed necessary for the subject device.

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Conclusions 5.9

Based on the test results and supporting documentation provided in this premarket notification, the subject ELEOS Limb Salvage System is substantially equivalent to the primary predicate, ELEOS Limb Salvage System, and predicate, Orthogenesis LPS System. The content in this premarket notification demonstrates that:

. any differences do not raise new questions of safety and effectiveness;
and the proposed device is at least as safe and effective as the legally marketed predicate ● devices.

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.