KEYSTONE HIP SYSTEM CALCAR REPLACEMENT BODY AND BUILD UP by ENCORE ORTHOPEDICS, INC.

The indications for use of the total hip replacement prosthesis include: noninflammatory degenerative joint disease including osteoarthritis and avascular necrosis; rheumatoid arthritis; correction of functional deformity; revision procedures where other treatments or devices have failed; and treatment of nonunion, femoral neck and trochanteric fractures of the proximal femur with head involvement, which is unmanageable using other techniques. This stem is to be pressfit.

Device Description

The Keystone® Hip System is available in a variety of proximal bodies and distal stem diameter and length configurations. The proximal body and stem are attached via a Morse type taper junction with an axially loading screw providing secondary attachment. The bodies, stems, and fixation screws were cleared on 510(k) K000521. All components are manufactured from titanium alloy (Ti-6A1-4V) that conforms to ASTM F136 with a porous coating that conforms to ASTM 1854-98 applied to the proximal body.

The additional components that are the subject of this Special 510(k) submission are the calcar replacement bodies and calcar build-ups.

The calcar replacement bodies are to be used either with or without a calcar build-up. During revision surgery or treatment of intertrochanteric fractures, the medial calcar bone is often deficient. This implant allows the surgeon to rest the calcar platform of the stem on the remaining medial bone. The modular build-up is available in a +15 and +30mm height for each size stem. The build-up is attached to the stem using an attachment screw. The modular buildups are fabricated from wrought titanium-aluminum-vanadium alloy (Ti-6Al-4V) conforming to ASTM F136.

The attachment screw is used to attach the calcar build-up to the calcar replacement bodies. The attachment screw is fabricated from wrought titanium-aluminum-vanadium alloy (Ti-6Al-4V) conforming to ASTM F136.

AI/ML Overview

This document is a 510(k) premarket notification for the Keystone® Hip System Calcar Replacement Body and Build-up. It states that the device is substantially equivalent to legally marketed predicate devices. This type of submission relies on demonstrating equivalence rather than conducting new clinical trials to prove efficacy and safety. Therefore, the document does not contain the detailed information requested regarding acceptance criteria and a study proving the device meets those criteria in the way a de novo or PMA submission might.

Specifically, for the Keystone® Hip System Calcar Replacement Body and Build-up, the FDA determined substantial equivalence based on comparable features to predicate devices, including "same materials, design and indications." This implies that the acceptance criteria for this 510(k) were primarily satisfied by demonstrating that the new components perform similarly to previously cleared devices under similar conditions and for similar intended uses.

Given this context, I cannot provide the specific details for many of your requested points because they are not typically part of a 510(k) summary demonstrating substantial equivalence for an orthopedic implant of this nature.

Here's an attempt to answer based on the provided text, recognizing the limitations:

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

Based on the 510(k) summary, the acceptance criteria implicitly relate to demonstrating substantial equivalence to predicate devices. This means the new components must:

Use the same materials (Titanium alloy (Ti-6A1-4V) conforming to ASTM F136 with a porous coating conforming to ASTM 1854-98).
Have a similar design as the predicate and the existing Keystone® Hip System.
Be intended for the same indications as the predicate (total hip arthroplasty for specific conditions like osteoarthritis, avascular necrosis, rheumatoid arthritis, etc., and revision arthroplasty).
The mechanical properties of the attachment mechanism (Morse type taper junction with an axially loading screw) are implied to be robust and already cleared with the K000521 submission.

The "reported device performance" in this context is the FDA's determination that these new components do meet these implicit criteria for substantial equivalence. No numerical performance metrics are stated.

Acceptance Criteria (Implicit from Substantial Equivalence)	Reported Device Performance (FDA's Determination)
Materials: Conforming to specified ASTM standards.	Device utilizes specified materials.
Design: Similar to predicate devices and existing system.	Design is considered similar.
Intended Use: Matching predicate indications.	Device is indicated for the same uses.
Performance (general): Safe and effective for intended use as per predicate.	Deemed substantially equivalent to predicate devices, implying safety and effectiveness.

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. This 510(k) relies on substantial equivalence to predicate devices, not on a new clinical study with a test set of data.

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 for a 510(k) substantial equivalence submission for this type of device. There was no "test set" requiring expert ground truth in the context of efficacy for the new components.

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

Not applicable. See point 3.

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 device is a hip implant, not an AI-assisted diagnostic or therapeutic tool. No MRMC study was performed.

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

Not applicable. See point 5.

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

For a 510(k) substantial equivalence determination for an implant, the "ground truth" is typically established by:

Regulatory Precedent: The FDA has previously cleared similar devices (predicates) based on their safety and effectiveness.
Material Standards: Adherence to recognized national and international standards (e.g., ASTM F136, ASTM 1854-98) for materials.
Bench Testing: Mechanical testing (which is not detailed in this summary but is typically part of a 510(k) submission for implants) to demonstrate that the new components meet performance specifications similar to the predicate.
Clinical Experience: The established clinical history and performance of the predicate devices.

8. The sample size for the training set

Not applicable. This device is a hip implant, not an AI or machine learning system that requires a "training set."

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

Not applicable. See point 8.

Summary

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Summary of Safety and Effectiveness

Encore Orthopedics®, Inc. 9800 Metric Blvd Austin, TX 78758 512-832-9500

FEB 1 1 2002

Trade Name: Keystone® Hip System Calcar Replacement Body and Build-up

Common Name: Cementless hip stem

Classification Name: Hip joint metal/polymer/metal semi-constrained porous coated uncemented prosthesis

Description: The Keystone® Hip System is available in a variety of proximal bodies and distal stem diameter and length configurations. The proximal body and stem are attached via a Morse type taper junction with an axially loading screw providing secondary attachment. The bodies, stems, and fixation screws were cleared on 510(k) K000521. All components are manufactured from titanium alloy (Ti-6A1-4V) that conforms to ASTM F136 with a porous coating that conforms to ASTM 1854-98 applied to the proximal body.

The additional components that are the subject of this Special 510(k) submission are the calcar replacement bodies and calcar build-ups.

Intended Use: The Keystone® Hip System is intended for treatment of patients who are candidates for total hip arthroplasty because the natural femoral head and neck have been affected by osteoarthritis, inflammatory arthritis, traumatic arthritis, rheumatoid arthritis, avascular necrosis or femoral neck fracture, and revision arthroplasty.

Comparable Features to Predicate Device(s): Features comparable to predicate devices include same materials, design and indications.

KOZO170 VI

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Image /page/1/Picture/1 description: The image is a seal for the Department of Health & Human Services - USA. The seal is circular and contains the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter. In the center of the seal is an abstract image of a bird-like figure.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

FEB 1 1 2002

Ms. Joanna Droege Regulatory/QA Engineer Encore Medical Corporation 9800 Metric Boulevard Austin, Texas 78758

Re: K020170

Trade Name: Keystone® Hip System Calar Replacement Body and Build-up Regulation Number: 21 CFR 888.3358 Regulation Name: Hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis Regulatory Class: Class II Product Code: LPH

Dated: January 14, 2002 Received: January 17, 2002

Dear Ms. Droege:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to 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, (Trefore, 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, oontons provisions or actice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to such 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 or any I with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set 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.

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Page 2 - Ms. Joanna Droege

This letter will allow you to begin marketing your device as described in your Section 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 21 CFR Part 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4659. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html.

Sincerely yours,

Miriam C. Provost

for Celia M. Witten, Ph.D., M.D. Director Division of General, Restorative and Neurological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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170

510(k) Number (if known):

Keystone® Hip System Calcar Replacement Body and Build-up Device Name: __

Indications For Use:

Keystone® Hip System Indications For Use

The indications for use of the total hip replacement prosthesis include: noninflammatory degenerative joint disease including osteoarthritis and avascular necrosis; theumatoid arthritis; correction of functional deformity; revision procedures where other treatments or devices have failed; and treatment of nonunion, femoral neck and trochanteric fractures of the proximal femur with head involvement, which is unmanageable using other techniques. This stem is to be pressfit.

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

Prescription Use _> (per 21 CFR 801.109) OR

Over-The-Counter Use _________________________________________________________________________________________________________________________________________________________

(Optional Format 1-2-96)_

Muriam C. Provost

(Division Sign-Off) Division of General, Restorative and Neurological Devices

510(k) Number_KO2_0170

OK
II

SKHS

Regulation Number and Section

§ 888.3358 Hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis.

(a)
Identification. A hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis is a device intended to be implanted to replace a hip 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 has a femoral component made of a cobalt-chromium-molybdenum (Co-Cr-Mo) alloy or a titanium-aluminum-vanadium (Ti-6Al-4V) alloy and an acetabular component composed of an ultra-high molecular weight polyethylene articulating bearing surface fixed in a metal shell made of Co-Cr-Mo or Ti-6Al-4V. The femoral stem and acetabular shell have a porous coating made of, in the case of Co-Cr-Mo substrates, beads of the same alloy, and in the case of Ti-6Al-4V substrates, fibers of commercially pure titanium or Ti-6Al-4V alloy. The porous coating has a volume porosity between 30 and 70 percent, an average pore size between 100 and 1,000 microns, interconnecting porosity, and a porous coating thickness between 500 and 1,500 microns. The generic type of device has a design to achieve biological fixation to bone without the use of bone cement.(b)
Classification. Class II.