Pain and weakness of the wrist joint not improved by conservative treatment .
Instability of the ulnar head with x-ray evidence of dorsal subluxation and erosive . changes
Failed ulnar head resection .

Device Description

The Ascension® MUH implant is a single-use, two-component, modular prosthesis designed for replacement of the ulnar head. Components will be available in three head sizes, and nine stem sizes which are assembled by means of a taper connection. Device components are made from cobalt chromium alloy meeting ASTM F1537 and titanium Ti6A14V ELI meeting ASTM F136, the same materials used to fabricate other ulnar head prostheses that have market clearance for sale in the United States.

AI/ML Overview

The provided text is a 510(k) Summary for the Ascension® MUH ulnar head prosthesis, which is a medical device. This document focuses on demonstrating substantial equivalence to a predicate device rather than presenting a study proving the device meets specific performance acceptance criteria through clinical or analytical trials.

Therefore, the document does not contain the information requested regarding acceptance criteria and a study proving the device meets them, as typically understood for a novel device. The "study" here is a comparison to a legally marketed predicate device.

Here's an analysis of why the requested information is absent based on the provided text:

Acceptance Criteria and Reported Device Performance: These are not provided because the submission is for substantial equivalence to a predicate device, not for demonstrating performance against defined metrics for a novel technology. The "performance" being assessed is the equivalent design, materials, and intended use to the predicate.
Sample size and data provenance: No test set or data provenance is mentioned because this is a medical device comparison submission, not a study involving patient data or a test set in the conventional sense of a clinical trial or algorithm validation.
Number of experts and qualifications: Not applicable. Ground truth establishment is not relevant for this type of submission focused on device comparison rather than diagnostic accuracy or clinical outcomes.
Adjudication method: Not applicable.
Multi Reader Multi Case (MRMC) comparative effectiveness study: Not applicable. This type of study is relevant for diagnostic devices or AI algorithms that assist human readers, not for a prosthetic device submission based on substantial equivalence.
Standalone (algorithm-only) performance: Not applicable, as this is a physical prosthetic device, not an algorithm.
Type of ground truth used: Not applicable, as there's no diagnostic or predictive component being evaluated.
Sample size for the training set: Not applicable, as this is a physical medical device, not an AI model.
How the ground truth for the training set was established: Not applicable.

Summary of Device Comparison (used as the "study" for substantial equivalence):

The "study" presented is a comparison of features between the Ascension® MUH implant and the predicate device, Avanta Orthopaedics, Inc., Ulnar Head Implant (K010786).

Acceptance Criteria (Implicit for Substantial Equivalence):
The implicit acceptance criteria for substantial equivalence, as demonstrated by the comparison table, are that the subject device (Ascension® MUH) must have:

Same Indications For Use: Confirmed, as stated in the text.
Same/Similar Design: Confirmed (two-piece modular implant, taper connection, stem in medullary canal, hemi articulation).
Same/Similar Materials: Confirmed (cobalt chromium for head, titanium for stem – a different grade of titanium for the stem, but considered acceptable for substantial equivalence to CpTi).
Same/Similar Performance Characteristics: Implied by the above similarities and the lack of new questions of safety or effectiveness.
No new questions of safety or effectiveness: Implied by the FDA's determination of substantial equivalence.

Reported Device "Performance" (Comparison to Predicate):

Below is a table summarizing the comparison, which serves as the "proof" for substantial equivalence.

Comparison Feature	Ascension® MUH (Subject Device)	Avanta Ulnar Head Implant (Predicate Device)
Design	Two-piece modular implant	Two-piece modular implant
Material (Head)	ASTM F1537 cobalt chromium	ASTM F1537 cobalt chromium
Material (Stem)	ASTM F136 Ti6Al4V ELI	CpTi
Assembly	Taper connection	Taper connection
Fixation	Stem in medullary canal	Stem in medullary canal
Articulation	Hemi	Hemi
Use	Single use only, surgical implantation longer than 30 days	Single use only, surgical implantation longer than 30 days
Sterilization by user	Resterilization of device is not recommended.	Resterilization of device is not recommended.
Packaging	Double barrier assembly in paperboard box	Double barrier assembly in paperboard box
Accessories	Sterilizable instrumentation available separately	Sterilizable instrumentation available separately
Stem surface finish	Roughened	Roughened
Available sizes	Three heads (3 diameters), Nine stems	Three heads (3 diameters), Six stems
Indications for Use	Identical to predicate device	See "Indications For Use" section
Functional Equivalence	Functionally identical	(Implied)
Sizing	Comparably sized (more stem options)	(Implied)

Conclusion from the "Study":

The 510(k) summary explicitly states: "The Ascension® MUH is functionally identical, comparably sized, and has a similar design as compared to the Avanta Ulnar Head Implant. Individual components for the subject and predicate device are provided sterile in individual packages. The Ascension® MUH shares identical indications for use with the predicate device, and is fabricated from the same material as the predicate device. Therefore, the Ascension® MUH is substantially equivalent to the predicate device."

In summary, the provided document does not describe a performance study with acceptance criteria in the typical sense of evaluating a novel device's efficacy or safety against specific metrics. Instead, it presents a comparison to a predicate device to establish substantial equivalence based on design, materials, and intended use.

Summary

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K052137 p½
Page 26 of 86

510(k) SUMMARY

SUBMITTER NAME:	Ascension Orthopedics, Inc.8700 Cameron Road, C-100Austin, TX 78754-3832
510(k) CONTACT:	Glen NeallyPhone: (512) 836-5001
TRADE NAME:	Ascension® MUH
COMMON NAME:	ulnar head prosthesis
CLASSIFICATION:	21 CFR §888.3810
PRODUCT CODE:	87 KXE
PANEL:	Orthopedic

PREDICATE DEVICE:

Avanta Orthopaedics, Inc., Ulnar Head Implant (K010786)

DEVICE DESCRIPTION:

INTENDED USE:

The Ascension® MUH implant is intended for replacement of the distal radioulnar joint:

Replacement of the distal ulnar head for rheumatoid, degenerative, or post-traumatic arthritis presenting the following:

. Pain and weakness of the wrist joint not improved by conservative treatment
Instability of the ulnar head with x-ray evidence of dorsal subluxation and erosive . changes
Failed ulnar head resection .

BASIS OF SUBSTANTIAL EQUIVALENCE:

A comparison of identical materials and nearly identical design features, demonstrate that the Ascension® MUH is substantially equivalent to the predicate device as indicated in the chart below:

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ComparisonFeature	Ascension Modular Ulnar Head	Avanta Ulnar Head Implant
Design	Two-piece modular implant	Two-piece modular implant
Material (Head)	ASTM F1537 cobalt chromium	ASTM F1537 cobalt chromium
Material (Stem)	ASTM F136 Ti6Al4V ELI	CpTi
Assembly	Taper connection	Taper connection
Fixation	Stem in medullary canal	Stem in medullary canal
Articulation	Hemi	Hemi
Use	Single use only, surgical implantation longer than 30 days	Single use only, surgical implantation longer than 30 days
Sterilization byuser	Resterilization of device is not recommended.	Resterilization of device is not recommended.
Packaging	Double barrier assembly in paperboard box	Double barrier assembly in paperboard box
Accessories	Sterilizable instrumentation is available separately (not provided sterile).	Sterilizable instrumentation is available separately (not provided sterile).
Stem surfacefinish	Roughened	Roughened
Available sizes	Three heads:(3 diameters)Nine stems	Three heads:(3 diameters)Six stems

Similarities of the Ascension® MUH implant and the Avanta Ulnar Head Implant include: Both devices have the same indications for use; Both devices are made of the same industry standard materials; No new materials are introduced in either product; Both devices are placed into the intramedullary canal of the distal end of the ulna; Both devices are a hemi articulation; Both devices are intended for surgical implantation longer than 30 days: Both devices are intended for single use only.

Summary:

The Ascension® MUH is functionally identical, comparably sized, and has a similar design as compared to the Avanta Ulnar Head Implant. Individual components for the subject and predicate device are provided sterile in individual packages. The Ascension® MUH shares identical indications for use with the predicate device, and is fabricated from the same material as the predicate device. Therefore, the Ascension® MUH is substantially equivalent to the predicate device.

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Image /page/2/Picture/1 description: The image shows the logo for the U.S. Department of Health and Human Services. The logo features a stylized depiction of an eagle with three heads, representing the department's commitment to health, human services, and well-being. The eagle is positioned to the right of the text, which is arranged in a circular pattern around the logo. The text reads "DEPARTMENT OF HEALTH AND HUMAN SERVICES. USA".

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

NOV - 3 2005

Glen Neally Director of QA/RA Ascension Orthopedics, Inc. 8700 Cameron Road, Suite 100 Austin, Texas 78754-3832

Re: K052137

Trade/Device Name: Ascension® MUH Regulation Number: 21 CFR 888.3810 Regulation Name: Wrist joint ulnar (hemi-wrist) polymer prosthesis Regulatory Class: II Product Code: KXE Dated: July 22, 2005 Received: August 5, 2005

Dear Mr. Neally:

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.

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 comply 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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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), please contact the Office of Compliance at (240) 276-0120. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). 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) 443-6597 or at its Internet address http://www.fda.gov/cdrh/industry/support/index.html.

Sincerely yours.

Mark N. Melkerson

Acting Director Division of General, Restorative and Neurological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Indications For Use

510(K) Number: K052137

Ascension® MUH Device Name:

Indications for Use:

The Ascension® MUH is intended for replacement of the distal radioulnar joint:

Replacement of the distal ulnar head for rheumatoid, degenerative, or post-traumatic arthritis presenting the following:

Pain and weakness of the wrist joint not improved by conservative treatment .
Instability of the ulnar head with x-ray evidence of dorsal subluxation and erosive . changes
Failed ulnar head resection .

Contraindications

Malunited forearm fractures that preclude stabalization of the ulnar head during . pronation/supination
. Tendon, ligament, or distal radioulnar joint which cannot provide adequate support or fixation for the prostheses
Inadequate skin or musculotendinous system .
Growing patients with open epiphyses .
Previous open fracture or infection in or around the joint . Known sensitivity to materials used in this device

X Prescription Use (Part 21 CFR 801Subpart B) Over-The-Counter Use (Part 21 CFR 801Subpart C)

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

(Division Sign-Off) (Division of General, Restorations of CDRH, Office of Device Evaluation (ODE) and Neurological Devices

510(k) Number K052137

Regulation Number and Section

§ 888.3810 Wrist joint ulnar (hemi-wrist) polymer prosthesis.

(a)
Identification. A wrist joint ulnar (hemi-wrist) polymer prosthesis is a mushroom-shaped device made of a medical grade silicone elastomer or ultra-high molecular weight polyethylene intended to be implanted into the intramedullary canal of the bone and held in place by a suture. Its purpose is to cover the resected end of the distal ulna to control bone overgrowth and to provide an articular surface for the radius and carpus.(b)
Classification. Class II.