Agency classClass IIOur severity:Moderate FDA (Devices)·Z-1256-2014·Announced 2014-03-26

Zimmer Recalls Natural-Knee II Constrained Knee System Tibia Components

Zimmer, Inc. is recalling 3,638 units of Natural-Knee II Constrained Knee System tibia components due to discoloration caused by premature oxidation.

The agency’s classification

FDA (Devices): Class II

Class II is a situation in which use of or exposure to a violative product may cause temporary or medically reversible adverse health consequences, or where the probability of serious adverse health consequences is remote.

This is the agency’s own classification, taken from its notice. The severity score below is our assessment, not the agency’s. How recall classes work

What this means for you

Our assessment, not the agency’s: severity 2/5 (Moderate).

Minor labeling or packaging issue, or a voluntary precautionary recall. Risk of harm is low but real — follow the manufacturer's instructions.

Our severity reasoning: The recall is classified as FDA Class II. The hazard involves discoloration due to oxidation, which is a quality defect without reported injuries or illnesses, fitting the criteria for a moderate severity recall.

Plain-English summary

Zimmer, Inc. is recalling 3,638 units of the Natural-Knee II Constrained Knee System tibia components. The affected items include various sizes and configurations of the NKII CCK TIB INS, distributed nationwide in the United States and in several international markets including Canada, Australia, India, and various European countries.

The recall was initiated after a complaint was received regarding a discolored All Poly Tibia. Root cause analysis determined that the discoloration was the result of free radical oxidation. This oxidation process was advanced prematurely because the machined components were stored in transparent containers exposed to artificial light for six years prior to inert packaging and sterilization.

The source text does not specify instructions for consumers or healthcare providers on how to handle the recalled devices, nor does it report any specific illnesses or injuries associated with the use of these components.

The recalled product

Product: Natural-Knee¿ II Constrained Knee System NKII CCK TIB INS SZ00/0-L NKII CCK TIB INS SZ1/2-LF NKII CCK TIB INS SZ3-5 -L NKII CCK TIB INS SZ00/0-R NKII CCK TIB INS SZ3-5 -R NKII CCK TIB INS SZ1/2-LF NKII CCK TIB INS SZ3-5 -L NKII CCK TIB INS SZ00/0-R NKII CCK TIB INS…
Manufacturer: Zimmer, Inc.
Category: Medical Device — Orthopedic Implant
Hazard: material-degradation
discoloration
Affected units: 3,638

Distribution

Distributed nationwide across the United States.

The notice also names 32 states specifically:

Part of a larger recall action

This product is one of 15 recalled by Zimmer, Inc. under a single FDA (Devices) recall action. The agency files each product separately, so the size of the action is not visible from this page alone.

See all 15 products in this recall →

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Same hazard · material degradation