Agency classClass IIOur severity:Moderate FDA (Devices)·Z-1251-2014·Announced 2014-03-26

Zimmer Recalls Natural-Knee II Prosthesis Due to Discoloration

Zimmer, Inc. is recalling 3,638 units of Natural-Knee II knee prostheses because a component was found to be discolored due to 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, and the hazard involves a cosmetic defect (discoloration) with no reported injuries or illnesses, fitting the criteria for a moderate severity voluntary precautionary recall.

Plain-English summary

Zimmer, Inc. is recalling 3,638 units of the Natural-Knee II Unicompartmental Knee Prosthesis. The recall involves specific tibial insert components in sizes 1/2, 3/4, and 5/6 with thicknesses of 9mm, 11mm, and 13mm. The affected devices were distributed nationwide in the United States and in several international markets, including Canada, Australia, India, and various European and Asian countries.

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

The source text does not specify instructions for consumers or healthcare providers regarding the return or disposal of these devices, nor does it report any illnesses or injuries associated with the use of the affected prostheses.

The recalled product

Product: Natural-Knee¿ II - Unicompartmental Knee Prosthesis: CONG TIB INS SZ1/2 9MM UN CONG TIB INS SZ1/2 11MM U CONG TIB INS SZ1/2 13MM U CONG TIB INS SZ3/4 9MM UN CONG TIB INS SZ3/4 11MM U CONG TIB INS SZ3/4 13MM U CONG TIB INS SZ 5/6 9MM U CONG TIB INS SZ5/6 11MM U CONG TIB…
Manufacturer: Zimmer, Inc.
Category: Medical Device — Orthopedic Implant
Hazard: discoloration
oxidation
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 →

Same manufacturer · Zimmer, Inc.

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Same hazard · discoloration