# K973412: Natural-Knee II Constrained Knee System

- Pathway: 510(k) (Traditional)
- Applicant: Sulzer Orthopedics, Inc.
- Decided: Dec 8, 1997 after 90 days
- Product code: JWH (Prosthesis, Knee, Patellofemorotibial, Semi-Constrained, Cemented, Polymer/Metal/Polymer)
- Device class: 2
- Regulation: 21 CFR 888.3560
- Recalls of this device: 2 (0 Class I)
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026

## Lineage
No predicates in its family tree.
154 later devices descend from it; 4 cite it directly.
0 of 155 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- None. The FDA summary names its predicate without a number.
- (no number) Natural-Knee II System: named in the summary without a submission number
- (no number) Maxim Constrained Knee: named in the summary without a submission number
- (no number) Coordinate Revision Knee: named in the summary without a submission number

## Most influential descendants
- K060192: Apex Knee System (2006), 111 descendants of its own
- K073602: Modification to: Apex Knee System (2008), 72 descendants of its own
- K080842: Apex Knee System, Model KC-230XY, KC-240XY [ NO Holes, 2 Holes] (2008), 61 descendants of its own
- K131353: Comprehensive Reverse Shoulder - Titanium Glenosphere (2013), 60 descendants of its own
- K021740: Total Knee Cemented, Semi-Constrained (2002), 52 descendants of its own

## Recalls of this device
- Oct 2, 2014 · Class II · Z-1948-2015: Failed to meet established requirements for sterile barrier integrity due to a breach of the inner cavity. If the outer tray is compromised in addition to the inner tray a periprosthetic infection may
- Feb 25, 2014 · Class II · Z-1256-2014: A complaint was received for a discolored All Poly Tibia. Root cause analysis found that the discoloration was the result of free radical oxidation. The oxidation process was advanced prematurely as a

## Indications for use
The Natural-Knee™ II Constrained Knee System is intended use in the following diagnostic indications: 1. Patient conditions, including but not limited to, inflammatory degenerative joint disease (e.g., rheumatoid arthritis) and noninflammatory degenerative joint disease (e.g., osteoarthritis, avascular necrosis). 2. Correctable valgus-varus deformity and moderate flexion contracture. 3. Those patients with failed previous surgery where pain, deformity, or dysfunction persist. 4. Revision of previously failed knee arthroplasty. The Natural-Knee™ II Constrained Knee System is intended is intended only for use with bone cement. Uncemented use of the Natural-Knee™ II Constrained Knee System is considered to be investigational in the United States.

Source page: https://510kreport.com/device/K973412
Methodology: https://510kreport.com/methodology