# K223548: GMK Sphere & GMK SpheriKA Cementless

- Pathway: 510(k) (Traditional)
- Applicant: Medacta International S.A.
- Decided: Jan 20, 2023 after 56 days
- Product code: MBH (Prosthesis, Knee, Patello/Femorotibial, Semi-Constrained, Uncemented, Porous, Coated, Polymer/Metal/Polymer)
- Device class: 2
- Regulation: 21 CFR 888.3565
- Recalls of this device: none
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026

## Lineage
Longest line of descent: 14 generations back to K941847 (1994). 138 ancestors in all.
1 later device descends from it; 1 cites it directly.
0 of 139 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K091543: Legion Porous Plus HA Primary Femoral Components, Smith & Nephew, Inc. (2009) Summary page 4.
- K121416: GMK Sphere, Medacta International (2012) Summary page 4.
- K140826: GMK Sphere Extension, Medacta International (2014) Summary page 4.
- K211004: GMK Spherika Femurs and Fixed Tibial Trays Plus, Medacta International S.A. (2021) Summary page 4.
- K113550: Vanguard Complete Knee System, Biomet Manufacturing Corp (2012) Summary page 4.

## Most influential descendants
- K262057: GMK Extension (2026), 0 descendants of its own

## Indications for use
The GMK knee cemented prosthesis is designed for cemented application in total knee arthroplasty if there is evidence of sufficient sound bone to seat and support the components. The use of the cementless GMK femur is limited to cases in which the surgeon considers the bone quality to be sufficient for cementless applications. The GMK 3D Metal Tibial Baseplate is indicated for cementless or cemented application if there is evidence of sufficient sound bone to seat and support the components. This knee replacement system is indicated in the following cases: • Severely painful and/or disabled joint as a result of arthritis, traumatic arthritis, rheumatoid arthritis or polyarthritis • Collagen disorders, and avascular necrosis of the femoral condyle • Post traumatic loss of joint configuration • Primary implantation failure Tibial wedges cemented are to be attached to the tibial baseplate with both the fixing cylinders and bone cement. The screwed tibial augments are for screwed fixation to the tibial baseplate. In case a semi-constrained liner is used, an extension stem must be implanted both on the tibial and on the femoral components. In case a GMK Revision or GMK Sphere Revision tibial tray is used, an extension stem must be implanted. It is not possible to implant tibial wedges and extension stems with the GMK 3D Metal Tibial Baseplate. Limitations for use for GMK Sphere/GMK SpheriKA used with kinematic alignment GMK Sphere and GMK SpheriKA can be implanted in kinematic alignment. In this case, this knee replacement system is indicated for: • Severely painful and/or disabled joint as a result of arthritis, traumatic arthritis, rheumatoid arthritis or polyarthritis • Collagen disorders, and/or avascular necrosis of the femoral condyle • Moderate valgus, varus, or flexion deformities.

Source page: https://510kreport.com/device/K223548
Methodology: https://510kreport.com/methodology