Synthes Holding AG (formerly Synthes-Stratec) is a multinational medical device manufacturer based in Solothurn, Switzerland and West Chester, Pennsylvania, United States.

[10] Stratec partially listed its shares on the SWX Swiss Exchange through an initial public offering six years later, while Synthes USA and Mathys remained in private hands.

[12] The third of the original AO/ASIF partner companies, Mathys, sold its osteosynthesis department to Synthes-Stratec in 2004,[13] although the firm's German division was divested to satisfy competition authorities.

In October 2010, Synthes and its subsidiary Norian both pleaded guilty to crimes relating to illegally implanting bone cement without FDA approval.

[17] In November 2010, Synthes acquired USA based privately owned surgical tools maker The Anspach Effort, Inc; the purchase price was not disclosed.

In 2009 the U.S. attorney in Philadelphia accused the company of illegally promoting a bone void filler for unapproved uses, running unauthorized clinical trials, and failing to properly report deaths and adverse events related to the product.

[21] Between 2002 and 2004, Synthes attempted to promote new uses for a product called Norian XR, a calcium phosphate bone void filler mixed with barium sulfate.

[22] These surgeries were allegedly performed despite a warning on the FDA-cleared label for Norian XR against this use, and in the face of serious medical concerns about the safety of the devices when used in the spine.

The research also showed, in a pig, that leakage of small amounts of Norian XR from the spine into the blood caused clots, which become lodged in the lungs.