Synthes, Inc., shareholders, meeting at the company's headquarters in Solothurn, Switzerland, voted to approve the proposal by Johnson & Johnson to take over Synthes for $21.3 billion in cash and stock.
"The shareholders approved the proposal to adopt the agreement and plan of merger as outlined in the invitation," Synthes said in a statement.
Synthes has facilities and a U.S. headquarters in Chester County.
The companies hope to close the deal in the first half of 2012.
The European Union is reviewing the deal to examine the anti-trust effects on the market for screws, plates and other devices to fix bones broken through trauma or wear and tear. The EU set a new deadline of April 2 to rule on the acquisition, which would be the largest in the history of J&J.