Jorge Lorenzo underwent two hours of surgery in Barcelona overnight to repair the collarbone injured in his Dutch Grand Prix practice crash.
The MotoGP world champion flew to Spain for the operation as there was no space in Assen's local hospital.
Surgery was completed at 4am Spanish time, and was considered a success by Dr Michele Zasa from MotoGP's Clinica Mobile, who assisted Dr Joaquin Rodriguez with the operation at the Hospital General de Catalunya.
"The duration of the surgery was approximately two hours; the clinical course of post-operative has been regular," said Dr Zasa.
"Jorge sustained a displaced, complex fracture to the third medial of the left collarbone.
"It's been a challenging operation, apparently successful. We inserted a titanium plate and eight screws to secure the fragments of the collarbone.
"In the next few hours we will evaluate the progress of the patient and then we will be able to estimate how long the post-surgery rehabilitation will take."
Although MotoGP surgeon Dr Xavier Mir had initially suggested that Lorenzo's surgery would not be immediate in case other injuries became apparent, Yamaha team manager Wilco Zeelenberg said the Spaniard was keen to get the operation underway as quickly as possible.
"Following the medical check at the circuit's medical centre first and at the Assen hospital later, yesterday Jorge decided to be operated on as soon as possible," said Zeelenberg.
"Unfortunately no operation room was available in Assen due to some other very urgent life threatening operations that had much higher priority than Jorge's collarbone and therefore we flew to Barcelona."
Subscribe to Autosport Plus
Register for free