The UFC released a statement addressing the situation Wednesday, one day after Brazilian news source Combate reported Aldo (25-1) had suffered a fractured rib while training in Rio de Janeiro.
According to UFC officials, the 28-year-old champion was re-examined Wednesday. It was determined the injury was not a fractured rib, clearing the way for Aldo to make his eighth title defense against McGregor (17-2) at UFC 189 in Las Vegas.
"In light of recent reports regarding the status of UFC featherweight champion Jose Aldo, UFC has received official medical confirmation from several doctors that Aldo did not suffer a broken rib," the statement read. "Following a review of the scans, it has been determined that the champion suffered a bone bruise to his rib and cartilage injury during training.
"With the news, Aldo has expressed that he has every intention of facing Conor McGregor at UFC 189."
Francisco Aguilar, chairman of the Nevada State Athletic Commission, told ESPN.com that the commission's physicians will thoroughly examine Aldo prior to the fight and will confirm the absence of a fractured rib independently.
"We have to," Aguilar said. "It's our duty and obligation to ensure a licensed fighter is healthy before competing. We're going to have our doctors independently evaluate the situation."
In the event Aldo is not fit to compete, the UFC has announced two-time title challenger Chad Mendes (17-2) would replace Aldo on the pay-per-view event, which will take place inside MGM Grand Garden Arena. Should that be the case, the UFC would award the winner of that fight an interim title.
Aldo is undefeated in the UFC. He hasn't lost in nearly a decade and currently is riding an 18-fight win streak. ESPN.com ranks Aldo the No. 2 pound-for-pound fighter in the world.
Fighting out of Dublin, McGregor also is unbeaten in the UFC. He has finished his past three fights via knockout.
The UFC has spent lavishly in promoting the Aldo-McGregor title fight. The company initiated its first world tour in March, hosting news conferences in Rio de Janeiro, Las Vegas, Los Angeles, Boston, New York, Toronto, London and Dublin.
Jose Aldo won't be stopped by rib injury
ESPN MMA columnist Brett Okamoto discusses Jose Aldo's bone bruise and its implications on his upcoming fight against Conor McGregor.