It was thought that Aldo had suffered a broken rib during a training session on Tuesday, an injury that would have made the July 11 fight almost impossible to make.
However, after undergoing further checks it has been revealed that the current champion has suffered a bone bruise and cartilage damage.
As a result, the UFC have released a statement confirming that the highly-anticipated bout will go ahead as planned.
The statement read: "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. 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 this news, Aldo has expressed that he has every intention of facing Conor McGregor at UFC 189."
However, should Aldo not recover sufficiently to fight, the UFC have a backup plan.
"While Aldo has indicated that he will compete in Las Vegas on July 11, UFC has confirmed a contingency plan. No.1 featherweight contender Chad Mendes will face McGregor for the interim UFC featherweight championship in the event Aldo cannot compete," the organisation said.
"UFC remains committed to delivering the featherweight and the welterweight championship fights at UFC 189 during UFC International Fight Week in Las Vegas."
UFC chairman Dana White took to Twitter to reassure fans that all was well.
— Dana White (@danawhite) June 25, 2015