Cowan, who jetted out two weeks ago, has returned optimistic his problems have been remedied.
Speaking to Cats TV's nib Medical Room, club physio Mike Snelling said the operation was very successful.
"We sought an opinion overseas from a world expert and it was very successful," Snelling said.
"He had a little muscle problem near his Achilles that we've addressed.
"From the minute that he came out of surgery he felt much better, which is a real positive, and he's got a big smile on his face.
"His rehab's going to take a few weeks obviously, but we anticipate that we'll see him playing a fair bit this year.
To see the full nib Medical Report click the video above
