Trainer Kevin Barry says the result of the surgery has been "nothing less than fantastic" with his charge back to the punching speed and power of 2016, a year which concluded with victory over American Andy Ruiz Jr to claim the vacant WBO belt.
Parker's orthopaedic surgeon Craig Ball says the procedure is a common one.
What was unusual with Parker, Dr Ball said, was the apparent speed with which he recovered.
"I think by losing that impingement pain that he would have, that will almost certainly give him a little bit more speed and probably power with his punch too," Dr Ball said.
"Because he's not having that pain limiting him every time he's trying to throw something".
-NZN
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