The bones on either side move closer together, sometimes leading to bone spurs
and pinched nerves.
One of the other "reversers" Andrew Flintoff underwent the knife to fix a bone spur
problem in February and took nearly three months to recover.
She stated that prior to developing the bone spur
in 1997, while working at the hospital, she had not experienced any other problems with her feet.
The bone spur
was discovered when a second set of X-rays was taken after Napoli initially injured himself July 1 at Baltimore.
Gloucester have thrust Rob Thirlby into the side after Olly Morgan suffered a fractured jaw and Jon Goodridge underwent shoulder surgery to remove a bone spur
He underwent an hour-long operation on December 7 during which a piece of floating bone was removed, a bone spur
was removed and a tear to the cartilage was repaired.
The Glamorgan seamer is targeting the second half of England's winter programme after being forced to miss the pre-Christmas tour to Pakistan to undergo surgery on an ankle bone spur
They would have been encouraged by Flintoff's 17 off 23 balls on his senior comeback for Lancashire in their totesport league defeat by Middlesex at Lord's on Sunday, his first outing since having a bone spur
removed from his left ankle following an operation on January 30.
The Lancashire all-rounder returned home early from the tour of South Africa to have surgery on a troublesome bone spur
on his left ankle in order for him to be ready to face Australia this summer.
The 27-year-old has been troubled by a bone spur
for some time and England felt it was best to sacrifice his involvement in the seven-match one-day series to be fit for the Ashes in the summer.
Flintoff is to see a specialist on Friday to arrange a date to undergo the operation on a bone spur
There are fears he will require surgery to repair the bone spur