At 31, he has just undergone his second knee operation.

Decades ago, those who had knee operations often spent weeks in a cast.

Later that year she underwent a knee operation but never returned to her old form.

And he has had to recover from two knee operations.

For the second year running he underwent a knee operation at the end of the season.

The knee operation was the fourth for the 35-year-old catcher.

Coming back from three knee operations also took its toll.

He played much of the 2003 season despite needing a knee operation.

Houston said he felt better than at any other time since his right knee operation on June 10.

In May 2011 he had to undergo a further knee operation.