"Not to (sic) pretty, but its (sic) straight. Let it heal and start training. Amazing process. Sore as f**k but finally fixed after 33 years," Nash wrote in the caption.
He's thrilled to have finally taken steps to rid himself of pain, having posted previously about how much trouble his knee gives him.
Nash played college basketball for the University of Tennessee but quit the sport because of his knee issues.
He went on to star in World Championship Wrestling (WCW), where he began in 1990, as well as in the WWF and WWE.
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He made a name for himself playing Diesel — Shawn Michaels' bodyguard — and won the International Championship.
Nash teamed up with Hulk Hogan to form The New World Order in WCW in the mid-1990s and dominated before he split to form splinter group The Wolfpac alongside wrestlers like Randy Savage, Lex Luger and Sting.
Nash reunited with Hogan in 2002 in a return to the WWE but failed to make a mark in competition with people like "Stone Cold" Steve Austin and Dwayne "The Rock" Johnson and disbanded once more.
Nash left the promotion but made a comeback in 2011, attacking CM Punk at SummerSlam that year.