The St Helens-born prop, who has joined the Rhinos from Hunslet, is facing a six-month lay-off after undergoing surgery this week.
Leeds coach Brian McDermott said: "We are all desperately disappointed for Andy, especially at the start of his time at the club.
"However, the six months will not be wasted time for him. Instead he will have a full programme of rehabilitation from the conditioning staff and we will get him fully up to speed so he is ready for the step up to Super League. "
- Sports & Recreation