Some ideas

Hey People,
Maybe you can  help me with this problem. I was a big lifter back in the 70's and 80's blew my shoulder out with heavy bench presses. my dilema is that my son has been traning and doing well he is 16 6'2" and about 290-295. he just tore his ACL and had Menicus damage and will need surgery basically reconstructive. he is bummed and I want to know what basically would anyone reccomend he could do to keep in shape and as he rehabs for 9 mos.? He is working out at a local gym which is equipped quite well with Hammer Strength equipment. I can do the heavy stuff for Powerlifter but want to keep his interest up so he will be ready for a full return to his routine. Thanks!