Agreed with the swimming and the hand cycle thing. The latter looks completely dorky, but when a dislocated elbow kept me off the bike for about 6 months it really helped me rebuild strength in my arms.
Also, don't sweat the loss of fitness too much. Time off can be completely maddening when it isn't voluntary, but fitness doesn't just go away completely, especially not in 6 weeks. You might want to consider taking a little bit of time to just take it easy, rest, and relax so that you're ready to go at it hard again once you've healed. Good luck!