Hey Jeff I have Tandem jumped in February and I plan on doing my AFF course in May. I injured my back about six years ago and had my L3 vertabrae removed and replaced with a cage, they also fused L2 to L4 with two rods and four screws. I will not let this stop me for doing what I want, Right now I practice Jiu Jitsu and Kickboxing five days a week. Some times it hurts like Hell. I believe that you have to make the choice to enjoy life. So I would like to say to you give it a try and see what life has to offer