Ugh, that hurts my knees just thinking about it. We jump an otter where I am too and when we are on jump run I just stand up and bend over a little. I could never get on my knees. I can't even do that in church anymore. When I was a student I told my instructor I couldn't do the kneeling thing and he told me that was fine to just stand up, so that is what I do all the time now. I don't think I could do Cessna jumps anymore either. Try standing up, it's much easier on the knees. I also wear braces and that just makes moving around even more difficult. I've tried the "butt landing" and I just prefer a good PLF. As long as my knees are bent when I land I know I'll be fine. You just have to go with what works best for you.
As far as the tredmill goes... I have been at lots of skydiver parties where there was a treadmill in the house. From my experience tredmills and skydivers don't mix. If there is a tred mill in the house, someone is gonna get hurt! After a while, inevitably the damed thing gets turned off by the most adult supervisors! The last incident I recall was playing around with the volume button, trying to make people fall, or rather trying to stay upright. Then when one chick was sitting on the thing sideways eating a snack on a plate, someone snuck up and turned it on full speed! She went flying off the end and got stuck with the thing spinning under her spine. She got a big bruise and a tremendous surface burn. I'm sure it wasn't funnt to her later after the pot and booze wore off, but it was pretty funy at the time to her and everyone else in the room. The whole place erupted! Guess you had to be there! Again, after that, the tred mill got unplugged! Aren't skydivers a hoot! Tink!
I'm late to this thread, but I wanted to add my own experience with a missing acl. Mine was missing for probably three years, I lived fine without it for QUITE a while until one night I was at a concert hopped up to jump with the crowd and things changed. It wasn't a big hop, I wasn't pushed to have to react sideways with landing- my point is it wasn't much to cause me significant pain and further my problems with my knee.
After that, the knee would seem to pop out of place, my leg would go tingly and I couldn't put weight on it. Walking 100 yards to the pop machine would make it "pop" so I decided to see the doctor. It was a quick visit as my knee would unnaturally bend and surgery was scheduled shortly after. I had lived with the missing acl for so long I had torn my cartlidge- in a bucket tear- and that was what was causing me pain catching in the joint. They ended up taking out a lot of cartlidge in my knee while using another tendon from the back of my leg to fix the acl. My second point- waiting to get it fixed isn't a great idea because it won't fix itself and you're only causing more damage.
I now have a descent acl and I'm back to skydiving. Surgery was in October and I've made 4 careful jumps in the last few weeks. I've also been left with bursitis and the outlook of premature arthritis in my knee because it's missing so much of the cartlidge.
Jump with a brace, and go see a good pt to get some excersices to stregthen your leg (it will help now, and for a quick return after surgery).
I can't quite agree with the idea that all complete acl tears have to be replaced. The human body is an amazing thing and we have several ligaments and tendons that compensate for a missing acl. I'm in the gym four times a week making sure my hamstrings, quads, and calf muscles stay in shape for just that reason. Premature arthritis is sometimes inevitable with an injury sever enough to rupture your acl. I've torn out both of mine. One I had replaced and one not. The one I had replaced is going on about 8 years now and I have terrible arthritis in that knee. The other one has been about a year and it feels great. But I have no illusions, it will be full of arthritis in a few years too. ACL replacement wouldn't have avoided that for me. Another factor is age. If your young they usually do replace your ACL for all the reasons you mentioned. But for some of us total knee replacement is a very near future reality and replacing an ACL won't prevent that. I skydive with braces on both legs, spend lots of time in the gym, and pray God gives me at least 10 more good years on these knees!
I guess it all boils down to individual circumstances and I'm glad you were able to get yours fixed and it works better for you. Learn how to do good PLF's. They can really save the knees in a bad landing situation.