This last August my right shoulder dislocated in free-fall and let me tell you it was no fun especially because it was during a hop-and-pop from 4,500 ft. My arm was in excruciating pain and I couldn't even reach my hacky to deploy. I had to go straight to reserve during terminal. Once my reserve was open I couldn't raise my arm to reach my right toggle. Good thing it was a windy day because flaring was not an option. Once on the ground I couldn't do anything but just stand there in pain and needed help gathering my parachute. Spent the next 10 hours in the ER getting it put back in place. It's been 6 months now and I'm back in the air regularly. I had to have my hacky moved for a left hand deployment (I'm left handed anyway). I was wearing a neoprene brace for awhile as a little added security. I've avoided surgery so far but I'm sure it's in my future because since then I've avoided relative work in fear that it will get pulled out and most free-falls I've been in preying mantis form. My point is that's it's still possible to jump with a prior injury, but just know your limits and listen to your body. I'm giving it a year before I let anybody cut into me.