Exercises to support the AC joint?

Last February I was involved in a collision with a car (me on my bike). My main injury was a fractured right femur. That's coming along nicely, thanks to the addition of some internal titanium scaffolding. I've been back on my bike for quite awhile, have pretty much full range of motion in my knee and hip, and have recovered much of my leg strength. At times I can even jog short distances with little or no discomfort. Secondary to that I also dislocated my left AC joint. At the time, treating it seemed relatively unimportant as I needed both arms for crutches for several weeks, and my physical therapy focused on my leg. I haven't been in the pool in a long while. I tried a couple times after I was mobile, but decided I wasn't ready, and went so far as to give up my pool membership. My AC joint still pops out in a number of situations, so I think I might need more than more r&r. I did get some attention from my physical therapist and do a couple exercises pretty regularly (standard horizontal rotation, and rolling my scapulae back and down), but wonder if there is more I could be doing. I'm coming up on my one-year follow-up, and plan to discuss options with my doctor. In anticipation of possible surgery, or just continued rehab, I'm wondering what other exercises I could do to improve strength around the joint.