Help With Broken Humerus Rehab

I suffered a 2/3 distal spiral fracture of my left humerus while arm wrestling in May 2007. I have a plate and 12 screws holding it together. My prescribed rehab was basically a tennis elbow routine with various stretches and forearm strengthening exercises.

While bench pressing with dumbbells or BB my ulnar nerve moves causing a sensation similar to hitting my funny bone, but not painful. My surgeon said not to worry; don’t push it with heavy weights but keep working out. I have worked my way up to 40 lb dumbbells but my elbow joint feels very unstable.

Does anyone here have any advice you can give me? I would be willing to travel to see a very good physical therapist as I am also having moderate to severe wrist pain that resulted from my wrist slamming into the table when my arm broke. I would like to avoid another surgery at all costs. Any help is greatly appreciated.