Long term effects of Shaken baby Syndrome

Ok, this may be a tough question to answer but I figured someone out there has been thru what I am going thru. I adopted my son when he was 4 years old and is now 11. He was bouncing baby boy who ultimately had 2 skull fractures before the age of 1 and was diagnosed shaken baby syndrome. When I adopted him I knew of his past but there were no real signs of anything. Now that he is 11, I am seeing signs of things that I don't want to let undiagnosed. I may be freaking out and being overly concerned but he's my son and I want whats best for him. 1. he has never been a strong child. Very weak to lift things but has the arm that throws 50 mph on the baseball mound. 2. can't do a basic pushup or pull up. 3. Has a very high metabolism and is ADHD. I've tried to limit the meds (as well as trigger foods) but those meds affect his eating and he is very skinny. 4. Small motor skills issues but a test last year said he was doing fine in those areas. (holding pencil - blocks ect) It has seemed to me that he has lost upper body stregnth over the past few years. Could his body be showing signs of the Shaken Baby syndrome all these years later? I did call the Dr. and started him on a supplement of Pediasure along with his regular breakfast and we were prescribed a visit to a physical therapist. Am I on the right track ? Any advise will be awesome !!!