Left Arm cannot straighten since I was a baby

Good day,


I was born in a strange way, let me explain, I was a big baby, 12 pounds, and my mother is small (just over 5 feet). As I understand, I did not lie correctly in my mother's womb when I was born, thus nerves in my left shoulder got torn as the doctor struggled to get me out (normal birth, not cesarean etc...) , I think he yanked on my left arm to get me out. My parents then took me to a specialist, who implanted nerves from my left leg into my left shoulder, as I understand they had to take out 7 x 1cm pieces of nerve to get my shoulder working again.


The procedure seemed to go smoothly, I had feeling in my left arm and functioned relatively normally.


BUT, my left arm can't go 180 degrees straight, it stucks at just past 90 degrees. I also have a skewed rotation on my arm, I cannot rotate it anti clockwise more than I'd say 70 degrees, and can over rotate clockwise to almost turn my hand 180 degrees.


I also believe that my biceps are under developed in the process, cause it doesn't have it's full range.


I can use my arm normally, to type and have feeling in it like normal (except that my left elbow is a bit sensitive to pain(like someone punching it, haha) ) , but overworking it can cause cramps on my back and make my should feel a bit numb.


Is there anything surgery or physio could do about this? I've been living with this relatively normal for 33 years, it doesn't bother me at all, except when i feel it limits me a bit, or someone points it out, haha.


Sorry if I sound incomprehensible, English isn't my main language.