your probably right. but since your breaks are in places where most bodyweight is held im assuming it would be worse than in my pinky.
when i was 14 i was hit by a car and fractured my pelvis, broke my femur and my jaw. i'm now 39 and i'm here to tell you, you WILL experience arthritis in the joints nearest the breaks. you don't have anythng much to worry about now, but when you reach your 30's you may have to start taking ibuprofen or naproxen or somethng to relieve pain. of course, since your break was in a small joint, you may not have much pain at all. i'm no doc, i am just guessing
When there is damage to a joint it does make it more prone to osteoarthritis in the future. Does he feel the surgery will lessen your chances?