Why wont my hand fracture heal without surgery?

It can: Typically with hand fractures the question is no will it heal but in what position will it heal in. If the fracture is not in a good position your hand function will be compromised.

Most fracture "heal": The question is after it heals is the position adequate enough to function well, surgical decisions weigh the risk and outcome of surgery vs treating fractures non surgically. No matter what is chosen there are many decisions to be made to further qualify each path i.e. Surgery can mean many things and so can non surgical rx. When there is a nonunion/ .Healing may "need" surgery to heal.