Not enough info. In general, your surgeon will perform surgery to ensure proper healing in circumstances where treating the fracture in a cast would result in a less favorable outcome. Getting the bone to heal is only one part of getting your hand to heal fully. There are other factors, such as the severity and location of the injury, as well as therapy, when needed that determine your final outcome.
6-8 weeks. Usually the pins/k-wires stay in for about 4 weeks. After that, you'll likely be pretty stiff. After a few weeks of occupational therapy, you should be pretty close to normal. Most people are fine in about 8 weeks.
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.