According to a recent update on radial head fractures published in The Journal of Hand Surgery, this type of fracture is the most common elbow fracture. Undisplaced (bones are not separated) fractures have the best results. More serious, involved fractures may take longer to heal with less “perfect” outcomes.
For example, the type of fracture you describe having (“tiny bits and pieces”) is referred to as comminuted. Surgery with hardware to hold the bones together is advised but it can take quite a while for the bones to knit back together. Other factors such as general health, bone health (any osteoporosis or brittle bones?), nutrition, hormone deficiency, and activity level can all impact healing and outcomes.
The more soft tissue damage around the joint, the more complicated treatment and recovery can be. It is not uncommon for the return of motion to take many months of hard work. But according to the studies done so far, most patients can expect a pain free elbow with full motion and normal function.
In some cases, there can be stiffness that limits full elbow extension. But unless you are an extreme athlete, there aren’t very many activities that really require zero degrees of elbow extension. Most patients tolerate up to a 30-degree elbow contracture. Contracture means the elbow doesn’t move past a certain point and it normally should. Contractures can be caused by a mechanical block in the joint itself or tightness in the soft tissues around the joint.
Since you are still in rehab, your surgeon and therapist are the best ones to advise you as to expectations and possible outcomes. They have some information that can help predict what might yet happen for you. Severity of fracture, type of surgery, and patient characteristics are all factors they take into consideration when advising someone like you.
Don’t hesitate to ask them this question but don’t be surprised if you get different answers or less of a prediction than you hoped for. There can be a wide range of results; each person is unique and different outcomes can be seen from patient to patient even with what looks like the same injury.