I have broken my elbow (undisplaced fracture) and the hospital did not plaster it but put it in a collar and cuff for 4 weeks. Why?
An undisplaced fracture means that a crack is present in a bone but there has been no loss of alignment or displacement of the bone. In other words everything is in the right place but the bone simply has a crack going through it. A collar and cuff provides rest and support to your arm and restricts your use of that arm. Not all fractures of the upper limb require plaster of paris. Fractures of the clavicle and undisplaced fractures of the neck of the humerus (upper arm bone extending from elbow to shoulder) are also treated by collar and cuff. There can be practical difficulties and risks associated with wrapping plaster around a flexed elbow. If on the other hand your fracture had been displaced it would have been necessary to have the bones put back in the correct anatomical position and possibly supported in place internally with wires or possibly screws. In that case some form of external support might also have been necessary. The collar and cuff currently allows you some limited use of your injured arm and means that you are less handicapped than you would have been had a rigid external support been applied.