It almost sounds like a complete fracture. If it is not bleeding and is able to use the wing somewhat, then this seems like he/she is able to cope with the injury. Birds have hollow bones, so depending on the injury, sometimes the bone can heal without further trauma. This bird may have gotten lucky. However, it still needs to be seen by a veterinarian to ensure there is no underlying infection and the possible remaining bone/wing can be amputated so that no further injury occurs by the bird being caught on something such as limb or other object. Furthermore, since it cannot fly, it will not be able to protect itself from predators or other injuries. The Regal Swan