It is important to understand the difference between a Mallet finger injury and a Swan Neck Deformity. Occasionally, a mallet finger injury can turn into a Swan Neck deformity if left untreated. A Swan Neck deformity can be misdiagnosed as a Mallet finger. It is important to have a Hand Doctor determine which injury you have, as the splinting and recovery are VERY different. This video explains what is a Swan neck deformity.