In children with supracondylar humerus fractures, there are a number of complications that may occur if appropriate treatment is not provided in a timely manner, including inversion of the elbow and fishtail deformity.
An angular deformity of the elbow (elbow inversion, also known as a gunstock” deformity) is a long-term complication of a supracondylar fracture. Elbow pronation mainly affects the appearance of the elbow and does not usually affect function. However, in a small number of cases it can lead to ulnar nerve palsy, which can occur many years after the fracture has occurred. Fishtail deformity is the appearance of the distal humerus after the fracture has healed but ischaemic necrosis of the lateral talus has occurred.