This is a deformity of the elbow region. Normally our arm turns outward from elbow. When there is a fracture of bone just above elbow (supracondylar fracture)and if proper treatment is not taken or if the fracture is bad with multiple pieces then the arm can get twisted inside and cause deformity called Gunstock (as its appearance resembles butt of the rifle) deformity or cubitus varus. This is mainly cosmetic deformity, as when the arm is straightened it appears very funny. 

This condition is completely correctible with surgery and can lead to normal cosmesis and function.