Wrestlers and boxers who sustain repeated blunt trauma to the ears can develop subperichondrial hematomas. These hematomas also may result from self-injurious episodes associated with certain behavioral disorders or neurodevelopmental disabilities, eg, autism spectrum disorder. When blood accumulates between the perichondrium and cartilage, part of or all of the pinna becomes a reddish-purple, shapeless mass. Infection, abscess formation, avascular necrosis, and destruction of the cartilage follow, leading to the development of cauliflower ear, a permanent deformity. Laceration, avulsion, and fracture of the pinna may each contribute to this process as well.