What is the term for a neck deformity that bends the head to one side?

The term for a neck deformity that bends the head to one side is torticollis. Torticollis, often referred to as "wry neck," is characterized by the abnormal positioning of the head and neck due to muscle contractions or spasms. This condition can result from various factors, including muscular conditions, neurological disturbances, or even congenital issues. It leads to the head tilting to one side while the chin points toward the opposite shoulder.

The other conditions listed refer to different abnormalities. Scoliosis is a lateral curvature of the spine, kyphosis describes an exaggerated forward rounding of the back, and lordosis refers to an excessive inward curvature of the lower back. Each of these conditions affects different parts of the spine and posture rather than specifically relating to head positioning. Therefore, torticollis is the only term that accurately describes the specific neck deformity of tilting the head to one side.