Rider's bone ossify in the: (A) Adductor Longus, (B) Gluteus Maximus, (C) Lateral head of Gastronemius, (D) Tibialis Posterior
Answer is A. In horse riders, the rounded tendon of adductor longus frequently gets calcified as a result of its friction together with the horseback. This calcified tendon is named rider's bone.Reference: Chaurasia Volume II; 7th edition; Page no: 41