All head position disorders can be called abnormal head posture, but abnormal head posture is not equal to compensatory head posture. Only abnormal head posture in connection with extraocular muscle disorders can be called compensatory head posture. Compensatory head posture is usually adopted to optimize visual acuity or to obtain single binocular vision. Abnormal head postures involve not only extraocular muscle disorders but also skeletal, muscular, neurologic, otolaryngologic and some eye disorders.