LTHOUGH atlantoaxial rotatory subluxation is a well-known entity that affects the pediatric popu- lation, 4 combined atlantoaxial and occipitoatlantal subluxation is a rare disease. We describe a new case in a teenage girl. Case Report History. This 17-year-old girl was admitted to our de- partment with a history of torticollis. She presented with severe neck pain, having experienced typical spontaneous torticollis a few days before admission and received anal- gesic drug therapy for 3 days. After that, she underwent a unspecified chiropractic manipulation that she refused to describe. Examination. At clinical examination, her head was slightly rotated to the left and tilted on the right (Fig. 1), but there was no real torticollis. Results of the neurological ex- amination were otherwise normal. Plain x-ray films (Fig. 2) revealed an abnormal location of the lateral mass of C-1 and the transverse process. A three-dimensional (3-D) computerized tomography (CT) study (Fig. 3) revealed double axial subluxation, with C-1 turned to the left and C-2 to the right, which perfectly ex- plained the clinical presentation. Magnetic resonance im- aging demonstrated compromise of the spinal canal and normal transverse ligament. The results of vertebral angiog- raphy were normal. Operation. An initial attempt to reduce the double sub- luxation was made after induction of a general anesthetic to produce pharmacological paralysis. However, fluoroscopi- cally guided cranial traction did not produce any mobiliza- tion of C-1 or C-2. Thus, we concluded that extensive le- sions of the ligament must have occurred that caused double instability of occiput (Oc)–C1 and C1–2. An open operative J Neurosurg (Spine 2) 90:258–260, 1999 258 Imaging features in combined atlantoaxial and occipitoatlantal rotatory subluxation: a rare entity Case report PABLO BOUILLOT, M.D., STÉPHANE FUENTES, M.D., HENRY DUFOUR, M.D., LUIS MANERA, AND FRANÇOIS GRISOLI, M.D. Departments of Neurosurgery and Neuroradiology, Centre Hospitalier Régional et Universitaire de Marseille La Timone, Marseille, France  The authors report a new case of combined atlantoaxial and occipitoatlantal rotatory subluxation in a 17-year-old girl. They describe the clinical and imaging features of this rare entity. An occiput–C2 arthrodesis was performed. KEY WORDS • atlantoaxial rotatory subluxation • occipitoatlantal subluxation • three-dimensional computerized tomography A J. Neurosurg: Spine / Volume 90 / April, 1999 FIG. 1. Photograph showing the appearance of combined at- lantoaxial and occipitoatlantal subluxation in our patient at presen- tation. The head is slightly rotated on the left side and tilted on the right.