We report the clinical and radiographic results of the Chiari pelvic osteotomy in 22 hips (22 patients) over eight years after surgery. The average follow up period was 11 years and one month. Subjects were divided into two groups, group A which did not show any advance in the patients osteoarthritis (OA) and group B which did. We utilized the Japanese Orthopaedic Association (JOA) score for clinical evaluation and CE angle, Sharp angle, AHI, lateral shift, medial shift and osteotomy level. Clinically excellent or good results according to the JOA score were obtained in 20 hips (90.9%). CE angle, AHI and lateral shift decreased significantly (p<0.05) in group B during follow up. A good correlation between the lower osteotomy level (below five millimeters) and lateral shift were noted. Important factors to prevent lateral shift were as follows; 1), To have adequate coverage by medialization of the femoral head, 2) The osteotomy should not be performed at less than five millimeters. These factors seem to be important for achieving good results.
