THE TIME COURSE OF THE PELVIC INCLINATION ANGLE AFTER TOTAL HIP ARTHROPLASTY FOR 5 YEARS.

Materials and MethodsWe treated 60 hips in 60 patients (8 males and 52 females) with cementless THA that were performed from January 2007 to December 2009 in our hospital. 48 osteoarthritis hips, 5 rheumatoid arthritis hips and 7 idiopathic osteonecrosis hips were included. All patients were performed THA with VectorVision Hip navigation system (BrainLAB, Feldkirchen, Germany). We used AMS HA cups and PerFix stems (KYOCERA Medical co., Osaka, Japan). The mean age of surgery was 61 years old (35–79 years old). The pelvic inclination angles (PIA) were measured with anteroposterior radiographic image in accordance with the Doiguchi's method.ResultsThe amount of change of the pelvic inclination angle between supine and standing position was 0.6 degrees prior to surgery, 0.7 degree at 1 year after surgery and 2.4 degrees at 5 years after surgery. 7 patients prior to surgery, 7 patient at 1 year after surgery and 18 patient at 5 year after surgery changed more than 5 degrees between supine and standing position...