The Evaluation of Early Results after Total Hip Replacement in Dysplastic Hip Patients

Introduction. Dysplasia of hip joint leads to osteoarthritis. Suffer relatively young population in ages between 20 and 40. Due to severe changes of anatomy total hip replacement (THR) in dysplastic hip patients is a challenge for orthopaedic surgeons. Radical anatomical and biomechanical reconstruction may lead to high complication rate. The planning of the rotation center of hip joint is a key of success in the treatment of dysplastic osteoarthritis patients. Aim of the Study. The aim of the study was to evaluate the early results for dysplastic osteoarthritis patients (DOA), who underwent THR in Riga State Hospital of Traumatology and Orthopaedics in 2008-2009. Materials and methods. 63 THR were performed in 59 patients (50 women, 9 men). In all cases cementless acetabular components of endoprosthesis were used. Functional evaluation was made due to method of grading functional value of hip - Merle d'Aubigne and Postel. Hip dysplasia was divided in 4 groups due to classification after Crowe. Special digital orthopaedic programmes (AGFA, IMPAX) were used for preoperative planning and radiographic postoperative analysis. Results. Regarding to method of grading functional value of hip - Merle d'Aubigne and Postel we found out a significant improvement in range of movements, mobility and pain relief. Due to Crowe classification there were 19 patients with Crowe type I dysplasia, 29 with Crowe type II and 15 with Crowe type III. 43 acetabular cups were placed in the primary socket and 20 in the secondary socket. Radiographic analysis showed significant changes in location of rotation center of hip and offset after THR in dysplastic hip patients. Conclusions. Significant functional improvement was achieved after THR in DOA patients and the radiographic analysis showed significant decrease of horizontal location of RC and increase of offset after THR in DOA patients.