coxathrosis secondary to the untreated developmental dysplasia of the hip is still encountered against all the screening and early treatment methods.T.H.A in DDH presents challenging surgical problems to the orthopedic surgeons due to the associated anatomical changes and the technical difficulties related to the bone deficiency in the acetabulum. The purpose of the study is to examine the clinical and technical problems associated with reconstruction of the hip in patients with congenital dysplasia and to offer recommendations for their Solutions.