Abstract
Dysplasia of the hip joint (DDH) is a severe pathology of the musculoskeletal system which, if not diagnosed and treated in time, leads to impaired function of the hip joint. This leads to osteoarthritis, which requires surgical intervention. This case report describes a case where a cementless total hip arthroplasty (THA) of the left hip joint with a 6.5 cm transverse subtrochanteric shortening osteotomy (SSO) was performed. A special feature was the use of a newly developed plate that provides rotational and axial stability at the osteotomy site. With further observation and management of the patient. It is worth noting that this study and follow-up of the patient is ongoing. Keywords: developmental dysplasia of the hip (DDH), arthroplasty, subtrochonteric osteotomy.