Introduction: The lack of congruence between the acetabulum and femoral head in hip dysplasia compromise the passive stability of the hip joint resulting in increased stress on the acetabular labrum, joint capsule and the muscles acting close to the hip joint. Soft tissue injury is present in hip dysplasia, and pathology of the iliopsoas muscle has been found in 18-50%. To our knowledge, no studies have systematically examined the prevalence of soft tissue pathology in hip dysplasia.