Combined Periacetabular and Proximal Femoral Osteotomies for Healed Perthes

Abstract

Following the occurrence and healing of Legg-Calve-Perthes (LCP) in childhood, residual hip joint deformity of variable severity can occur, which is characterized by morphological features of both femoral acetabular impingement (FAI) and variable secondary relative acetabular deficiency. The femoral head is enlarged and aspherical and characteristically pathologically impinges against the acetabulum in hip flexion, in internal rotation in flexion and abduction. It also typically impinges in adduction. The femoral neck is relatively short, the greater trochanter high riding resulting in a functional coxa vara. The high-riding trochanter also potentiates both abductor insufficiency and extra-articular impingement. Secondarily, the acetabulum variably remodels in response to its long-standing articulation with a post-Perthes enlarged aspherical femoral head. If the acetabulum is dysplastic, both femoral head instability and labral-chondral rim overload can occur.

Residual post-Perthes hip joint deformity can become symptomatically problematic in mid-adolescence with both restricted painful hip motion and discomfort while walking or running. Recently it has been shown that comprehensive correction of the complex problematic post-Perthes deformity (FAI impingement and acetabular dysplasia) can be achieved in order to preserve the hip joint. Following comprehensive correction, patients have experienced both resolution of hip joint pain and increased hip joint flexibility with a marked improvement in hip joint function.