Total hip arthroplasty with insertion of the acetabular component without cement in hips with total congenital dislocation or marked congenital dysplasia

Background: End-stage osteoarthritis secondary to total congenital dislocat ion or severe congenital dysplasia of the hip (class B or C according to th e system of Eftekhar or type 2 or 3 according to the system of Hartofilakid is et al,) in adults presents special problems with regard to reconstructio n of the hip. The purpose of the present study was to assess the intermedia te-term results associated with the use of a porous ingrowth acetabular com ponent for the treatment of these difficult cases. Methods: We performed a prospective study of a consecutive series of twenty -one patients (twenty-four hips) who had had a primary total hip arthroplas ty with use of a hemispherical acetabular component that was inserted witho ut cement and fixed with screws. No patient was lost to follow-up. Three pa tients (four hips) died, of causes unrelated to the total hip arthroplasty, before a minimum duration of follow-up of five years. None of these patien ts had had revision. Of the remaining eighteen patients (twenty hips), fift een were women and three were men, Ten hips had total dislocation, and ten had severe dysplasia, Results: After an average duration of follow-up of eighty-three months (ran ge, sixty-four to 102 months), the average Harris hip score was 90 points ( range, 68 to 97 points), No patient had revision, loosening, or migration o f the acetabular component; pelvic osteolysis; or a continuous radiolucent line at the mesh-bone interface of the acetabular component. The average ra te of polyethylene wear was 0.08 millimeter per year (range, zero to 0.21 m illimeter per year). Conclusions: The porous ingrowth acetabular component that was used in the present study functioned well at the time of the intermediate-term follow-u p of this group of patients who had marked congenital dysplasia or total di slocation of the hip. The use of this component decreased the need for stru ctural acetabular grafts. This component appears to perform as well as larg er components of this design that have been assessed after similar duration s of follow-up.