- Discussion:
    - Acetabular Component Menu: 
            - crowe classification:  (paprosky classification)
            - THR for DDH
            - bone grafting for THR: 
            - protrusio deformity in THR

    - cotyloplasty technique: by Hartofilakidis G, et al. (1996) 
            - technique creates a controlled comminuted fracture of the medial wall which allows for medialization of the cup; 
            - acetabulum is reamed w/ small reamers; 
            - rearmers are direted postero-superiorly to avoid the thin anterior column; 
            - reaming progresses until the outer surface of the inner wall is reached; 
            - using osteotomes, create a controlled fracture of the thin medial wall, but care is taken not to perforate the inner layer of periosteum; 
            - autogenous cancellous graft is then sandwhiched against the medial wall; 
            - the bone graft and medial acetabular wall are then pushed inward; 
            - the acetabular component is then cemented into place; 
            - ref: Treatment of high dislocation of the hip in adults with total hip arthroplasty. Operative technique and long-term clinical results.
                     Congenital hip disease in adults. Classification of acetabular deficiencies and operative treatment with acetabuloplasty combined with total hip arthroplasty.
    - medial protrusio technique: 
            - medial wall of a dysplastic acetabulum is intentionally perforated to allow coverage of the acetabular component without bone-graft support; 
            - results in placement of the medial aspect of the dome of the acetabular component medial to the Kohler line;
            - supplemental bone graft is an option;
            - multiholed revision cup for posterior superior and inferior screws for maximal support; 

- references: 
      - Acetabular Cup Revision With the Use of the Medial Protrusio Technique at an Average Follow-up of 6.6 Years.
      - Medial protrusio technique for placement of a porous-coated, hemispherical acetabular component without cement in a total hip arthroplasty in patients who have acetabular dysplasia. 
      - Total hip reconstruction in chronically dislocated hips. 
      - Total hip arthroplasty in chronically dislocated hips. Follow-up study on the protrusio socket technique. 
      - Acetabular medial wall displacement osteotomy in total hip arthroplasty: a technique to optimize the acetabular reconstruction in acetabular dysplasia.
      - Cotyloplasty in cementless total hip arthroplasty for an insufficient acetabulum.
      - Cementless total hip arthroplasty with medial wall osteotomy for the sequelae of septic arthritis of the hip.
      - Circumferential osteotomy of the medial acetabular wall in total hip replacement for the late sequelae of childhood septic arthritis of the hip.
      - [Total hip replacement for the treatment of Crowe IV congenital hip dislocation using small acetabular components combined with medial protrusio technique].
      - Evaluation of two surgical techniques for acetabular reconstruction in total hip replacement for congenital hip disease: results after a minimum ten-year follow-up.
      - Congenital hip disease in adults. Classification of acetabular deficiencies and operative treatment with acetabuloplasty combined with total hip arthroplasty.
      - Bone grafting in total hip arthroplasty for insufficient acetabulum
      - Low friction arthroplasty for old untreated congenital dislocation of the hip.