Grenzen der zementfreien Revisionsarthroplastik

Revision of an acetabular component in a patient who has severe periacetabular bone loss is a complex problem, particularly when there is not enough bone stock to allow placement of an acetabular component near the normal anatomical hip center. To fill the defect, a valuable option for revision arthroplasty is the cementless oblong revision cup (LOR). Methods: 50 consecutive revisions of the acetabular component were performed in 48 patients. The mean age at the time of revision was sixty-one years (range, thirty-three to seventy-eight years). Forty-eight hips were available for follow-up, at a mean of thirty-two months (range, eighteen to sixty-one months). The acetabular defect classified according to Paprosky, the migration and the radiolucencies were followed radiologically. Results: 8 hips (16%) were revised again: two because of infection (4%) and six because of instability (12%). The revised hips are not associated to the preoperative degree of acetabular defect (34% defect type III) (P > 0.05). The mean Harris Hip score was corrected from 36.5 (range, 7.5 to 92.5) to 78.2 points (range, 47.6 to 97.6) (P 0.05). However, patients with multiple revisions had a significantly reduced clinical outcome than patients with the first revision (P 0.05). Conclusion: The authors support the use of the cementless oblong revison cup if contact can be made with host bone to more than 50%. If this is not possible, acetabular bone reconstruction combined with a roof ring and a cemented cup is the component of choice.