The use of an individual acetabular component for acetabular defect: a clinical case

BACKGROUND: The incidence of total hip replacements is increasing every year. Acetabular defects are becoming more frequent, with Paprosky type IIIA and above becoming more common. Recently, customized 3D-printed constructs have been used to remodel severe defects. We wanted to demonstrate the possibility of treating a patient with a severe acetabular defect by performing a one-stage revision endoprosthesis using a customized design.

CLINICAL CASES DESCRIPTION: A 69-year-old patient underwent primary total hip replacement of the right hip joint with a Biomet endoprosthesis for coxarthrosis in 2010. In 2011 — on the left side with a Zimmer endoprosthesis. In 2013 — revision endoprosthesis of the right hip joint due to instability was preformed. In the postoperative period, there were repeated dislocations with subsequent closed repositioning. In 2015, revision endoprosthetic replacement with a Burkh-Schneider antiprotrusion ring was done for recurrent dislocation. In november 2017, she was diagnosed with instability of the right total hip joint, for which she underwent revision hip replacement with a customized acetabular component.

HHS score before revision arthroplasty was 18 points, 1 month after surgery — 75 points, after 3 months — 65, after 6 months — 82, after 4 years — 74. Quality of life was assessed using the WOMAC scale: 92 points before surgery, 38 points 1 month after surgery, 31 points in 3 months, 15 points in 6 months, and 35 points in 4 years. As of the last visit, the patient moves with a cane, and still has a limp due to scar remodeling and gluteal muscles atrophy.

CONCLUSION: In case of severe acetabular defects, the use of individual components allows achieving reliable "implant–bone" fixation, which leads to improved functional results. However, in chronic pelvic bone integrity defects, the use of an individual acetabular component does not always achieve reliable stabilization. All existing methods for solving this problem are currently ambiguous and require further improvement.