Cup-cage construct for massive acetabular defect in revision hip arthroplasty- A case series with medium to long-term follow-up.

OBJECTIVE

Cup-cage reconstruction has emerged as a possible solution for managing massive acetabular defects with a few existing studies reporting encouraging results at mid-term follow-up. We present our experience with this unitised construct.

METHOD

Six patients (7 hips) with a mean age of 76 years (73-81) were revised due to catastrophic aseptic failure of a primary cup implanted 10-19 years previously, having a Paprosky type 3B acetabular defect.

RESULTS

At a mean follow-up of 72 months (63-140) no cases have required re-revision. Oxford Hip Scores improved from an average of 8 (1-17) preoperatively to an average of 36 (18-45) at the last follow-up. WOMAC scores preoperatively averaged 76 (49-96) and postoperatively averaged 26.5 points (0-69) at the last follow-up. SF-12 scores improved in both components. One patient showed non-progressive osteolysis around the ischial flange and one had less than 5 mm migration of the construct. One patient died of unrelated causes.

CONCLUSION

Our study presents one of the longest follow-up of cup-cage construct and supports the previously reported good results; it encourages the use of this construct in reconstruction of massive acetabular defect, with or without pelvic discontinuity.