Nicholas M Brown1, Joe Morrison2, Scott M Sporer3, Wayne G Paprosky3. 1. Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, Illinois. 2. University of Illinois Chicago Medical School, Chicago, Illinois. 3. Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, Illinois; Department of Orthopaedic Surgery, Central Dupage Hospital, Winfield, Illinois.
Abstract
BACKGROUND: Revision total hip arthroplasty in patients with a nonsupportive superior acetabulum often requires secondary augmentation beyond a hemispherical cup to achieve reliable fixation. Treatment options include using a higher hip center, jumbo cup, custom triflange implant, cages, or filling the superior defect with a bilobed implant, structural allograft, or metal augments. We previously reported a cohort of 31 patients treated with porous-coated hemispherical cups and distal femoral allograft for Paprosky type IIIA acetabular defects. METHODS: The original cohort of 31 hips was retrospectively reviewed. Fourteen patients died with <15 years of follow-up, and 2 were lost to follow-up. This left 15 patients for evaluation including 5 males and 10 females, with an average age of 61 years (range: 37-74 years) at the time of surgery. Acetabular revision was performed with the use of a porous-coated hemispherical cup along with structural distal femoral allograft, cut to resemble the number 7, and secured with 6.5-mm cancellous screws with washers. RESULTS: Overall, 7 hips failed, resulting in a Kaplan-Meier survivorship of 72% at 25 years of follow-up. In surviving patients, radiographs demonstrated components to be well fixed, and average Merle d'Aubigné score increased from 5 to 10 points. There were a subset of patients that failed early (median: 6.2 years), but the remaining patients demonstrated excellent clinical and radiographic results. CONCLUSIONS: The use of distal femoral allograft can be considered in young patients with type IIIA acetabular defects that could benefit from restoration of bone stock.
BACKGROUND: Revision total hip arthroplasty in patients with a nonsupportive superior acetabulum often requires secondary augmentation beyond a hemispherical cup to achieve reliable fixation. Treatment options include using a higher hip center, jumbo cup, custom triflange implant, cages, or filling the superior defect with a bilobed implant, structural allograft, or metal augments. We previously reported a cohort of 31 patients treated with porous-coated hemispherical cups and distal femoral allograft for Paprosky type IIIA acetabular defects. METHODS: The original cohort of 31 hips was retrospectively reviewed. Fourteen patients died with <15 years of follow-up, and 2 were lost to follow-up. This left 15 patients for evaluation including 5 males and 10 females, with an average age of 61 years (range: 37-74 years) at the time of surgery. Acetabular revision was performed with the use of a porous-coated hemispherical cup along with structural distal femoral allograft, cut to resemble the number 7, and secured with 6.5-mm cancellous screws with washers. RESULTS: Overall, 7 hips failed, resulting in a Kaplan-Meier survivorship of 72% at 25 years of follow-up. In surviving patients, radiographs demonstrated components to be well fixed, and average Merle d'Aubigné score increased from 5 to 10 points. There were a subset of patients that failed early (median: 6.2 years), but the remaining patients demonstrated excellent clinical and radiographic results. CONCLUSIONS: The use of distal femoral allograft can be considered in young patients with type IIIA acetabular defects that could benefit from restoration of bone stock.