Abstract
Reconstructing severe acetabular defects in revision total hip arthroplasty remains a challenge. When bulk allografts are used alone to support components, high failure rates are reported within five years. But satisfying results are obtained in most cases when a reinforcement cage and cement are used in combination with bulk allograft.
This video demonstrates a technique used at Anderson Orthopaedic Institute that employs an anti-protrusio acetabular support ring with particulate allograft. Considered a salvage procedure, the approach provides an option when a hemispheric acetabular component cannot be adequately placed or properly positioned on host bone. It is recommended for low-demand, elderly patients or those with multiple failures in which no other reconstruction alternative is viable.
The partial-pelvic reconstruction ring used in this case has a caudal flange. It comes in multiple sizes and also has flexible flanges that can be contoured to the ilium. The caudal flange secures fixation to the ischium. The acetabular cage enables re-creation of a normal hip center and, thus, improved hip joint stability. Disadvantages are the extensive exposure required and lack of opportunity to trial reduce components.
As shown in the video, unique aspects of the surgical exposure are: sciatic nerve exposure to prevent injury during surgery; a trochanteric osteotomy to mobilise abductors and allow exposure and fixation of the cage to the ilium; extensive mobilisation of the femur to visualise acetabular defects; and exposure of the ischium for inferior fixation of the cage.
The abstracts were prepared by Mrs Dorothy L. Granchi, Course Coordinator. Correspondence should be addressed to her at PMB 295, 8000 Plaza Boulevard, Mentor, Ohio 44060, USA.
