Complex Hip Revision

This is a 25 year old with Down’s syndrome and a history of right hip dysplasia who underwent a Peri Acetabular Osteotomy at age 6. She did well until age 17 when she suffered a stress fracture of her femoral neck, potentially from impingement of the femoral neck on the realigned acetabulum. She underwent a hip replacement, which unfortunately loosened a few years after replacement. A revision was done, which was undoubtedly complicated by her habitus (Figure 1 and 2).

The revision also loosened in a short time frame. I took over management and an infection workup demonstrated a sensitive Staph Aureus. I removed the acetabular components, but the stem was a long well-fixed monoblock stem (not a stem I typically use) that was essentially impossible to remove without destroying most of the femur, so I made a judgement call to retain it. I placed a high dose antibiotic spacer and treated with IV antibiotics (Figure 4), with a plan for chronic suppression for the femoral component.

By this point, the acetabulum was essentially flat, with no walls and very little bone to support an off-the-shelf reconstruction (Figure 3 and 5). I designed a custom acetabular component for the reconstruction.

She recently underwent the reconstruction procedure and did well (Figure 6).

Given the low likelihood of her ability to comply with restricted weight bearing, we designed the implant with robust posterior column fixation (“ice cream cone” style stem and a long Ostecentric fastener) keeping in mind that she would be WBAT immediately after surgery. The comparison of the preop plan and the post-op x-rays demonstrates that the procedure went according to plan (Figure 7). She is now walking, WBAT as expected. Her hip feels great to her.