A 65-year-old male with a history of both THAs and two left hip revision surgeries due to an infection presented for left hip THA conversion. In brief, he had previously undergone both THAs at another hospital 7 and 8 years ago (Fig. 1A). However, an infection developed in the left THA site and the implant was removed. After curettage, an antibiotic loaded acrylic cement (PROSTALAC) prosthesis was inserted at our hospital (Fig. 1B). However, the infection, which was due to methicillin resistant staphylococcus (MRSA), had not been eradicated 4 months later. Accordingly, we performed revision surgery involving PROSTALAC removal, curettage, debridement, and trochanteroplasty (Fig. 1C). Proximal half of greater trochanter was exposured after stripping of gluteus medius and was inserted into the acetabulum. Postoperatively, a double splint (anterior and posterior) was applied in abduction position and then have kept for 2 weeks.

Four years after trochanteroplasty, a physical examination revealed leg length shortening of 1.5 cm, and range of motion limitation; flexion 60°, internal rotation 0°, external rotation 30°, abduction 45°, and adduction 10°. A laboratory examination performed at the time revealed a WBC count of 7000/mm³, ESR at 25 mm/hr, and CRP at <0.5 mg/dl. These lab findings were sustained for about one year before revisional THA without any other signs or symptoms of infection. Radiographs of the hip (AP and lateral views) obtained at this time showed that bone quality of the proximal femur and of the acetabular side were much improved (Fig. 1D) to the extent that revision THA was possible. The patient favored revisional THA surgery to improve function, and thus, surgery was scheduled.

To approach the surgical field, we performed greater trochanter osteotomy and confirmed the absence of infection by frozen biopsy. To reconstruct the acetabulum, we used an acetabular roof reinforcement ring with a hook (ARRRH; Zimmer, Baar, Switzerland) and a cementless conical stem to reconstruct the femoral side (Cone prosthesis; Zimmer, Winterthur, Switzerland). A cavitary bone defect was present in the acetabular side, and thus, we used a morcellized allograft and an ARRRH. In the femoral side, we decided that bone stock was sufficient to allow stable fixation with a cementless stem. Subsequently, we reattached the great trochanter distally to improve abduction lever arm. The patient was followed up for 3 years (Fig. 1E). His blood laboratory findings at last follow up were WBC of 7600/mm³, ESR at 12 mm/hr and CRP at <0.5 mg/dl. There were no signs or symptoms of infection and the patient was able to walk without additional support.

The aims of revisional THA are to extract the failed prosthesis, implant new components to provide longterm stable fixation, and manage bone loss by augmenting deficient bone. If an infection is present, a two-stage procedure is usually performed to eradicate infection and then to implant the new components and reconstruct deficient bone3).

To treat the infected THA in our patient, we also chose two stage reconstruction4), but after the first stage surgery, the infection was sustained and MRSA was found to be the causative organism, and thus, the PROSTALAC was removed. At this stage, there was insufficient bone stock for revisional THA, because of a prolonged femoral stem infection. In this situation, the Girdlestone operation provides an another treatment option, but it may result in nearly useless pseudarthrosis or ankylosis and marked shortening of the affected extremity. Accordingly, we considered trochanteroplasty a good option in our patient, because it can provide a more stable joint and less leg shortening than the Girdlestone operation.

Trochanteroplasty was first described by Colonna5) and was popularized by others1,6,7). Although it was first performed in adult patients, it was gradually regarded as a typical salvage procedure in infants with complete destruction of the femoral head and neck. The rationale for adopting trochanteroplasty in children is as follows; (1) the greater trochanter is viable, and therefore, has growth potential, and (2) when hyaline cartilage covering the trochanter is placed inside the acetabulum, the trochanter tends to form a globular femoral head-like shape8). However, no report has been issued on trochanteroplasty in adults, which is somewhat surprising because we believe that it can also increase proximal femur bone quality in adults. In the described case, we performed trochanteroplasty as described by Colonna5), and at last follow-up, 4 years after the procedure, bone quality had substantially improved.

Gerber A et al.9) found that in patients treated by acetabular revision using an ARRRH, the periacetabular bone stock was reconstituted and good clinical and radiographic results were obtained in cases with adequate ring fixation during surgery. Because acetabular bone quality is improved after trochanteroplasty, sufficient stability can be obtained using an ARRRH and allograft. If the bone stock on the acetabular side is too poor to achieve sufficient stability using an ARRRH, then the more difficult acetabular reconstruction option using an impacted bone graft and metal mesh and a morcellized allograft can be adopted. In the femoral side, we used a cementless cone-shaped stem because of deformation of the proximal femur and calcar portion. In a very poor proximal femoral bone stock, an impaction bone graft in the femoral side can also be considered, but the procedure is more difficult and poses a greater risk of infection.

Revisional THA for a septic hip is usually difficult because of secondary loss of bone stock. Trochanteroplasty performed in the described patient successfully improved bone quality of the femur and the acetabulum. We considered that trochanteroplasty could be considered as a salvage procedure in patients with an uncontrolled THA infection and as an interim procedure prior to revisional THA.