Surgical Considerations: Megaprosthesis
From 1990 to 1997, Muller et al. treated 9 patients with hemipelvectomy and insertion of a megaprosthesis (Howmedica, Kiel, Germany) that had computer-aided design. He reported very high complication rates(8/9 patients), mainly deep infections, dislocations, hematomas. Seven of those patients required surgical intervention. Functionality was not discussed.9
Custom Made Hemipelvis
Windhager et al. treated periacetabular sarcomas with a custom prosthesis (Howmedica, Germany). The size of the prosthesis was generated from 3-D CT reconstructions with resection margins defined by the surgeon. He reported satisfactory results with less complications than with arthrodesis, pseudoarthrosis, or saddle prosthesis.
Major surgical drawback: prosthesis needs to be exact fit as it is pre-ordered and made of precise measurements from 3-D Computed Tomography models.
Other options include:
Massive allografts/autografts and composite allografts.
Some proponents have had success with these techniques, but major complications are somewhere in the 25-35% range.
The most common complication being infection, loosening, dislocation and in autografts, patients sustain fractures.11
Which led to the development of the saddle prosthesis.