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.

Next page