Page 65 - Reconstructive Techniques in Musculoskeletal Tumor Surgery

presence of malignant disease, the anatomical region involved and, in some cases, age and pre-existing implants31. It seems that most risk factors are unalterable and it is therefore conceivable that the rate of infection will remain high.
Modi cations of the device, and changes in reconstructive technique, may
help reduce the rate of infection. Favorable reports on the silver coating of endoprostheses have been presented by Gosheger et al32, who described a lower
rate of infection for silver-coated prostheses in a rabbit study. In another study, 3 they reported that no toxicological side-e ects occurred in 20 patients, but long-
term results are still lacking33. Fisher et al4 reported on 27 patients with cemented
‘ice-cream cone’endoprosthetic reconstructions after resection of a periacetabular
tumor. Although follow-up was limited, only three infections were seen, and all were successfully treated by surgical debridement and the administration of systemic
antibiotics. The authors stated that one of the key features was the large volume
of antibiotic-laden (gentamicin, vancomycin) bone cement applied around the
prosthesis. This was believed to result in a high concentration of antibiotics around
the prosthesis, thus not only minimising the risk of infection, but also allowing
e ective control if it occurs.
The functional outcome scores for reconstruction of a periacetabular defect show considerable variation. Our functional outcome scores are comparable with some previous reports8,19,34, but compare unfavorably with those of more recently published studies3,4. However, in the latter studies, follow-up was rather short. Only one of our patients used analgesics on a daily basis. Most authors have not reported analgesic usage, but Aljassir et al8 noted that 27 of their patients with a saddle prosthesis (Waldemar-Link, Hamburg, Germany) used narcotics on a daily basis.
Despite the rather poor functional results, the SF-36 physical component scores were higher than those of age- and gender-matched controls. This might be explained by the fact that it re ects patients’ perception of function, rather than their real function. It suggests that patients with an orthopaedic pelvic malignancy cope relatively well with impaired function after this type of extensive surgery. The mental component scores seem to con rm this.
Our study has a number of limitations including the limited number of patients. There was a wide range in follow-up, mainly due to rapid progression of disease which could mean that presented rates of complication underestimate the genuine long-term rates. This is however inherent to retrospective studies on patients with aggressive malignancies.
Pedestal cup endoprosthesis
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