Page 205 - Reconstructive Techniques in Musculoskeletal Tumor Surgery

no mechanical failures of the implant itself. Infection occurred in nine patients (47%), six of whom required removal of the prosthesis. The implant survival rate at ve years was 50% for all reasons, and 61% for non-oncological reasons. The mean MSTS score at nal follow-up was 49% (13 to 87). We concluded that we no longer used this implant and advised caution if using it for reconstruction after periacetabular tumor resection.
Despite the poor results obtained with periacetabular reconstruction using the pedestal cup endoprosthesis, we considered the basic idea behind the implant suitable for pelvic reconstruction. Our experiences were incorporated in the design of the LUMiC. Chapter 4 re ects on a retrospective European multicenter evaluation of clinical outcome in 47 patients who underwent reconstruction with the LUMiC after resection of a periacetabular tumor. The aim was to evaluate the short- to mid-term results of this novel implant. We demonstrated that the risk of dislocation was signi cantly lower in reconstructions with a dual-mobility cup than in those without (HR 0.11, i.e. an 89% reduction in dislocation risk in favor of the dual mobility cup). Loosening occurred in two uncemented reconstructions with poor initial xation; both were revised. Infections occurred in 28%. We showed that the duration of surgery and amount of blood loss were associated with the risk of infection. The cumulative incidences of implant failure at 2 and 5 years were 2.1% and 17.3% for mechanical reasons and 6.4% and 9.2% for infection, respectively. Mean MSTS functional outcome score at follow-up was 70% (30 to 93). We concluded that, at short-term follow-up, the LUMiC prosthesis demonstrated a low frequency of mechanical complications and failure when used to reconstruct the acetabulum in patients who underwent major pelvic tumor resections. Moreover, we stated that dual-mobility articulation should be used after any internal hemipelvectomy to reduce the risk of dislocation.
Part II – Management of Extremity Bone Tumors
Intercalary allografts have long been the most important reconstructive option for the reconstruction of large segmental (diaphyseal) defects. Chapter 5 described a retrospective evaluation of all intercalary allograft reconstructions in the treatment of primary bone tumors in all four centers of orthopaedic oncology in the Netherlands between 1989 and 2009. The incidence of and risk factors for failure and complications, time to full weight bearing, and optimal xation methods were evaluated in a total of 87 reconstructions. Complications occurred
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General summary
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