Page 197 - Reconstructive Techniques in Musculoskeletal Tumor Surgery

Failure as a result of local recurrence (type 5 complication) occurred in 7%. Other long-term follow-up studies reported comparable rates (5%–6%)5, 6, 12, 33. Kinkel et al13 noted that the rate of extra-articular resection was substantially higher in their population (40%) compared with other series (0% – 13%; table 3). With the numbers we had, we found no di erence in relapse or complication risks between intra- and extra-articular resections. On the other hand, others reported that extra- articular resection is associated with an increased risk of infection and loosening7, 18. One may therefore question whether the high rate of extra-articular resection (46% of the primary reconstructions in our study) is truly justi ed. Careful evaluation of joint involvement with use of modern imaging techniques (PET-CT, gadolinium- enhanced MRI) may aid to avoid unnecessary extra-articular resections.
As a result of the fact that nearly all studies have used Kaplan-Meier survival analyses to compute implant survival rates, and because di erent classi cations and de nitions of failures have been used, it is di cult to adequately compare implant failure rates. Nevertheless, our long-term cumulative incidence rates of failure appear to be comparable to those reported by others8, 25, 32 and compare favorably with others5, 6, 11, 13 (table 3).
Despite needing more operative procedures for complications, we were able to achieve limb salvage in 90% of our patients. The majority of our patients had a MUTARS (but not necessarily the original MUTARS implant) in situ at latest follow- up, indicating that most complications could be adequately managed.
Although no system has yet proved ideal to restore normal function and demonstrate long-term retention of the implant, MUTARS modular endoprostheses
represent a reliable long-term option for knee replacement after tumor resection, 9 which seems to be comparable to other modular implants available to surgeons.
The cumulative incidence of implant failure was 20.7% at 10 years with mechanical
failure as the endpoint. Aseptic loosening was the most important mechanical complication. HA coating of uncemented implants may reduce the risk of
loosening, and we currently use uncemented HA-coated implants believing that
it is optimal for durable xation. We conclude that MUTARS represents a reliable
system with long-term results comparable to other prostheses and types of reconstructions for tumor resections about the knee.
Note: we thank Prof A.H.M. Taminiau, emeritus professor at the Department of Orthopaedic Surgery of the Leiden University Medical Center, for operating on a substantial number of the patients included in this study.
MUTARS knee replacement
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