Tumor endoprostheses of the knee joint after
limb salvage surgery is associated with high rates of complications, which has introduced great challenges to a delayed
revision surgery. The aim of the study was to summarize the failures, functional outcomes and prosthetic survival in revision
tumor endoprostheses of the knee joint.
METHODS: The clinical data of 20 patients with malignant
tumors who received prosthetic revisions after
limb salvage surgery from January, 2000 until January, 2018 were retrospectively reviewed. The cohort was constituted of 11 male and 9 female patients with a mean age of 34.1 years (range, 16 to 66 years).
Infection cases received two-stage revisions after removing
prostheses initially, while all other cases received one-stage revisions. Revision reasons and complications were well documented and analyzed.
RESULTS: All patients received complete follow-up with a mean time of 64.7 months (range, 27 to 155 months). A total of 6 (6/20, 30.0%) patients experienced a second complication after
revision surgery, of whom, one patient with deep
infection experienced repeated
infections after prosthetic revision and received
amputation surgery; one patient revised of prosthetic fracture experienced an
infection and received a second-stage
infection revision; one case revised of prosthetic loosening had deep
infection receiving anti-infective
therapy with
prostheses still in position; one case having
wound complication healed after receiving two times of
debridement surgery; one MBGCT patient experienced a second aseptic loosening 6 years after the initial loosening thus undergoing a second revision; a recurrent
osteosarcoma patient died of pulmonary
metastasis 3 years after
revision surgery. Kaplan-Meier survival curve indicated a 5-year survival rate of initial
prostheses was 75%. The Musculoskeletal
Tumor Society (MSTS-93) score [20.9 (range, 15 to 27 scores)] at 1 year after
revision surgeries was significantly improved (p < 0.001) when compared with the score [17.2 (range, 13 to 21 scores)] before revisions.
CONCLUSION: Prosthetic mechanical problems, aseptic loosening and
infections were primary reasons for revisions after
tumor endoprostheses of the knee joint. Although
revision surgeries were complicated while still associated with high risk of failure, which remains the remedy strategy for
limb salvage and functional recovery in those patients.