Mid-term outcomes of cemented GMRS rotating-hinge knee prostheses for tumor reconstruction: A single-institution study from Japan.

Abstract

This study aimed to evaluate the short-to mid-term outcomes of the Global Modular Replacement System (GMRS) rotating-hinge knee prosthesis (Stryker) used in joint function reconstruction for bone and soft-tissue tumors and metastatic bone tumors. This study included patients who underwent lower limb joint function reconstruction using cemented GMRS rotating-hinge knee prosthesis at our hospital and were followed up for >2 years between July 2012 and December 2024. The implant and revision-free survival rates were evaluated, and complications requiring additional surgery were recorded. A total of 72 patients (31 males and 41 females) with an average age of 47 years (range, 13-84 years) were included in this study. The average follow-up period was 72.2 months (range, 26-148 months). The replacement sites were the distal femur in 50 cases, the proximal tibia in 21 cases, the total femur in 1 case. Of the 72 patients, 55 underwent initial surgery, and 17 underwent revision surgery. The 5-year implant survival rate was 86.7% (64/72), and the 5-year revision-free survival rate was 77.5% (58/72). The estimated 10-year implant survival rate remained 86.7%, indicating no additional implant failures after 5 years. Of the 72 patients, 14 (19%) underwent additional surgery due to infection (n = 7: 3 distal femoral replacement and 4 proximal tibial replacement), aseptic loosening (n = 4: 3 distal femoral replacement and 1 proximal tibial replacement), implant incompatibility (n = 1), and tumor recurrence/metastasis (n = 2). Cemented GMRS rotating-hinge knee prostheses demonstrated favorable short-to mid-term outcomes with stable implant survival beyond 5 years in this Japanese cohort. These findings supportthe mechanical durability of cemented GMRS reconstruction for limb salvage surgery around the knee.