Clinical outcomes of cement gun–assisted intramedullary nailing for femoral bone metastases: a retrospective case series

Abstract Background Surgical stabilization for femoral bone metastases is commonly performed to prevent or treat pathological fractures; however, local tumor progression may result in implant failure and reoperation. Cement gun–assisted intramedullary nailing (CG-IMN) allows extensive polymethylmethacrylate (PMMA) filling within the medullary canal, providing enhanced mechanical stability and facilitating early weight-bearing. This study aimed to evaluate the clinical outcomes of CG-IMN for femoral bone metastases. Methods We retrospectively reviewed 11 consecutive patients who underwent CG-IMN for femoral bone metastases at our institution between January 2008 and March 2025. Clinical data included patient demographics, primary tumor histology, presence of pathological fracture, revised Katagiri score, performance status (PS), lesion location, operative data, complications, reoperation rate, and ambulatory status at 1 month after surgery. Results The mean age was 72.5 years. Seven patients had impending fractures and four had pathological fractures. The mean revised Katagiri score was 5.3. PS improved significantly from 3.5 preoperatively to 1.4 postoperatively ( p < 0.01). Lesions involved the proximal femur ( n = 3), diaphysis ( n = 5), or both ( n = 3). Mean blood loss was 319 mL and operative time was 191 min. At 1 month, 9 of 11 patients (81.8%) were ambulatory. One patient (9.1%) required reoperation due to implant breakage after a fall. The 1-year implant survival rate was 90%. Conclusions CG-IMN provides stable fixation and functional improvement and may represent a useful surgical option, although further studies are required.