To evaluate the clinical efficacy and safety of modular hemipelvic prostheses in elderly patients with periacetabular metastatic tumors.

A retrospective analysis was conducted on 25 patients who underwent reconstruction with a modular hemipelvic prosthesis for bone defects following resection of acetabular metastatic tumors. These patients were treated at Peking University People's Hospital and The First Affiliated Hospital of Ningbo University between March 2018 and March 2024. Data recorded included operative time, intraoperative blood loss, and postoperative complications (infection, tumor progression, prosthesis dislocation, prosthesis fracture) during follow-up. Patient symptoms and functional improvement were assessed using the Musculoskeletal Tumor Society (MSTS) scoring system before and after surgery.

A total of 25 patients were included (8 males, 17 females), with a mean age of 67.64±4.84 years. All surgeries were successfully completed. The mean operative time and intraoperative blood loss were 251.80±44.79 minutes and 1 972.00±709.18 mL, respectively. Perioperative complications included deep vein thrombosis in 2 patient, surgical site infection in 2 patients, and prosthesis dislocation in 1 patient. The mean follow-up duration was 25.40±11.33 months (range: 6-46 months). During follow-up, local tumor recurrence occurred in 3 patients. Four patients died due to progression of their primary disease at postoperative months 6, 8, 14, and 19, respectively. The mean MSTS score at the final follow-up 20.0 (18.5, 25.0) was significantly higher than the preoperative score 7.0 (4.5, 11.0) (P<0.001).

Short-term follow-up confirms that the use of modular hemipelvic prostheses for reconstructing bone defects after resection of periacetabular metastatic tumors in elderly patients demonstrates a high safety profile and enables patients to achieve favorable functional outcomes.