Abstract
BACKGROUND: The precise acetabular reconstruction has historically been a challenging procedure. 3D-printed patient-specific guide (PSG) and computer navigation (CN) technologies have been used to assist acetabular component positioning and pelvic reconstruction. This precise reconstruction approach may translate into clinical benefit. METHODS: The clinical data of 84 patients who underwent periacetabular malignant tumor resection and screw-rod-acetabular cage system reconstruction in our center from January 2013 to December 2020 were retrospectively analyzed. Patients were divided into four groups: free hand (FH) group, PSG group, CN group, and PSG combined with computer navigation (PSG + CN) group. The operation time, intraoperative blood loss, and number of fluoroscopy views were recorded. The oncological prognosis, radiographic measurements of the acetabulum, limb function data, and postoperative complications were compared among groups. And finally, we evaluated the risk factors for mechanical failure of the prosthesis. RESULTS: The postoperative X-ray and computed tomography (CT) scan revealed that the vertical offset discrepancy (VOD) between affected side and contralateral side was 8.4±1.9, 5.9±2.2, 4.1±1.3, and 2.4±1.2 mm in each groups; the horizontal offset discrepancy (HOD) was 9.0±1.9, 6.1±2.2, 3.2±1.3, and 2.1±1.2 mm, correspondingly; the abduction angle discrepancy (ABAD) was 8.6°±1.8°, 5.6°±2.0°, 2.5°±1.3°, and 1.8°±0.9°, respectively; the anteversion angle discrepancy (ANAD) was 5.9°±1.6°, 3.6°±1.7°, 2.9°±1.6°, and 1.9°±0.9°, correspondingly. Statistical results show that the PSG + CN group was superior to the FH group and the PSG group in terms of acetabular position and limb function (P<0.05). Body mass index (P=0.040) and resection type (P=0.042) were found to be the high-risk factors for mechanical failure of the prosthesis. CONCLUSIONS: PSG + CN has potential advantages in improving the accuracy and safety of acetabular positioning and reconstruction.