Hemipelvectomy and 3D Custom-Made Prosthesis Implantation: Early Surgical, Radiographic, and Functional Results-A...

Background: There are still insufficient studies based on large patient cohorts that evaluate both functional and surgical outcomes after internal hemipelvectomy and 3D-printed endoprosthesis implantation. This study aimed to determine how the method of pelvic bone defect reconstruction determines early functional, surgical, and radiographic outcomes. Methods: The aims of the study were achieved based on retrospective observations of 49 patients who underwent surgical treatment at several centres in Poland. All patients underwent internal hemipelvectomy and implantation of 3D-printed prostheses. Surgical parameters were assessed, including operative time, blood loss, and surgical complications (infections, implant loosening, dislocations), as well as bone osseointegration. Functional outcomes were assessed using the HHS and MSTS-93 scales, and pain intensity was measured using the VAS. Outcomes were stratified according to implant design and fixation method based on the West China Classification. Results: The most commonly performed procedures were internal hemipelvectomies of Enneking Type I + II and II + III, with reconstructions most frequently classified as WChC-Aa (15%) and WChC-Bb (44%). Functional assessments revealed significant improvement across all patients. Both the HHS and MSTS-93 values demonstrated marked progress from preoperative averages of 44 (HHS) and 12 (MSTS-93) to 64, 70.2, and 76 (HHS) and 19, 20, and 20.2 (MSTS-93) after 6 weeks, 3 months, and 6 months, respectively. Correspondingly, pain intensity decreased from a mean preoperative VAS score of 8.5 to 4.4, 3.4, and 3.2 after surgery. Osseointegration occurred in 53%, 75%, and 83% of patients after 6 weeks, 3 months, and 6 months, respectively. Wound-healing complications were observed in 6 patients, while deep infection developed in 4 cases. In 3 patients, the implant was removed. Implant loosening was noted in imaging studies in 7 patients (14%) and 8 patients (16%) at 3 and 6 months postoperatively, respectively. Local tumour recurrence was observed in 6 cases. Conclusions: The extent of pelvic tumour resection and the reconstruction method appear to influence surgical parameters, the risk of complications, and operative time. Functional outcomes measured using VAS, HHS, and MSTS-93 scales showed improvement following surgical treatment and tended to improve over time; however, these findings should be interpreted with caution given the relatively short follow-up period and the lack of assessment of minimal clinically important difference (MCID). The use of 3D-printed implants may facilitate precise pelvic reconstruction and enable early mobilization and rehabilitation.