Prosthetic reconstruction or hip transposition after periacetabular tumour resection?

Aims: Reconstruction after periacetabular tumour resection poses significant challenges in limb salvage surgery, particularly in the management of its complications and in optimizing functional outcome. This study aims to compare the outcomes of prosthetic reconstruction and hip transposition, and to develop a preoperative scoring system to assist surgical decision-making. Methods: Between January 2007 and December 2022, 197 patients underwent periacetabular tumour resection at two medical centres. Among them, 52 received prosthetic reconstruction and 62 underwent hip transposition, all with complete clinical and surgical data and postoperative follow-up. Inverse probability of treatment weighting and propensity score matching were applied to balance baseline preoperative variables. Surgical factors (e.g. operating time, blood loss, surgical margins) and postoperative outcome, including functional results and complications, were compared between groups. A preoperative scoring system was developed to predict the risk of major complications using Cox regression analysis and was validated through receiver operating characteristic analysis. Results: The Musculoskeletal Tumor Society (MSTS) scores showed no significant difference between the prosthetic reconstruction and hip transposition groups. However, the prosthetic group had a higher rate of complications requiring additional surgery, which was associated with decreased MSTS scores. Notably, patients in this group without complications had the highest functional outcomes. This trend remained consistent after adjusting for baseline characteristics. Hip transposition had a safer overall profile, while prosthetic reconstruction achieved better restoration of limb length and earlier mobilization. Based on these findings, we developed and internally validated a preoperative scoring system which included tumour region, gluteal invasion, and operation status to predict the risk of major complications (area under the curve = 0.77). Conclusion: Prosthetic reconstruction for periacetabular tumours is associated with a higher complication rate, potentially compromising functional outcome, while hip transposition is a safer and more conservative option. The proposed preoperative scoring system may help surgeons to choose the more appropriate reconstructive strategy based on the individual patient risk profile.