Ice Cream Cone Pelvic Reconstruction after Peri-Acetabular Tumour Resection - Institutional Experience and Description of Implant Fatigue Failure

Aims: Reconstruction following resection of tumours involving the peri-acetabular area is challenging. Achieving acceptable long-term functional status remains difficult and complications are common. The aim of this study was to describe our experience of using the Stanmore ice-cream cone implant after major pelvic tumour resection and present 2 unique cases of implant fatigue failure. Methods: Ten patients with primary pelvic tumours involving the peri-acetabular region were treated with resection (type 2/2+3) and reconstruction using the Stanmore ice-cream coned pelvic implant between 2010 and 2019 at our centre. Retrospective analysis of our database and patient records was carried out to identify outcomes and complications. Results: Seven male and three female patients with a mean age of 46 years (range- 17-74 years) were treated with reconstruction using the Stanmore ice-cream cone implant. Chondrosarcoma (n=7) was the most common diagnosis. At a mean follow up of 67 months, 7 patients were alive without disease, 1 patient developed metastatic disease and 2 patients died of recurrent/metastatic disease. Dislocation occurred in 2 patients and 1 patient developed deep infection requiring re-operation for local control. Two patients developed fatigue failure of the implant, which has not been described in the literature. No revision was performed at the time of study. Conclusion: Reconstruction after peri-acetabular tumour resection remains challenging with high rates of complications. Surgical techniques and implant options are evolving but the ideal implant is yet to be established. Patients should be advised about potential complications including the need for further treatment related to implant failure.