Reconstruction with 3D-printed prostheses after type I + II + III internal hemipelvectomy: Finite element analysis and preliminary outcomes

Abstract

Background: Prosthetic reconstruction after type I + II+ III internal hemipelvectomy remains challenging due to the lack of osseointegration and presence of giant shear force at the sacroiliac joint. The purpose of this study was to evaluate the biomechanical properties of the novel 3D-printed, custom-made prosthesis with pedicle screw–rod system and sacral tray using finite element analysis.Methods: Four models that included one intact pelvis were established for validation. Forces of 500 N and 2,000 N were applied, respectively, to simulate static bipedal standing and the most loaded condition during a gait cycle. Biomechanical analysis was performed, and the results were compared; the preliminary outcomes of four patients were recorded.Results: For the reconstructed hemipelvis, stress was mainly concentrated on the sacral screws, bone–prosthesis interface, and upper endplate of the L5 vertebra. The optimization of the design with the sacral tray structure could decrease the peak stress of the sacral screws by 18.6%, while the maximal stress of the prosthesis increased by 60.7%. The addition of the lumbosacral pedicle–rod system further alleviated stress of the sacral screws and prosthesis by 30.2% and 19.4%, respectively. The site of peak stress was contemporaneously transferred to the connecting rods within an elastic range. In the retrospective clinical study, four patients who had undergone prosthetic reconstruction were included. During a follow-up of 16.6 ± 7.5 months, the walking ability was found preserved in all patients who are still alive and no prosthesis-related complications had occurred except for one hip dislocation. The Musculoskeletal Tumor Society (MSTS) score was found to be 19.5 ± 2.9.Conclusion: The novel reconstructive system yielded favorable biomechanical characteristics and demonstrated promising preliminary outcomes. The method can be used as a reference for reconstruction after type I + II + III hemipelvectomy.

Biomimetic design and clinical application of Ti-6Al-4V lattice hemipelvis prosthesis for pelvic reconstruction

“…Many studies focused on surgical technique and prosthesis design in periacetabular defect reconstruction and reported reasonable clinical and function outcomes [ 28 – 32 ]. However, for tumor resection without ilium preservation, fixing the prosthesis to the sacrum is surgical difficult because the flat surface of the sacroiliac joint is vulnerable to shear loading [ 11 ]. Despite the utilization of multiple screw fixation could achieve primary stability, long-term non-integration between the implant and host bone may result in a high incidence of reconstruction failure [ 17 ].…”

“…Until now, several prostheses have been developed for pelvic reconstruction, such as saddle prosthesis [ 5 , 6 ], ice cream cone prosthesis [ 7 , 8 ], and modular hemipelvis prosthesis [ 1 , 9 , 10 ]. However, when the ilium and acetabulum are completely removed, the saddle prosthesis and ice cream cone prosthesis cannot be fitted and fixed, which requires sufficient bone stock of the residual ilium for implant anchorage [ 11 , 12 ]. In this situation, modular hemipelvis prosthesis has gained popularity for pelvic reconstruction due to its flexible features in surgery [ 13 ].…”

Biomechanical analysis and clinical observation of 3D-printed acetabular prosthesis for the acetabular reconstruction of total hip arthroplasty in Crowe III hip dysplasia

“…All models being analyzed were assumed to be continuous, isotropic, and with homogeneous linear elastic materials. The model was re-imported into Mimics 21, and material assignments were assigned according to the corresponding areas of the cortical and cancellous bone obtained by CT scanning ( Guo et al, 2022 ) ( Figure 2A ). Table 1 lists the parameters of various materials ( Fu et al, 2018 ).…”

Design of 3D-printed prostheses for reconstruction of periacetabular bone tumors using topology optimization

“…This field encompasses procedures such as massive pelvis allografts ( Matejovsky et al, 2006 ; Ayvaz et al, 2014 ) and extracorporeally irradiated autografts ( Wafa et al, 2014 ). Contemporary prosthetic options for reconstruction comprise ice-cream cone prostheses ( Barrientos-Ruiz et al, 2017 ; Fujiwara et al, 2021 ), saddle-shaped prostheses ( Aboulafia et al, 1995 ; Kitagawa et al, 2006 ; Danışman et al, 2016 ), modular hemipelvis prostheses ( Ji et al, 2010 ; Li et al, 2022 ), and three-dimensionally printed (3D-printed) prostheses ( Wang et al, 2020 ; Zhu et al, 2021 ; Guo et al, 2022 ). Most of these biological reconstruction techniques have yielded encouraging outcomes in subsequent assessments.…”

“…Nevertheless, when addressing bone tumors situated in intricate locales, 3D-printed prostheses offer enhanced precision and temporal efficiency. Consequently, its application within the realm of pelvis tumor treatment has observed a progressive upsurge ( Wang et al, 2020 ; Guo et al, 2022 ; Zhu et al, 2022 ).…”