Dataset Information

Periacetabular reconstruction with a new endoprosthesis.

ABSTRACT: UNLABELLED: Reconstruction of the Type II pelvic resection is challenging. Currently available reconstructive options have inherent problems including graft and implant failure, pain, poor function, and high major complication rates. The periacetabular reconstruction (PAR) endoprosthesis was designed to be secured with internal fixation and bone cement to the remaining ilium and support a reconstructed acetabulum. This construct potentially avoids the complications of graft or hardware failure, while maintaining early mobilization, comfort, limb lengths, and function. We retrospectively reviewed 25 patients who underwent Type II pelvic resection and reconstruction with the PAR endoprosthesis, analyzing function, complications, and survivorship. The minimum followup was 13 months (mean, 29.4 months; range, 13 to 108 months). We compared the PAR data with the literature for the Mark II saddle endoprosthesis. The PAR's average MSTS score was 20.8 (67%), major complications occurred in 14 (56%), and implant survivorship was 84% at 2 years and 60% at 5 years. The rate of failure at the ilium-saddle interface was lower and implant survivorship higher than those in the published literature for the Mark II saddle. We recommend use of the PAR endoprosthesis for reconstruction of large defects following Type II pelvic resection. The modified saddle design provides greater inherent stability, allowing for faster rehabilitation and improved longevity without increased complications and is an improvement over the currently available saddle prostheses. LEVEL OF EVIDENCE: Level III, retrospective case series. See Guidelines for Authors for a complete description of levels of evidence.

SUBMITTER: Menendez LR

PROVIDER: S-EPMC2758957 | biostudies-other | 2009 Nov

REPOSITORIES: biostudies-other

ACCESS DATA

Similar Datasets

Project description:Background: Prostheses for the reconstruction of periacetabular bone tumors are prone to instigate stress shielding. The purpose of this study is to design 3D-printed prostheses with topology optimization (TO) for the reconstruction of periacetabular bone tumors and to add porous structures to reduce stress shielding and facilitate integration between prostheses and host bone. Methods: Utilizing patient CT data, we constructed a finite element analysis (FEA) model. Subsequent phases encompassed carrying out TO on the designated area, utilizing the solid isotropic material penalization model (SIMP), and this optimized removal area was replaced with a porous structure. Further analyses included preoperative FEA simulations to comparatively evaluate parameters, including maximum stress, stress distribution, strain energy density (SED), and the relative micromotion of prostheses before and after TO. Furthermore, FEA based on patients' postoperative CT data was conducted again to assess the potential risk of stress shielding subsequent to implantation. Ultimately, preliminary follow-up findings from two patients were documented. Results: In both prostheses, the SED before and after TO increased by 143.61% (from 0.10322 to 0.25145 mJ/mm3) and 35.050% (from 0.30964 to 0.41817 mJ/mm3) respectively, showing significant differences (p < 0.001). The peak stress in the Type II prosthesis decreased by 10.494% (from 77.227 to 69.123 MPa), while there was no significant change in peak stress for the Type I prosthesis. There were no significant changes in stress distribution or the proportion of regions with micromotion less than 28 μm before and after TO for either prosthesis. Postoperative FEA verified results showed that the stress in the pelvis and prostheses remained at relatively low levels. The results of follow-up showed that the patients had successful osseointegration and their MSTS scores at the 12th month after surgery were both 100%. Conclusion: These two types of 3D-printed porous prostheses using TO for periacetabular bone tumor reconstruction offer advantages over traditional prostheses by reducing stress shielding and promoting osseointegration, while maintaining the original stiffness of the prosthesis. Furthermore, in vivo experiments show that these prostheses meet the requirements for daily activities of patients. This study provides a valuable reference for the design of future periacetabular bone tumor reconstruction prostheses.

Project description:BackgroundThe 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.MethodsThe 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.ResultsThe 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.ConclusionsPSG + CN has potential advantages in improving the accuracy and safety of acetabular positioning and reconstruction.

Project description:BackgroundFibular hemimelia is a congenital disorder that is characterized by the absence of the fibula that could be either partial or complete. Successful management aims to restore normal weight bearing and normal limb length. The introduction of the Ilizarov method of limb lengthening has provided an attractive alternative to amputation. During lengthening, the tight posterolateral soft-tissue structures, the thick fibrous fibular band, and the shortened Achilles tendon become tighter and transfer a valgus force to the talus and calcaneus, further aggravating the deformity.Questions/purposesWe have developed a strategy to address this in patients with Paley type III fibular hemimelia via ankle reconstruction that provides posterolateral stability and buttressing of the ankle and hind foot by reconstructing the lateral buttress. This is achieved through excision of the fibrous fibular anlage, centralization of the ankle, restoring talocalcaneal coronal alignment, and reconstruction of the lateral malleolus by transplanting the cartilaginous remnant of the lateral malleolus or by crafting a bone block autograft taken from the iliac crest or tibia.MethodsA prospective non-randomized clinical trial included ten ankles in eight patients with fibular hemimelia Paley type III (two patients had bilateral deformity). The patients' ages ranged from 7 to 36 months.ResultsAfter a follow-up ranging from 48 to 96 months, a stable plantigrade foot was achieved in nine ankles; one ankle had residual equinus, five ankles had residual valgus heel, and eight ankles had complete range of motion of the ankle, whereas one patient lost 5° of dorsiflexion. One ankle had equinus deformity.ConclusionsTo achieve satisfactory results, a stable plantigrade foot and ankle is necessary in patients with fibular hemimelia before attempting to equalize limb length discrepancy. It is important to reconstruct the ankle through an extra-articular soft tissue release, anlage resection, osteotomies, and restoring the abnormal talocalcaneal relationship before any attempt to equalize LLD.

Dataset Information

Periacetabular reconstruction with a new endoprosthesis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets