Initial stability of a highly porous titanium cup in an acetabular bone defect model

Purpose. The purpose of this study was to establish the finite element analysis (FEA) model of acetabular bone defect reconstructed by 3D printed Ti6Al4V augment and TM augment and further to analyze the stress distribution and clinical safety of augments, screws, and bones.Methods. The FEA model of acetabular bone defect reconstructed by 3D printed Ti6Al4V augment was established by the CT data of a patient with Paprosky IIIA defect. The von Mises stresses of augments, screws, and bones were analyzed by a single-legged stance loading applied in 3 increments (500 N, 2000 N, and 3000 N).Results. The peak von Mises stresses under the maximal loading in the 3D printed augments, screws, and cortical bone were less than the yield strength of the corresponding component. However, the peak stress in the bone was greater than the yield strength of cancellous bone under walking or jogging loading. And under the same loading, the peak compressive and shear stresses in bone contact with TM augment were larger than these with 3D printed augment.Conclusions. The FEA results show that all the components will be intact under single-legged standing. However, partial cancellous bone contacted with 3D printed augment and screws will lose efficacy under walking or jogging load. So we recommend that patients can stand under full bearing, but can not walk or jog immediately after surgery.

Download Full-text

In Vivo Reconstruction of the Acetabular Bone Defect by the Individualized Three-Dimensional Printed Porous Augment in a Swine Model

BioMed Research International ◽

10.1155/2020/4542302 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Jun Fu ◽

Yi Xiang ◽

Ming Ni ◽

Xiaojuan Qu ◽

Yonggang Zhou ◽

...

Keyword(s):

Compressive Strength ◽

Elastic Modulus ◽

Bone Defect ◽

Bone Ingrowth ◽

Structural Parameters ◽

Three Dimensional ◽

Acetabular Bone ◽

Acetabular Bone Defect ◽

3D Printed ◽

Matching Degree

Background and Purpose. This study established an animal model of the acetabular bone defect in swine and evaluated the bone ingrowth, biomechanics, and matching degree of the individualized three-dimensional (3D) printed porous augment. Methods. As an acetabular bone defect model created in Bama miniswine, an augment individually fabricated by 3D print technique with Ti6Al4V powders was implanted to repair the defect. Nine swine were divided into three groups, including the immediate biomechanics group, 12-week biomechanics group, and 12-week histological group. The inner structural parameters of the 3D printed porous augment were measured by scanning electron microscopy (SEM), including porosity, pore size, and trabecular diameter. The matching degree between the postoperative augment and the designed augment was assessed by CT scanning and 3D reconstruction. In addition, biomechanical properties, such as stiffness, compressive strength, and the elastic modulus of the 3D printed porous augment, were measured by means of a mechanical testing machine. Moreover, bone ingrowth and implant osseointegration were histomorphometrically assessed. Results. In terms of the inner structural parameters of the 3D printed porous augment, the porosity was 55.48 ± 0.61 % , pore size 319.23 ± 25.05 μ m , and trabecular diameter 240.10 ± 23.50 μ m . Biomechanically, the stiffness was 21464.60 ± 1091.69 N / mm , compressive strength 231.10 ± 11.77 MPa , and elastic modulus 5.35 ± 0.23 GPa , respectively. Furthermore, the matching extent between the postoperative augment and the designed one was up to 91.40 ± 2.83 % . Besides, the maximal shear strength of the 3D printed augment was 929.46 ± 295.99 N immediately after implantation, whereas the strength was 1521.93 ± 98.38 N 12 weeks after surgery ( p = 0.0302 ). The bone mineral apposition rate (μm per day) 12 weeks post operation was 3.77 ± 0.93 μ m / d . The percentage bone volume of new bone was 22.30 ± 4.51 % 12 weeks after surgery. Conclusion. The 3D printed porous Ti6Al4V augment designed in this study was well biocompatible with bone tissue, possessed proper biomechanical features, and was anatomically well matched with the defect bone. Therefore, the 3D printed porous Ti6Al4V augment possesses great potential as an alternative for individualized treatment of severe acetabular bone defects.

Download Full-text

3D Printing Hip Prostheses Offer Accurate Reconstruction, Stable Fixation, and Functional Recovery for Revision Total Hip Arthroplasty with Complex Acetabular Bone Defect

Engineering ◽

10.1016/j.eng.2020.04.013 ◽

2020 ◽

Vol 6 (11) ◽

pp. 1285-1290

Author(s):

Yongqiang Hao ◽

Lei Wang ◽

Wenbo Jiang ◽

Wen Wu ◽

Songtao Ai ◽

...

Keyword(s):

3D Printing ◽

Total Hip Arthroplasty ◽

Bone Defect ◽

Functional Recovery ◽

Hip Arthroplasty ◽

Revision Total Hip Arthroplasty ◽

Stable Fixation ◽

Acetabular Bone ◽

Hip Prostheses ◽

Acetabular Bone Defect

Download Full-text

Acetabular custom-made implants for severe acetabular bone defect in revision total hip arthroplasty: a systematic review of the literature

Archives of Orthopaedic and Trauma Surgery ◽

10.1007/s00402-020-03334-5 ◽

2020 ◽

Vol 140 (3) ◽

pp. 415-424 ◽

Cited By ~ 5

Author(s):

Francesco Chiarlone ◽

Andrea Zanirato ◽

Luca Cavagnaro ◽

Mattia Alessio-Mazzola ◽

Lamberto Felli ◽

...

Keyword(s):

Systematic Review ◽

Total Hip Arthroplasty ◽

Bone Defect ◽

Hip Arthroplasty ◽

Revision Total Hip Arthroplasty ◽

Review Of The Literature ◽

Acetabular Bone ◽

Total Hip ◽

Acetabular Bone Defect ◽

Custom Made

Download Full-text

Glass-Ceramic implant in acetabular bone defect: An experimental study

Journal of Applied Biomaterials ◽

10.1002/jab.770030402 ◽

1992 ◽

Vol 3 (4) ◽

pp. 245-249 ◽

Cited By ~ 3

Author(s):

Satoru Yoshii ◽

Takao Yamamuro ◽

Takashi Nakamura ◽

Masanori Oka ◽

Haruki Takagi ◽

...

Keyword(s):

Experimental Study ◽

Bone Defect ◽

Glass Ceramic ◽

Acetabular Bone ◽

Acetabular Bone Defect ◽

Ceramic Implant

Download Full-text

Stress analysis of a Burch-Schneider cage in an acetabular bone defect: A case study

Reconstructive Review ◽

10.15438/rr.6.1.141 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 1

Author(s):

Katrien Plessers ◽

Hans Mau

Keyword(s):

Bone Defect ◽

Long Term Results ◽

Element Analysis ◽

Large Defect ◽

Acetabular Bone ◽

Acetabular Bone Defect ◽

Increased Risk ◽

Acetabular Bone Defects ◽

Von Mises ◽

Von Mises Stresses

Burch-Schneider cages are often used for the treatment of acetabular bone defects. In several clinical studies these cages have shown good mid- to long-term results. However, a higher failure rate has been reported in large Paprosky IIIB defects compared with smaller Paprosky II-IIIA defects. This study aims to investigate the effect of cage support on cage failure by means of finite element analysis. The Von Mises stresses in both the implant and the bone are analyzed for a Burch-Schneider cage used in the following scenarios: (1) a large acetabular bone defect, (2) a small acetabular bone defect and (3) a large acetabular bone defect in combination with a reinforcement plate. The results show that implant and bone stresses are higher in the large defect (99th percentile of 146.6 and 73.5 MPa respectively) than in the small defect (99th percentile of 43.9 and 47.9 MPa respectively). Adding a reinforcement plate to posteriorly support the cage decreases the stresses but not fully compensates for the missing bone support (99th percentile of 93.1 and 55.3 MPa respectively). Since high stresses cause an increased risk for fatigue failure and implant loosening, sufficient implant support is required to reduce the risk of cage failure.

Download Full-text

Reconstruction of Paprosky type III Acetabular Defects by the Three-dimensional Printed Porous Augment: Techniques and Clinical Outcomes of 18 Consecutive Cases

10.21203/rs.3.rs-94006/v1 ◽

2020 ◽

Author(s):

Jun Fu ◽

Ming Ni ◽

Xiang Li ◽

Wei Chai ◽

Libo Hao ◽

...

Keyword(s):

Clinical Outcomes ◽

Bone Defect ◽

Three Dimensional ◽

Acetabular Bone ◽

Type Iii ◽

Acetabular Bone Defect ◽

3D Printed ◽

The Mean ◽

Acetabular Defects

Abstract Background and Purpose: A major challenge posed by primary and revision total hip arthroplasty (THA) is the management of severe acetabular bone defect. Previous surgical techniques have certain limitations in the anatomical reconstruction and accurate match of severe acetabular defects. Until now, reports are scanty on the clinical outcomes of acetabular reconstruction by the three-dimensional (3D) printed porous augments in bone defect patients. This study reported the clinical outcomes of reconstruction of Paprosky type III acetabular defects by 3D printed porous augments.Methods: 18 patients with Paprosky type III acetabular defects receiving reconstructive surgery by 3D printed porous augments were included in current study. Their data, including general information, intra-operative findings, imaging results, functional scores and complications were retrospectively analyzed.Results: The mean follow-up time lasted 33.3 ± 2.0 (24-56) months. The average limb-length discrepancy (LLD) was 31.7 ± 4.2 (3-59) mm preoperatively, 7.7 ± 1.4 (1-21) mm postoperatively (p<0.0001) and 7.5 ± 1.2 (0-18) mm at the latest follow-up. The mean vertical position of hip center of rotation (HCOR) from the inter teardrop line changed from preoperative 50.7 ± 3.9 (23.3-75.3) mm to postoperative 22.9 ± 1.9 (10.1-40.3) mm (p<0.0001), with the latest follow-up revealing an HCOR of 22.3 ± 1.7 (11.0-40.5) mm. Follow-up study showed that no hip had radiolucencies and radiological loosening of the acetabular components and augment. The average HHS improved from 40.3 ± 4.5 (10.5-71) before operation to 88.4 ± 1.9 (75-97) at the last follow-up (p<0.0001). Moreover, follow-up exhibited that no periprosthetic joint infection, hip dislocation, fracture and re-revision occurred. Conclusion: Surgical treatment of Paprosky type III acetabular defect with 3D printed porous augment was simple, achieved good match between porous augment and the defect bone surface and the acetabular component, ideally restored LLD and HCOR after operation, significantly improved HHS score and attained good early clinical outcomes. It is a promising personalized solution for patients with severe acetabular bone defect.

Download Full-text

The experimental study of tissue integration into porous titanium implants

Hip International ◽

10.1177/1120700020943481 ◽

2020 ◽

pp. 112070002094348

Author(s):

Rashid Tikhilov ◽

Igor Shubnyakov ◽

Alexey Denisov ◽

Vladimir Konev ◽

Iosif Gofman ◽

...

Keyword(s):

Tensile Strength ◽

Bone Defect ◽

Porous Titanium ◽

Titanium Implants ◽

Control Group ◽

Additive Technology ◽

Tissue Integration ◽

3D Printed ◽

Tissue Attachment ◽

Highly Porous

Introduction: Due to a lack of uniform shapes and sizes of bone defects in hip and knee joint pathology, their fixing could benefit from using individually manufactured 3D-printed highly porous titanium implants. The objective of this study was to evaluate the extent of bone and muscle tissue integration into porous titanium implants manufactured using additive technology. Materials and methods: Porous and non-porous titanium plates were implanted into the latissimus dorsi muscle and tibia of 9 rabbits. On days 1, 60 and 90 animals were examined with x-rays. On day 60 histological tests were carried out. On day 90 the tensile strength at the implant-tissue interface was tested. Results: Histological analysis of muscle samples with porous titanium implants showed integration of connective tissue and blood vessels into the pores. Bone defect analysis demonstrated bone ingrowth into the pores of titanium with a minimal amount of fibrous tissue. The tensile strength of the muscular tissue attachment to the porous titanium was 28 (22–30) N which was higher than that of the control group 8.5 (5–11) N. Bone tissue attachment strength was 148 (140–152) N in the experimental group versus 118 (84–122) N in the control group. Conclusions: Using additive technology in manufacturing 3D-printed highly porous titanium implants improves bone and muscle integration compared with the non-porous material of the control group. This could be a promising approach to bone defect repair in revision and reconstruction surgery.

Download Full-text