title: Patient-specific Hip Fracture Strength Assessment with Microstructural MR Imaging-based Finite Element Modeling.
abstract: Purpose To describe a nonlinear finite element analysis method by using magnetic resonance (MR) images for the assessment of the mechanical competence of the hip and to demonstrate the reproducibility of the tool. Materials and Methods This prospective study received institutional review board approval and fully complied with HIPAA regulations for patient data. Written informed consent was obtained from all subjects. A nonlinear finite element analysis method was developed to estimate mechanical parameters that relate to hip fracture resistance by using MR images. Twenty-three women (mean age ± standard deviation, 61.7 years ± 13.8) were recruited from a single osteoporosis center. To thoroughly assess the reproducibility of the finite element method, three separate analyses were performed: a test-retest reproducibility analysis, where each of the first 13 subjects underwent MR imaging on three separate occasions to determine longitudinal variability, and an intra- and interoperator reproducibility analysis, where a single examination was performed in each of the next 10 subjects and four operators independently performed the analysis two times in each of the subjects. Reproducibility of parameters that reflect fracture resistance was assessed by using the intraclass correlation coefficient and the coefficient of variation. Results For test-retest reproducibility analysis and inter- and intraoperator analyses for proximal femur stiffness, yield strain, yield load, ultimate strain, ultimate load, resilience, and toughness in both stance and sideways-fall loading configurations each had an individual median coefficient of variation of less than 10%. Additionally, all measures had an intraclass correlation coefficient higher than 0.99. Conclusion This experiment demonstrates that the finite element analysis model can consistently and reliably provide fracture risk information on correctly segmented bone images.©RSNA, 2016 Online supplemental material is available for this article.
authors.affiliation: From the Departments of Radiology (C.S.R., B.T.N., E.A.K., R.M.) and Orthopaedic Surgery (C.S.R.), University of Pennsylvania, 3400 Spruce St, 1 Founders Building, Philadelphia, PA 19104; and Department of Radiology, Center for Biomedical Imaging (A.H., G.C.), Department of Orthopaedic Surgery, Hospital for Joint Diseases (A.R., S.V.), and Osteoporosis Center, Hospital for Joint Diseases (S.H.), NYU Langone Medical Center, New York, NY.
authors.forename: Chamith S
authors.initials: CS
authors.lastname: Rajapakse
authors.affiliation: From the Departments of Radiology (C.S.R., B.T.N., E.A.K., R.M.) and Orthopaedic Surgery (C.S.R.), University of Pennsylvania, 3400 Spruce St, 1 Founders Building, Philadelphia, PA 19104; and Department of Radiology, Center for Biomedical Imaging (A.H., G.C.), Department of Orthopaedic Surgery, Hospital for Joint Diseases (A.R., S.V.), and Osteoporosis Center, Hospital for Joint Diseases (S.H.), NYU Langone Medical Center, New York, NY.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Hotca
authors.affiliation: From the Departments of Radiology (C.S.R., B.T.N., E.A.K., R.M.) and Orthopaedic Surgery (C.S.R.), University of Pennsylvania, 3400 Spruce St, 1 Founders Building, Philadelphia, PA 19104; and Department of Radiology, Center for Biomedical Imaging (A.H., G.C.), Department of Orthopaedic Surgery, Hospital for Joint Diseases (A.R., S.V.), and Osteoporosis Center, Hospital for Joint Diseases (S.H.), NYU Langone Medical Center, New York, NY.
authors.forename: Benjamin T
authors.initials: BT
authors.lastname: Newman
authors.affiliation: From the Departments of Radiology (C.S.R., B.T.N., E.A.K., R.M.) and Orthopaedic Surgery (C.S.R.), University of Pennsylvania, 3400 Spruce St, 1 Founders Building, Philadelphia, PA 19104; and Department of Radiology, Center for Biomedical Imaging (A.H., G.C.), Department of Orthopaedic Surgery, Hospital for Joint Diseases (A.R., S.V.), and Osteoporosis Center, Hospital for Joint Diseases (S.H.), NYU Langone Medical Center, New York, NY.
authors.forename: Austin
authors.initials: A
authors.lastname: Ramme
authors.affiliation: From the Departments of Radiology (C.S.R., B.T.N., E.A.K., R.M.) and Orthopaedic Surgery (C.S.R.), University of Pennsylvania, 3400 Spruce St, 1 Founders Building, Philadelphia, PA 19104; and Department of Radiology, Center for Biomedical Imaging (A.H., G.C.), Department of Orthopaedic Surgery, Hospital for Joint Diseases (A.R., S.V.), and Osteoporosis Center, Hospital for Joint Diseases (S.H.), NYU Langone Medical Center, New York, NY.
authors.forename: Shaleen
authors.initials: S
authors.lastname: Vira
authors.affiliation: From the Departments of Radiology (C.S.R., B.T.N., E.A.K., R.M.) and Orthopaedic Surgery (C.S.R.), University of Pennsylvania, 3400 Spruce St, 1 Founders Building, Philadelphia, PA 19104; and Department of Radiology, Center for Biomedical Imaging (A.H., G.C.), Department of Orthopaedic Surgery, Hospital for Joint Diseases (A.R., S.V.), and Osteoporosis Center, Hospital for Joint Diseases (S.H.), NYU Langone Medical Center, New York, NY.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Kobe
authors.affiliation: From the Departments of Radiology (C.S.R., B.T.N., E.A.K., R.M.) and Orthopaedic Surgery (C.S.R.), University of Pennsylvania, 3400 Spruce St, 1 Founders Building, Philadelphia, PA 19104; and Department of Radiology, Center for Biomedical Imaging (A.H., G.C.), Department of Orthopaedic Surgery, Hospital for Joint Diseases (A.R., S.V.), and Osteoporosis Center, Hospital for Joint Diseases (S.H.), NYU Langone Medical Center, New York, NY.
authors.forename: Rhiannon
authors.initials: R
authors.lastname: Miller
authors.affiliation: From the Departments of Radiology (C.S.R., B.T.N., E.A.K., R.M.) and Orthopaedic Surgery (C.S.R.), University of Pennsylvania, 3400 Spruce St, 1 Founders Building, Philadelphia, PA 19104; and Department of Radiology, Center for Biomedical Imaging (A.H., G.C.), Department of Orthopaedic Surgery, Hospital for Joint Diseases (A.R., S.V.), and Osteoporosis Center, Hospital for Joint Diseases (S.H.), NYU Langone Medical Center, New York, NY.
authors.forename: Stephen
authors.initials: S
authors.lastname: Honig
authors.affiliation: From the Departments of Radiology (C.S.R., B.T.N., E.A.K., R.M.) and Orthopaedic Surgery (C.S.R.), University of Pennsylvania, 3400 Spruce St, 1 Founders Building, Philadelphia, PA 19104; and Department of Radiology, Center for Biomedical Imaging (A.H., G.C.), Department of Orthopaedic Surgery, Hospital for Joint Diseases (A.R., S.V.), and Osteoporosis Center, Hospital for Joint Diseases (S.H.), NYU Langone Medical Center, New York, NY.
authors.forename: Gregory
authors.initials: G
authors.lastname: Chang
mesh_terms: D001696:Biomechanical Phenomena; D005260:Female; D020342:Finite Element Analysis; D006620:Hip Fractures / Q000000981:diagnostic imaging*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results