IIIE   20352
INSTITUTO DE INVESTIGACIONES EN INGENIERIA ELECTRICA "ALFREDO DESAGES"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Prediction of vertebral body stiffness in patients with multiple myeloma using qCT-based finite element models
Autor/es:
GRAEME CAMPBELL; CHRISTIAN GRAEFF; SARAH GIRAVENT; FELIX THOMSEN; JAIME PEÑA; A WULFF; A GÜNTHER; CLAUS-C. GLÜER; JAN BORGGREFE
Lugar:
Lisbon
Reunión:
Congreso; European Calcified Tissue Society Congress 2013; 2013
Institución organizadora:
European Calcified Tissue Society
Resumen:
Multiple myeloma (MM) is associated with lytic bone
destruction leading to high fracture incidence in the vertebrae.
Accurate assessment of fracture risk is required for physicians to
determine the necessity for surgery. This risk is currently determined
by examining lesion size or number; however, this method does not
consider the biomechanical attributes of the bone. Finite element (FE)
modelling can simulate mechanical loading on vertebral bodies, and
estimate mechanical integrity, potentially giving a more reliable
prediction of fracture risk.
Vertebral
quantitative computed tomography (qCT) scans were evaluated in 60 MM
patients, 30 with fracture and 30 without. From the images, in-house
software was used to generate linear FE models that consisted of
tetrahedral elements with transverse isotropic material properties.
Elemental stiffness was calculated from local bone mineral density (BMD)
values. Uniaxial compression was simulated to a deformation of 1 mm and
the apparent level stiffness determined. t-Tests were used to compare stiffness between fracture and non-fracture groups, and standardized odds ratios (normalized to S.D.)
and 95% CIs were calculated. Using structural and mineral data from
previous work, correlations between stiffness and bone volume ratio
(BV/TV), trabecular BMD (tBMD), trabecular separation (TbSp), and
cortical BMD (cBMD) were determined.
Vertebral body stiffness in patients with fracture was significantly lower than those without (16.3 vs 23.4 kN/mm, P=0.012), and the age-adjusted logistic regression revealed an OR/S.D. of 3.57 (1.17?10.84). Significant correlations between stiffness and tBMD (R=0.6639, P<0.001), Tb.Sp (R=−0.5255, P<0.001) and cBMD (R=0.52, P<0.001) were observed.
Reduced
vertebral stiffness was associated with fracture prevalence, indicating
that this is a potential parameter for the assessment of fracture risk
in patients with MM. Both trabecular (tBMD, Tb.Sp) and cortical (cBMD)
parameters significantly correlated with stiffness. Future work will
involve the development of nonlinear FE models in order to predict
vertebral strength.