TY - JOUR
T1 - Predicting the subject-specific primary stability of cementless implants during pre-operative planning
T2 - Preliminary validation of subject-specific finite-element models
AU - Reggiani, B.
AU - Cristofolini, L.
AU - Varini, E.
AU - Viceconti, M.
PY - 2007
Y1 - 2007
N2 - Pre-operative planning help the surgeon in taking the proper clinical decision. The ultimate goal of this work is to develop numerical models that allow the surgeon to estimate the primary stability during the pre-operative planning session. The present study was aimed to validate finite-element (FE) models accounting for patient and prosthetic size and position as planned by the surgeon. For this purpose, the FE model of a cadaveric femur was generated starting from the CT scan and the anatomical position of a cementless stem derived by a skilled surgeon using a pre-operative CT-based planning simulation software. In-vitro experimental measurements were used as benchmark problem to validate the bone-implant relative micromotions predicted by the patient-specific FE model. A maximum torque in internal rotation of 11.4 Nm was applied to the proximal part of the hip stem. The error on the maximum predicted micromotion was 12% of the peak micromotion measured experimentally. The average error over the entire range of applied torques was only 7% of peak measurement. Hence, the present study confirms that it is possible to accurately predict the level of primary stability achieved for cementless stems using numerical models that account for patient specificity and surgical variability.
AB - Pre-operative planning help the surgeon in taking the proper clinical decision. The ultimate goal of this work is to develop numerical models that allow the surgeon to estimate the primary stability during the pre-operative planning session. The present study was aimed to validate finite-element (FE) models accounting for patient and prosthetic size and position as planned by the surgeon. For this purpose, the FE model of a cadaveric femur was generated starting from the CT scan and the anatomical position of a cementless stem derived by a skilled surgeon using a pre-operative CT-based planning simulation software. In-vitro experimental measurements were used as benchmark problem to validate the bone-implant relative micromotions predicted by the patient-specific FE model. A maximum torque in internal rotation of 11.4 Nm was applied to the proximal part of the hip stem. The error on the maximum predicted micromotion was 12% of the peak micromotion measured experimentally. The average error over the entire range of applied torques was only 7% of peak measurement. Hence, the present study confirms that it is possible to accurately predict the level of primary stability achieved for cementless stems using numerical models that account for patient specificity and surgical variability.
KW - Cementless stem
KW - Micromotion
KW - Pre-operative planning
KW - Primary stability
KW - Subject-specific FE model
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U2 - 10.1016/j.jbiomech.2006.10.042
DO - 10.1016/j.jbiomech.2006.10.042
M3 - Article
C2 - 17229427
AN - SCOPUS:34447625412
VL - 40
SP - 2552
EP - 2558
JO - Journal of Biomechanics
JF - Journal of Biomechanics
SN - 0021-9290
IS - 11
ER -