Patient-specific mechanical analysis of pedicle screw insertion in simulated osteoporotic spinal bone models derived from medical images
- Author:
Norihiro NISHIDA
1
;
Hidenori SUZUKI
;
Hanvey TETSU
;
Yuki MORISHITA
;
Yogesh KUMARAN
;
Fei JIANG
;
Masahiro FUNABA
;
Kazuhiro FUJIMOTO
;
Yusuke ICHIHARA
;
Takashi SAKAI
;
Junji OHGI
Author Information
- Publication Type:Basic Study
- From:Asian Spine Journal 2024;18(5):621-629
- CountryRepublic of Korea
- Language:English
-
Abstract:
Methods:Male and female patients with computed tomography data were selected. Dimensions of the first thoracic (T1), fourth lumbar (L4), and fifth lumbar (L5) vertebrae were measured, and bone models consisting of the cancellous and cortical bones made from polyurethane foam were created. PS with diameters of 4.5 mm, 5.5 mm, and 6.5 mm were used. T1 PS were 25 mm long, and L4 and L5 PS were 40 mm long. The bone models were secured with cement, and the MIT was measured using a calibrated torque wrench. After MIT testing, the PS head was attached to the machine’s crosshead. POS was then calculated at a crosshead speed of 5 mm/min until failure.
Results:The L4 and L5 were notably larger in female bone models, whereas the T1 vertebra was larger in male bone models. Consequently, the MIT and POS for L4 and L5 were higher in female bone models across all PS diameters than in male bone models. Conversely, the MIT for T1 was higher in male bone models across all PS; however, no significant differences were observed in the POS values for T1 between sexes.
Conclusions:The mechanical properties of the proposed bone models can vary based on the vertebral structure and size. For accurate 3D surgical and mechanical simulations in the creation of custom-made medical devices, bone models must be constructed from patientspecific medical images.
