TY - JOUR
T1 - Wear behaviour in total ankle replacement
T2 - A comparison between an in vitro simulation and retrieved prostheses
AU - Affatato, S.
AU - Taddei, P.
AU - Leardini, A.
AU - Giannini, S.
AU - Spinelli, M.
AU - Viceconti, M.
PY - 2009/10
Y1 - 2009/10
N2 - Background: To minimise wear of the meniscal component in total ankle replacement, a three-component artificial joint has recently been developed. This new prosthesis has convex spherical tibial and anticlastic talar metal components with non-anatomic but ligament-compatible shapes in the sagittal plane, and a fully conforming ultra-high-molecular-weight-polyethylene meniscal component inserted in between. The in vitro wear of meniscal components can be assessed using a four-station joint simulator. The study was aimed at comparing wear patterns obtained in vitro with those observed in implant retrievals with the same design. Methods: The wear tests were run in a joint wear simulator at a frequency of 1.1 Hz for two million cycles. Three bearings within corresponding metal components were subjected to flexion/extension (range 0-58°), anterior-posterior translation (0-5.2 mm), internal-external rotation (-1.9° to +5.7°), and a maximum axial load of 2.6 KN. These conditions were taken from the most recent findings in ankle joint mechanics. Three prostheses of the same type were harvested from patients due to replacement failures not associated with the device, 24, 24 and 9 months, respectively, after implantation. The in vitro worn components and the three retrievals were analysed by using a scanning electron microscope, a Coordinate Measuring Machine, and micro-Raman spectroscopy. Findings: Visual and microscopic observations, analyses, and Raman crystallinity-based measurements showed similarity between the patterns generated experimentally in the wear simulator and those seen in retrievals with similar wear life. Interpretation: A joint wear simulator like the one used in this study, once configured properly, appears to be suitable to assess wear rates also in total ankle prostheses.
AB - Background: To minimise wear of the meniscal component in total ankle replacement, a three-component artificial joint has recently been developed. This new prosthesis has convex spherical tibial and anticlastic talar metal components with non-anatomic but ligament-compatible shapes in the sagittal plane, and a fully conforming ultra-high-molecular-weight-polyethylene meniscal component inserted in between. The in vitro wear of meniscal components can be assessed using a four-station joint simulator. The study was aimed at comparing wear patterns obtained in vitro with those observed in implant retrievals with the same design. Methods: The wear tests were run in a joint wear simulator at a frequency of 1.1 Hz for two million cycles. Three bearings within corresponding metal components were subjected to flexion/extension (range 0-58°), anterior-posterior translation (0-5.2 mm), internal-external rotation (-1.9° to +5.7°), and a maximum axial load of 2.6 KN. These conditions were taken from the most recent findings in ankle joint mechanics. Three prostheses of the same type were harvested from patients due to replacement failures not associated with the device, 24, 24 and 9 months, respectively, after implantation. The in vitro worn components and the three retrievals were analysed by using a scanning electron microscope, a Coordinate Measuring Machine, and micro-Raman spectroscopy. Findings: Visual and microscopic observations, analyses, and Raman crystallinity-based measurements showed similarity between the patterns generated experimentally in the wear simulator and those seen in retrievals with similar wear life. Interpretation: A joint wear simulator like the one used in this study, once configured properly, appears to be suitable to assess wear rates also in total ankle prostheses.
KW - CMM
KW - Raman spectroscopy
KW - SEM
KW - Talar component
KW - Three compartment ankle prosthesis
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U2 - 10.1016/j.clinbiomech.2009.06.006
DO - 10.1016/j.clinbiomech.2009.06.006
M3 - Article
C2 - 19643517
AN - SCOPUS:68749110812
SN - 0268-0033
VL - 24
SP - 661
EP - 669
JO - Clinical Biomechanics
JF - Clinical Biomechanics
IS - 8
ER -