Flexible multibody simulation approach in the analysis of tibial strain during walking

Abstract

Strains within the bone tissue play a major role in bone (re)modeling. These small strains can be assessed using experimental strain gage measurements, which are challenging and invasive. Further, the strain measurements are, in practise, limited to certain regions of superficial bones only, such as the anterior surface of the tibia. In this study, tibial strains occurring during walking were estimated using a numerical approach based on flexible multibody dynamics. In the introduced approach, a lower body musculoskeletal model was developed by employing motion capture data obtained from walking at a constant velocity. The motion capture data were used in inverse dynamics simulation to teach the muscles in the model to replicate the motion in forward dynamics simulation. The maximum and minimum tibial principal strains predicted by the model were 490 and -588 microstrain, respectively, which are in line with literature values from in vivo measurements. In conclusion, the non-invasive flexible multibody simulation approach may be used as a surrogate for experimental bone strain measurements and thus be of use in detailed strain estimations of bones in different applications.

From mechanical stimulus to bone formation: A review

“…However, physical activities, such as sprinting or running in a zigzag, forward jumping and vertical dropping, may increase bone formation if we consider these data to be physiological values and 1000 μɛ at 1 Hz cyclic mechanical loading is assumed as the MESm [101][102][103]. Importantly, only tibiae shaft measurements were considered, and conclusions based on these data should not be extrapolated to the spine and may or may not be valid for other bones in the body [98,[104][105][106].…”

The Effect of Drop-Landing Height on Tibia Bone Strain

“…Thus, the sample size chosen in this study was justified. In fact, similar studies in the literature used sample sizes from 1 to 4 [19] [23]. Second, all our participants met the US Army enlistment standards.…”

“…Material properties were assigned assuming that bone is transversely isotropic within the ranges of strain we evaluated [20] [21] [22]. A Young's Modulus of 17 GPa and Poisson's Ratio of 0.3 were used based on previously reported values [23]. The tibia bone model prepared in MD Marc was then converted into a modal neutral file (MNF) representing a flexible tibia.…”

“…The right side of the model was actuated by 17 muscles, while the left side was controlled using motion-replicating servo controlled joints. The kinematics collected during drop-landing tasks were used to drive the musculoskeletal model with an inverse dynamics algorithm while muscles' shortening/lengthening patterns were recorded [23]. Subsequently, kinematic constrains were removed and a forward dynamics simulation was performed with muscles serving as actuators and experimental ground reaction forces applied to replicate the drop-landing motion.…”

Dynamical analysis and design of active orthoses for spinal cord injured subjects by aesthetic and energetic optimization

“…Multibody system dynamics (MSD) techniques are potentially very powerful in this field and there are many contributions from the MSD community to this challenging problem [1,2,3,4]. Among other approaches, parameter optimization techniques have been frequently used for motion synthesis of biped robots [5].…”