In vivo tibiofemoral cartilage deformation during the stance phase of gait

Abstract

The knowledge of articular cartilage contact biomechanics in the knee joint is important for understanding the joint function and cartilage pathology. However, the in-vivo tibiofemoral articular cartilage contact biomechanics during gait remains unknown. The objective of this study was to determine the in vivo tibiofemoral cartilage contact biomechanics during the stance phase of treadmill gait. Eight healthy knees were magnetic resonance (MR) scanned and imaged with a dual fluoroscopic system during gait on a treadmill. The tibia, femur and associated cartilage were constructed from the MR images and combined with the dual fluoroscopic images to determine in vivo cartilage contact deformation during the stance phase of gait. Throughout the stance phase of gait, the magnitude of peak compartmental contact deformation ranged between 7% and 23% of the resting cartilage thickness and occurred at regions with thicker cartilage. Its excursions in the anteroposterior direction were greater in the medial tibiofemoral compartment as compared to those in the lateral compartment. The contact areas throughout the stance phase were greater in the medial compartment than in the lateral compartment. The information on in vivo tibiofemoral cartilage contact biomechanics during gait could be used to provide physiological boundaries for in vitro testing of cartilage. Also, the data on location and magnitude of deformation among non-diseased knees during gait could identify where loading and later injury might occur in diseased knees.

Impact of synovial fluid flow on temperature regulation in knee cartilage

“…Regarding the mechanical aspects, our model shows similar fluid flow profiles compared to previous studies (Barker and Seedhom, 2001;Liu et al, 2010;Mow et al, 1984). However, our model has the advantage to show the velocity magnitude in different zone of cartilage, which to our knowledge has not been yet presented.…”

“…The axisymmetric model consisted of femoral and tibial cartilage layers each with the thickness of 4 mm. As the contact area of cartilage (1200 mm 2 ) comparing to its thickness (max 4 mm) is large enough, to simplify the model the articulation shape of the cartilage was neglected (Liu et al, 2010). The cartilage was considered as a poroelastic material.…”

“…This model allows us to quantify the synovial fluid flow inside the cartilage when the cartilage is sinusoidally deformed. Both cartilage layers were deformed at a frequency of 1.5 Hz and a 15% amplitude to simulate gagging when the tibial bone is fully constrained (Liu et al, 2010). A zero pressure boundary condition (p ¼0) was defined at the contact surface of the two cartilages to let the fluid flows in and out of the porous cartilage from the cartilage surface during deformation.…”

Intrinsic viscoelasticity increases temperature in knee cartilage under physiological loading

“…Sinusoidal loading at a frequency of 1 Hz, corresponding to walking frequency, was applied on each sample with 15% strain amplitude. This strain corresponds to the mean value of cartilage deformation during stance phase of gait (Liu et al, 2010). A 5% pre-strain was applied to insure full contact with the sample.…”

Strategies for Improving the Repair of Focal Cartilage Defects

“…Dynamic compression increases likewise glycosaminoglycans deposition [73] and improves the compressive modulus of cartilage grafts [74]. The motivation of using such compressive loading comes from the fact that cartilage deformation up to 15% occurs during direct contact between joint surfaces during normal daily movements, such as walking [75]. Most of the studies relating a dynamic compression used frequencies in the range of 0.01 to 1 Hz with strains of 10, 15 or 20% [76].…”