Tag Archives: MK-5108 (VX-689)

To understand the mechanical consequences of knee injury requires a detailed

To understand the mechanical consequences of knee injury requires a detailed analysis of the effect of that injury about joint contact mechanics during activities of daily living. of this study was to assess the relationship between knee joint contact location as estimated using the image-based WCoP method and a directly measured weighted center of contact (WCoC) method during simulated going for walks. To achieve this goal we created knee specific models of six human being cadaveric knees from magnetic resonance imaging. All knees were then subjected to physiological loads on a knee simulator intended to mimic gait. Knee joint motion was captured using a motion capture system. Knee joint contact tensions were synchronously recorded using a thin electronic sensor throughout gait and used to compute WCoC for the medial and lateral plateaus of each knee. WCoP was determined by combining knee kinematics with the MRI-based knee specific model. Both metrics were compared throughout gait using linear regression. The anteroposterior (AP) location of WCoP was significantly correlated with that of WCoC on both tibial plateaus in all specimens (< 0.01 95 confidence interval of Person’s coefficient > 0) but the correlation was not significant in the mediolateral (ML) direction for 4/6 knees (> 0.05). Our study demonstrates that while the location of joint contact from 3D knee joint contact model using the WCoP method is significantly correlated with the location of actual contact tensions in the AP direction that relationship is less particular in the ML direction. between the tibial and femoral bone surfaces to define the contact point. In this method vertices within the tibial plateau with shorter tibia-femur distances were assigned higher weights and therefore considered more important for determining the location of contact (Anderst and Tashman 2003 Beveridge et al. found that the can detect delicate changes in tibiofemoral contact resulting from combined ligament transection MK-5108 (VX-689) (Beveridge et al. 2013 and a connection between the modified tibiofemoral contact and the degree of cartilage degeneration at the site of contact has also emerged MK-5108 (VX-689) (Anderst and Tashman 2009 Beveridge et al. 2013 Despite this connection the relationship between the estimated location of contact using the method and the actual location of contact experienced from the knee during daily activities has not been quantified. The purpose of this study was to assess the relationship between the tibiofemoral contact location as estimated using the and a for the human being knee during the stance phase of simulated walking. Our hypothesis is definitely that the location of contact as Plau quantified using both methods on each plateau would be significantly correlated throughout the stance phase of gait. MATERIAL AND METHODS Summary To test the hypothesis we produced knee specific models for six cadaveric knees which were then subjected to physiological loads intended to mimic gait. The weighted center of contact was directly measured throughout gait using a thin electronic sensor placed on the tibial plateau as reported in our earlier studies (Gilbert et al. 2013 Wang et al. 2014 Marker-based kinematic analysis of the physical experiment was used as input to the knee-specific in silica MK-5108 (VX-689) models to enable the weighted center of proximity to be computed. Magnetic Resonance Imaging Six human being cadaveric knees with no history of surgery or stress were acquired and stored at ?20°C (Anatomy Gifts Registry) the demographics of which are shown in Table MK-5108 (VX-689) 1. The knees were thawed for 12 hours at space temperature and were then scanned using Magnetic Resonance Imaging (MRI). All scanning was performed on a clinical 3T scanner (GE Healthcare Waukesha WI) using an 8 channel phased array knee coil (Invivo Gainesville FL). A 3D CUBE (Platinum et al. 2007 series was acquired to generate an image dataset for segmentation of the menisci: echo time (TE) = 31 ms repetition time (TR) = 2500 ms echo train size = 35-40 receiver bandwidth (RBW) = ± 41.7 kHz quantity of excitations (NEX) = 0.5 with voxel dimensions: 0.3 × 0.3 × 0.6 mm3. A 3D SPGR with rate of recurrence selective extra fat suppression image series was acquired to section cartilage and osseous geometries: TE = 3.2 ms TR = 13.9 ms RBW = ±41.7 kHz NEX = 2 voxel dimensions = 0.3 × 0.3 × 0.7 mm3. Images were by hand segmented using custom software (Fig. 1a). Notice: the articular cartilage surfaces were extracted so that the knee model could be appropriately aligned with the physical digitization of the articular surfaces (observe section). Number 1 (a) Segmentation of.