This paper compares two methods proposed in literature [1,2] to calculate the functional knee axis of rotation (fAoR). Calculations are based on 3D motion data based on data during dynamometer processed using Kalman Smoothing [3]. fAoRs are validated with equivalent axes (EA) based on static MR-imaging data. Both methods are combined with a knee motion model (KMY) [4], widely used in the study ...

A prospective randomized study was conducted to determine if a design change in the articular surface geometry introduced in the Optetrak total knee to increase prosthetic joint conformity and further reduce polyethylene stress had any impact on implant survival, particularly when the all-polyethylene version of the implant was used. Forty-seven patients undergoing bilateral simultaneous total ...

The spring-mass model is a valid fundament to understand global dynamics of fast legged locomotion under gravity. The underlying concept of elasticity, implying leg stiffness as a crucial parameter, is also found on lower motor control levels, i.e. in muscle-reflex and muscle-tendon systems. Therefore, it seems reasonable that global leg stiffness emerges from local elasticity established by ap...

Robust preclinical test methods involving tribological simulations are required to investigate and understand the tribological function of osteochondral repair interventions in natural knee tissues. The aim of this study was to investigate the effects of osteochondral allograft implantation on the local tribology (friction, surface damage, wear and deformation) of the tissues in the natural kne...

BACKGROUND Laterally wedged insoles are widely applied in the conservative treatment for medial knee osteoarthritis. Experimental studies have been conducted to understand the effectiveness of such an orthotic intervention. However, the information was limited to the joint external loading such as knee adduction moment. The internal stress distribution is difficult to be obtained from in vivo e...

Articular cartilages and menisci are generally considered to be elastic in the published human knee models, and thus the fluid-flow dependent response of the knee has not been explored using finite element analysis. In the present study, the fluid pressure and site-specific collagen fiber orientation in the cartilages and menisci were implemented into a finite element model of the knee using fi...

BACKGROUND Articular geometry of knee implant has a competing impact on kinematics and contact mechanics of total knee arthroplasty (TKA) such that geometry with lower contact pressure will impose more constraints on knee kinematics. The geometric parameters that may cause this competing effect have not been well understood. This study aimed to quantify the underlying relationships between impl...

The calibration of a LE Ge detector system has been performed at CIEMAT Whole Body Counter for the assessment of Am in skull and knee. The facility counts with a Cohen phantom simulating a human head with 1000 Bq of Americium homogeneously distributed in the bone equivalent material. Measurements of the LE Ge system with the skull phantom were carried out in an optimisation study of counting ef...

purpose: over the past 20 years, the center of pressure (cop) has been commonly used as an index of postural stability in standing. while many studies investigated cop excursions in patients with knee osteoarthritis and healthy individuals, no comprehensive analysis of the differences in their postural sway pattern exists. the present study aimed to review the previously published studies conce...

Since meniscal geometry affects the cartilage contact pressures, it is essential to carefully define the geometry of the synthetic meniscal implant that we developed. Recently, six independent modes of size- and shape-related geometry variation were identified through 3D statistical shape modeling (SSM) of the medial meniscus. However, this model did not provide information on the functional im...