Dynamic joint stiffness is a dynamic, nonlinear relationship between the position of a joint and the torque acting about it, which can be used to describe the biomechanics of the joint and associated limb(s). This paper models and quantifies changes in ankle dynamic stiffness and its individual elements, intrinsic and reflex stiffness, in healthy human subjects during isometric, time-varying (T...

To better understand methodological factors that alter landings strategies, we compared sagittal plane joint energetics during the initial landing phase of drop jumps (DJ) vs. drop landings (DL), and when shod vs. barefoot. Surface electromyography, kinematic and kinetic data were obtained on 10 males and 10 females during five consecutive drop landings and five consecutive drop jumps (0.45m) w...

A stiff thin film bonded to a pre-strained, compliant substrate wrinkles into a sinusoidal form upon release of the pre-strain. Many analytical models developed for the critical pre-strain for wrinkling assume that the substrate is semi-infinite. This critical pre-strain is actually much smaller than that for a substrate with finite thickness (Ma Y et al. 2016 Adv. Funct. Mater. (doi:10.1002/ad...

A generalised method for the identification of the parameters which describe the dynamic properties of media between coupled substructures using measured FRFs is presented in this paper. The effort is mainly focused on the development of this generalised method and the improvement of its constituent algorithms. The method presented here is more general and more practical in some aspects when co...

PURPOSE A substantial amount of rotational energy is lost at the metatarsophalangeal joint during running and jumping. We hypothesized that the lost energy could be decreased by increasing the bending stiffness of shoe midsoles. The purposes of this investigation were to determine the influence of stiff shoe midsoles on changes in lower extremity joint power during running and jumping and to de...

OBJECTIVE It is still not clarified whether spasticity contributes to impairments of gait function. Here we compared biomechanical measures of muscle weakness and stiffness of ankle muscles to impairments of gait function in adults with cerebral palsy (CP). METHODS Twenty-four adults with CP (mean age 34.3, range 18-57 years) and fifteen healthy age-matched controls were biomechanically measu...

Extensive limb lengthening may be indicated in achondroplastic patients who wish to achieve a height within the normal range for their population. However, increasing the magnitude of lengthening is associated with further complications particularly adjacent joint stiffness and fractures. We studied the relationship between the magnitude of femoral lengthening and callus pattern, adjacent joint...

BACKGROUND Despite increasing attention on fixation of a soft tissue anterior cruciate ligament graft in the tibia, there have been no studies on the use of a bone dowel as a joint line fixation device for promoting fixation properties, especially stiffness at the time of implantation. PURPOSE To determine whether compacting a bone dowel into the tibial tunnel improves fixation stiffness, yie...

OBJECTIVE To assess the clinical evidence for bee venom acupuncture (BVA) for rheumatoid arthritis (RA). DESIGN Systematic review of randomised controlled trials (RCTs). SETTING We searched 14 databases up to March 2014 without a language restriction. PARTICIPANTS Patients with RA. INTERVENTION BVA involved injecting purified, diluted BV into acupoints. We included trials on BVA used al...

OBJECTIVE Individuals experiencing low back pain often present clinically with intervertebral joint dysfunction. The purpose of this study was to determine whether relative changes in stiffness at a single spinal joint alters neural responsiveness of lumbar muscle spindles to either vertebral movement or position. METHODS Muscle spindle discharge was recorded in response to 1mm L6 ramp and ho...