Day-to-day reliability of two different models to quantify knee kinematics in subjects with knee osteoarthritis and healthy controls.

Results from instrumented gait analysis vary between test situations. Subject characteristics and the biomechanical model can influence the total amount of variability. The purpose of this study was to quantify reliability of gait data in general, and with respect to the applied model, and investigated population group.

Comparison of distinctive gait variables using two different biomechanical models for knee joint kinematics in subjects with knee osteoarthritis and healthy controls.

Background: Gait analysis is an important instrument in clinical research and results should be objective. The purpose of this study was to quantify clinical outcomes of two biomechanical models with different anatomical coordinate systems and angle decomposition strategies for knee joint kinematics.

Methods: The study was designed to compare a functional approach and a predictive approach with a single comprehensive marker set.

Day-to-Day consistency of lower extremity kinematics during walking and running.

Before conclusions can be drawn with respect to the quality of adaptations in human gait, the day-to-day consistency of the variables of interest must be known. The present study estimated the day-to-day consistency of kinematic variables collected during barefoot walking and running. Sixteen healthy subjects performed two gait analysis sessions based on skin markers.

Functional units of the human foot.

Functional units in the human foot provide a meaningful basis for subdivisions of the entire foot during gait analysis as well as justified simplifications of foot models. The present study aimed to identify such functional units during walking and slow running. An invasive method based upon reflective marker arrays mounted on intracortical pins was used to register motion of seven foot bones.

Invasive in vivo measurement of rear-, mid- and forefoot motion during walking.

The aim of this work was to use bone anchored external markers to describe the kinematics of the tibia, fibula, talus, calcaneus, navicular, cuboid, medial cuneiform, first and fifth metatarsals during gait. Data were collected from six subjects. There was motion at all the joints studied.

A MR imaging procedure to measure tarsal bone rotations.

Magnetic resonance imaging offers unique insights into three-dimensional foot bone motion. Thereby, adequate devices enabling defined loading and positioning of the foot are needed to profit from this noninvasive procedure. Tarsal bone positions of three healthy subjects were repeatedly measured in a pronated and a supinated foot excursion under bodyweight with a newly developed MR imaging procedure.

Reliability of tarsal bone segmentation and its contribution to MR kinematic analysis methods.

The purpose of this study was to determine the reliability of tarsal bone segmentation based on magnetic resonance (MR) imaging using commercially available software. All tarsal bones of five subjects were segmented five times each by two operators. Volumes and second moments of volume were calculated and used to determine the intra- as well as interoperator reproducibility.

Foot kinematics during walking measured using bone and surface mounted markers.

The aim was to compare kinematic data from an experimental foot model comprising four segments ((i) heel, (ii) navicular/cuboid (iii) medial forefoot, (iv) lateral forefoot), to the kinematics of the individual bones comprising each segment. The foot model was represented using two different marker attachment protocols: (a) markers attached directly to the skin; (b) markers attached to rigid plates mounted on the skin. Bone data were collected for the tibia, talus, calcaneus, navicular, cuboid, medial cuneiform and first and fifth metatarsals (n=6).

Intrinsic foot kinematics measured in vivo during the stance phase of slow running.

An accurate kinematic description of the intrinsic articulations of the foot during running has not previously been presented, primarily due to methodological limitations. An invasive method based upon reflective marker arrays mounted on intracortical pins drilled into the bones was used in this study. Four male volunteers participated as subjects.

Concurrent validity and intrasession reliability of the IDEEA accelerometry system for the quantification of spatiotemporal gait parameters.

The aim of this pilot study was to evaluate concurrent validity and intrasession reliability of the IDEEA (Minisun, Fresno, CA) accelerometry system (and associated software) with force plate measurements for spatiotemporal gait variables recorded during normal walking. Ten healthy individuals were asked to walk at a self-selected comfortable speed, over five multicomponent force plates embedded into the walkway floor. For each trial, spatiotemporal gait parameters (single support time, cadence, speed, step and stride length) obtained by the force plates were compared to those recorded by IDEEA.

Three-dimensional kinematics and kinetics of total knee arthroplasty during level walking using single plane video-fluoroscopy and force plates: a pilot study.

The goal of the study was to simultaneously obtain accurate kinematic and kinetic data from a total knee arthroplasty (TKA) during level walking, by coupling force plate data with the kinematics of TKA measured by a movable video-fluoroscopic system. Kinematic and kinetic information of a TKA is crucial for the improvement of implant designs and for the increased longevity of the implant components. Instrumented gait analysis, with skin mounted marker tracking and force plates, is a well-established method for the acquisition of kinematic and kinetic data of TKA in vivo and for non-invasive estimation of joint function.

Ground reaction forces on stairs: effects of stair inclination and age.

The goals of the study were to compare data of vertical ground reaction force (GRF) parameters during level walking, stair ascent and descent on three different stair inclinations and three different age groups. Twenty healthy subjects of three age groups (young 33.7 years; middle 63.

Gait analysis in patients with idiopathic scoliosis.

Introduction: The goal of this study was to observe scoliotic subjects during level walking to identify asymmetries--which may be related to a neurological dysfunction or the spinal deformity itself-and to correlate these to the severity of the scoliotic curve.

Methods: We assessed the gait pattern of ten females (median age 14.4) with idiopathic scoliosis characterised by a left-lumbar and a right-thoracic curve component.

Effects of shoe sole construction on skeletal motion during running.

Purpose: The purpose of this study was to quantify effects of shoe sole modification on skeletal kinematics of the calcaneus and tibia during the stance phase of running.

Methods: Intracortical bone pins with reflective marker triads were inserted under standard local anesthetic into the calcaneus and tibia of five healthy male subjects. The three-dimensional tibiocalcaneal rotations were determined using a joint coordinate system approach.

Tibiocalcaneal kinematics of barefoot versus shod running.

Barefoot running kinematics has been described to vary considerably from shod running. However, previous investigations were typically based on externally mounted shoe and/or skin markers, which have been shown to overestimate skeletal movements. Thus, the purpose of this study was to compare calcaneal and tibial movements of barefoot versus shod running using skeletal markers.

Movement coupling at the ankle during the stance phase of running.

The purpose of this study was to quantify movement coupling at the ankle during the stance phase of running using bone-mounted markers. Intracortical bone pins with reflective marker triads were inserted under standard local anaesthesia into the calcaneus and the tibia of five healthy male subjects. The three-dimensional rotations were determined using a joint coordinate system approach.

Effects of foot orthoses on skeletal motion during running.

Objective: To quantify the effects of medial foot orthoses on skeletal movements of the calcaneus and tibia during the stance phase in running.

Design: Kinematic effects of medial foot orthoses (anterior, posterior, no support) were tested using skeletal (and shoe) markers at the calcaneus and tibia.

Background: Previous studies using shoe and skin markers concluded that medially placed orthoses control/reduce foot eversion and tibial rotation.

[Sports medicine and rehabilitation. Surface and footwear].

Load on the human body can be influenced by shoes and surfaces which is important both in sports and rehabilitation. The loading which can primarily be influenced are impact situations and friction as well as the stability of the foot. This stability is of main interest in the prevention of pain and injury.

Lateral stability in sideward cutting movements.

Sideward cutting movements occur frequently in sports activities, such as basketball, soccer, and tennis. These activities show a high incidence of injuries to the lateral aspect of the ankle. Consequently, the lateral stability of sport shoes seems important.

Influence of hip and knee joint angles on excitation of knee extensor muscles.

The purpose of this study was to test if (and how) maximal excitation of the knee extensor muscles rectus femoris (RF), vastus lateralis (VL) and vastus medialis (VM) is influenced by knee and/or hip joint angles. Excitation was quantified using surface electromyography. Isometric knee extensions were performed at systematically varying knee and hip joint configurations using a strength testing machine.