High day-to-day repeatability of lower extremity muscle activation patterns and joint biomechanics of dual-belt treadmill gait: A reliability study in healthy young adults.

Purpose: The reliability of lower extremity muscle activation patterns has not been clearly studied in a dual-belt instrumented treadmill environment. The primary study objective was to quantify the day-to-day reliability of quadriceps, hamstrings, gastrocnemius and gluteus medius activation patterns in healthy young adult gait. Secondarily, the reliability of spatiotemporal, and knee/hip motion and moment-based gait outcomes was assessed.

Knee moment outcomes using inverse dynamics and the cross product function in moderate knee osteoarthritis gait: A comparison study.

Inverse dynamics are the cornerstone of biomechanical assessments to calculate knee moments during walking. In knee osteoarthritis, these outcomes have been used to understand knee pathomechanics, but the complexity of an inverse dynamic model may limit the uptake of joint moments in some clinical and research structures. The objective was to determine whether discrete features of the sagittal and frontal plane knee moments calculated using inverse dynamics compare to knee moments calculated using a cross product function.

Intra-articular pressures and joint mechanics: should we pay attention to effusion in knee osteoarthritis?

What factors play a role to ensure a knee joint does what it should given the demands of moving through the physical environment? This paper aims to probe the hypothesis that intra-articular joint pressures, once a topic of interest, have been left aside in contemporary frameworks in which we now view knee joint function. The focus on ligamentous deficiencies and the chondrocentric view of osteoarthritis, while important, have left little attention to the consideration of other factors that can impair joint function across the lifespan. Dynamic knee stability is required during every step we take.

Sit-to-stand transfer mechanics in healthy older adults: a comprehensive investigation of a portable lifting-seat device.

Purpose: To evaluate lower extremity mechanics and muscle activation associated with the sit-to-stand transfer using a portable lifting-seat device and to compare these data to an unassisted transfer in healthy young and older adults.

Methods: Bilateral lower extremity and low back musculature electromyography, three-dimensional leg and trunk motion, and ground reaction forces were recorded from 10 young (mean age = 25) and 10 older (mean age = 69) adults during five trials of (i) no assist and (ii) assisted transfers. Data were time normalized to represent the period of seat-off to standing.

Hip abductor function in individuals with medial knee osteoarthritis: Implications for medial compartment loading during gait.

Background: Hip abductor muscles generate moments of force that control lower extremity frontal plane motion. Strengthening these muscles has been a recent trend in therapeutic intervention studies for knee osteoarthritis. The current study investigated the relationship between hip abductor muscle function (strength and activation) and the net external knee adduction moment during gait in those with medial compartment knee osteoarthritis.

Explaining the hip adduction moment variability during gait: Implications for hip abductor strengthening.

Background: There is emerging interest in hip abductor function during gait and its potential relationship to knee joint pathology. During gait, the hip abductor muscles are primarily responsible for generating moments of force to control frontal plane movement. The current study investigated the relationship between hip abductor muscle function and frontal plane hip moments of force during gait.