Acquisition, Retention, and Transfer Effects of Landing Training to Increase Foot Progression Angle During Bilateral Drop Landings.

Foot position during landing directly influences knee mechanics. Thus, the purpose of this study was to determine success in practicing, repeating, and transferring a desired foot progression angle (FPA) during landing, as well as changes in knee mechanics. Twenty females were randomly assigned to a control or verbal instruction group.

Effects of Small and Normalized Q-Factor Changes and Knee Alignment on Knee Biomechanics during Stationary Cycling.

Increasing inter-pedal distance (Q-Factor: QF) in cycling increases peak internal knee abduction moments (KAbM). The effect of smaller and normalized changes in QF has not been investigated. The purposes of this study were to examine changes in KAbM with small and normalized increases and whether static knee alignment accounts for any changes in knee biomechanics in cycling.

Bicycle Set-Up Dimensions and Cycling Kinematics: A Consensus Statement Using Delphi Methodology.

Bicycle set-up dimensions and cycling kinematic data are important components of bicycle fitting and cyclist testing protocols. However, there are no guidelines on how bicycles should be measured and how kinematic data should be collected to increase the reliability of outcomes. This article proposes a consensus regarding bicycle set-up dimensions and recommendations for collecting cycling-related kinematic data.

Feasibility of Stationary Cycling with Pedal Force Visual Feedback Post-Total Knee Arthroplasty: Implications for Inter-Limb Deficits in Knee Joint Biomechanics.

The purpose of this study was to assess the biomechanical adaptations prompted by stationary cycling paired with visual feedback of vertical pedal reaction forces during both stationary cycling and overground walking for patients who underwent a total knee arthroplasty (TKA). Specifically, an emphasis on the inter-limb deficits in knee joint biomechanics were examined. Ten patients who underwent a TKA took part in an acute intervention with pre- and post-testing measurements of kinematics (240 Hz) and kinetics (1200 Hz) during stationary cycling and overground walking.

Investigation of Biomechanical Differences in Level Walking between Patients with Bilateral and Unilateral Total Knee Replacements.

Due to the high risk of a bilateral total knee arthroplasty (TKR) following unilateral TKR, this study was performed to investigate bilateral TKR patients. Specifically, we examined biomechanical differences between the first replaced and second replaced limbs of bilateral patients. Furthermore, we examined bilateral TKR effects on hip, knee, and ankle biomechanics, compared to the replaced and non-replaced limbs of unilateral patients.

The effects of heading motion and sex on lower extremity biomechanics in soccer players.

Background: Soccer is one of the most popular sports worldwide, which subsequently increases the number of injuries experienced by players. Furthermore, a large percentage of all anterior cruciate ligament injuries occur while playing soccer. In order to more clearly understand injury mechanisms, it is important to make the testing environment as real-life as possible.

Validity, reliability, and bias between instrumented pedals and loadsol insoles during stationary cycling.

The purpose of this study was to evaluate the validity and reliability of the loadsol in measuring pedal reaction force (PRF) during stationary cycling as well as lower limb symmetry. Ten healthy participants performed bouts of cycling at 1kg, 2kg, and 3kg workloads (conditions) on a cycle ergometer. The ergometer was fitted with instrumented pedals and participants wore loadsol plantar pressure insoles.

Effects of different slopes on hip and ankle biomechanics of replaced and non-replaced limbs of patients with total knee arthroplasty during incline ramp walking.

Although knee biomechanics has been examined, hip and ankle biomechanics in incline ramp walking has not been explored for patients with total knee arthroplasty (TKA). The purpose of this study was to investigate the hip and ankle joint kinematic and kinetic biomechanics of different incline slopes for replaced limbs and non-replaced limbs in individuals with TKA compared to healthy controls. Twenty-five patients with TKR and ten healthy controls performed walking trials on four slope conditions of level (0°), 5°, 10° and 15° on a customized instrumented ramp system.

Do Interlimb Knee Joint Loading Asymmetries Persist throughout Stance during Uphill Walking Following Total Knee Arthroplasty?

The purpose of this study was to determine differences in total (TCF), medial compartment (MCF), and lateral compartment (LCF) tibiofemoral joint compressive forces and related muscle forces between replaced and non-replaced limbs during level and uphill walking at an incline of 10°. A musculoskeletal modeling and simulation approach using static optimization was used to determine the muscle forces and TCF, MCF, and LCF for 25 patients with primary TKA. A statistical parametric mapping repeated-measures ANOVA was conducted on knee compressive forces and muscle forces using statistical parametric mapping.

Tibiofemoral compressive force during downhill walking in patients with primary total knee arthroplasty: A statistical parametric mapping approach.

Background: Downhill walking is a necessary part of daily life and an effective activity in post-operative rehabilitation following total knee arthroplasty. The purpose of this study was to determine differences in the behavior of total, medial, and lateral tibiofemoral compressive forces as well as knee extensor and flexor muscle forces between different limbs of patients with total knee arthroplasty (replaced, non-replaced) during downhill and level walking.

Methods: Musculoskeletal modeling and simulation were implemented to determine muscle forces and tibiofemoral compressive forces in 25 patients with total knee arthroplasty.

Medial and Lateral Tibiofemoral Compressive Forces in Patients Following Unilateral Total Knee Arthroplasty During Stationary Cycling.

Patients following unilateral total knee arthroplasty (TKA) display interlimb differences in knee joint kinetics during gait and more recently, stationary cycling. The purpose of this study was to use musculoskeletal modeling to estimate total, medial, and lateral tibiofemoral compressive forces for patients following TKA during stationary cycling. Fifteen patients of unilateral TKA, from the same surgeon, participated in cycling at 2 workrates (80 and 100 W).

Altered biomechanics in bilateral total knee replacement patients during stair negotiation.

Background: Many total knee replacement (TKR) patients need to have a contralateral knee replacement. Biomechanical differences between first and second replaced limbs of bilateral TKR have not been examined during stair negotiation. Additionally, it is unknown whether hip and ankle biomechanics of bilateral patients are altered.

Can changes of workrate and seat position affect frontal and sagittal plane knee biomechanics in recumbent cycling?

Changes in the workrate and seat position have been linked to changes in internal knee extension moment. However, there is limited research on effects of those changes on knee kinetics in recumbent bike. The purpose of this study was to examine the effects of different seat positions and workrates on KAbM, knee extension moment and perceived effort during stationary recumbent cycling.

Principal Component Analysis of Knee Joint Differences Between Bilateral and Unilateral Total Knee Replacement Patients During Level Walking.

Many unilateral total knee replacement (TKR) patients will need a contralateral TKR. Differences in knee joint biomechanics between bilateral patients and unilateral patients are not well established. The purpose of this study was to examine knee joint differences in level walking between bilateral and unilateral patients, and asymptomatic controls, using principal component analysis.

Overground Walking Biomechanics of Dissatisfied Persons With Total Knee Replacements.

Patient dissatisfaction following total knee replacement (TKR) procedures is likely influenced by both subjective and objective aspects. Increased pain and reduced performance on clinical tests have been shown in persons who are dissatisfied with the outcome of their surgery. However, it is unknown how overground walking kinematics and kinetics might differ in the dissatisfied versus satisfied patients following TKR surgery.

Are Medial and Lateral Tibiofemoral Compressive Forces Different in Uphill Compared to Level Walking for Patients Following Total Knee Arthroplasty?

The purpose of this study was to determine how tibiofemoral joint compressive forces and knee joint-spanning muscle forces during uphill walking change compared to level walking in patients with total knee arthroplasty (TKA). A musculoskeletal model capable of resolving total (TCF), medial (MCF), and lateral (LCF) tibiofemoral compressive forces was used to determine compressive forces and muscle forces during level and uphill walking on a 10 deg incline for twenty-five post-TKA patients. A 2 × 2 (slope: level and 10 deg × limb: replaced and nonreplaced) repeated measures analysis of variance was used to detect differences in knee contact forces between slope and limb conditions and their interaction.

Does saddle height influence knee frontal-plane biomechanics during stationary cycling?

Introduction: Cycling is a common modality for rehabilitation and exercise. However, there is a lack of information in the literature on the effects of saddle height adjustments on internal peak knee abduction moment, which is an important loading variable for the medial compartment of tibiofemoral joint for patients with knee osteoarthritis. The purpose of this study was to examine effects of saddle height on frontal-plane biomechanics of the knee during cycling.

Increased Q-factor increases medial compartment knee joint contact force during cycling.

As Q-Factor (QF: inter-pedal distance) is increased, the internal knee abduction moment (KAbM) also increases, however it is unknown if this increased KAbM is associated with increased medial compartment knee joint contact force in cycling. In the absence of in vivo measurement, musculoskeletal modeling simulations may provide a viable option for estimating knee joint contact forces in cycling. The primary purpose of this study was to investigate the effect of increasing QF on knee joint total (TCF), and medial (MCF) compartment contact force during ergometer cycling.

Knee biomechanics of patients with total knee replacement during downhill walking on different slopes.

Purpose: The purpose of this study was to compare knee biomechanics of the replaced limb to the non-replaced limb of total knee replacement (TKR) patients and healthy controls during walking on level ground and on decline surfaces of 5°, 10°, and 15°.

Methods: Twenty-five TKR patients and 10 healthy controls performed 5 walking trials on different decline slopes on a force platform and an instrumented ramp system. Two analyses of variance, 2 × 2 (limb × group) and 2 × 4 (limb × decline slope), were used to examine selected biomechanics variables.

Knee joint biomechanics of patients with unilateral total knee arthroplasty during stationary cycling.

Stationary cycling is typically recommended following total knee arthroplasty (TKA) operations. However, knee joint biomechanics during cycling remains mostly unknown for TKA patients. Biomechanical differences between the replaced and non-replaced limb may inform applications of cycling in TKA rehabilitation.

Effects of Increased Step-Width on Knee Biomechanics During Inclined and Declined Walking.

The purpose of this study was to investigate effects of preferred step width and increased step width modification on knee biomechanics of obese and healthy-weight participants during incline and decline walking. Seven healthy-weight participants and 6 participants who are obese (body mass index ≥ 30) performed 5 walking trials on level ground and a 10° inclined and declined instrumented ramp system at both preferred and wide step-widths. A 2 × 2 (step-width × group) mixed-model analysis of variance was used to examine selected variables.

A Finite Element Model for Estimation of Contact Dynamics During a Jumping Movement on a Trampoline.

In order to fully understand contact dynamics on a trampoline, a simulation approach using a musculoskeletal model coupled with a dynamic model of the trampoline is essential. The purpose of the study was to examine dynamics and selected lower extremity muscle forces in a landing and jumping movement on a trampoline, using a combination of finite element modeling and musculoskeletal modeling. The rigid frame of the trampoline was modeled in ADAMS and coupled with a finite element model of the elastic trampoline net surface in ANSYS.

Increased Q-Factor increases frontal-plane knee joint loading in stationary cycling.

Background: Q-Factor (QF), or the inter-pedal width, in cycling is similar to step-width in gait. Although increased step-width has been shown to reduce peak knee abduction moment (KAbM), no studies have examined the biomechanical effects of increased QF in cycling at different workrates in healthy participants.

Methods: A total of 16 healthy participants (8 males, 8 females, age: 22.

Effects of synthetic turf and shock pad on impact attenuation related biomechanics during drop landing.

Adding a shock pad as an underlayment to synthetic turf aims to improve attenuation of impact forces. The purpose of this research was to investigate effects of an infilled synthetic turf with three different shock pads on impact attenuation related biomechanics of lower extremity during the drop landing. Twelve active and healthy recreational male athletes performed 60 cm drop landing with a controlled landing technique on five surface conditions: a baseline surface (force platform), an infilled synthetic turf surface, turf plus foam shock pad, turf plus a low-density shock pad, and turf plus a high-density shock pad.

Lower-limb joint reaction forces and moments during modified cycling in healthy controls and individuals with knee osteoarthritis.

Background: Osteoarthritis (OA) is a clinical problem affecting an estimated 27 million adults in the United States, with the only clear treatment options being pain management. Cycling is an integral component of exercise for individuals with knee osteoarthritis, while the joint reaction forces during cycling remain unknown.

Methods: Thirteen subjects with medial compartment knee osteoarthritis and eleven healthy subjects performed a cycling protocol with a neutral pedal and four pedal modifications.