Full gait cycle analysis of lower limb and trunk kinematics and muscle activations during walking in participants with and without ankle instability

This document is the Accepted Manuscript version of the following article: Lynsey Northeast, Charlotte N. Gautrey, Lindsay Bottoms, Gerwyn Hughes, Andrew C. S. Mitchell, and Andrew Greenhalgh, ‘Full gait cycle analysis of lower limb and trunk kinematics and muscle activations during walking in participants with and without ankle instability’, Gait & Posture, Vol. 64: 114-118, July 2018. Under embargo until 7 June 2019. The final, definitive version is available online at doi: https://doi.org/10.1016/j.gaitpost.2018.06.001Background Chronic ankle instability (CAI) has previously been linked to altered lower limb kinematics and muscle activation characteristics during walking, though little research has been performed analysing the full time-series across the stance and swing phases of gait. Research Question The aim of this study was to compare trunk and lower limb kinematics and muscle activity between those with chronic ankle instability and healthy controls. Methods Kinematics and muscle activity were measured in 18 (14 males, 4 females) healthy controls (age 22.4 ± 3.6 years, height 177.8 ± 7.6 cm, mass 70.4 ± 11.9 kg, UK shoe size 8.4 ± 1.6), and 18 (13 males, 5 females) participants with chronic ankle instability (age 22.0 ± 2.7 years, height 176.8 ± 7.9 cm, mass 74.1 ± 9.6 kg, UK shoe size 8.1 ± 1.9) during barefoot walking trials, using a combined Helen Hayes and Oxford foot model. Surface electromyography (sEMG) was recorded for the tibialis anterior and gluteus medius. Full curve statistical parametric mapping was performed using independent and paired-samples T-tests. Results No significant differences were observed in kinematic or sEMG variables between or within groups for the duration of the swing phase of gait. A significantly increased forefoot-tibia inversion was seen in the CAI affected limb when compared to the CAI unaffected limb at 4–16% stance (p = 0.039). No other significant differences were observed. Significance There appears to be no differences in muscle activation and movement between CAI and healthy control groups. However, participants with CAI exhibited increased inversion patterns during the stance phase of gait in their affected limb compared to their unaffected limb. This may predispose those with CAI to episodes of giving way and further ankle sprains.Peer reviewedFinal Accepted Versio

Surface Electromyography Applied to Gait Analysis: How to Improve Its Impact in Clinics?

Surface electromyography (sEMG) is the main non-invasive tool used to record the electrical activity of muscles during dynamic tasks. In clinical gait analysis, a number of techniques have been developed to obtain and interpret the muscle activation patterns of patients showing altered locomotion. However, the body of knowledge described in these studies is very seldom translated into routine clinical practice. The aim of this work is to analyze critically the key factors limiting the extensive use of these powerful techniques among clinicians. A thorough understanding of these limiting factors will provide an important opportunity to overcome limitations through specific actions, and advance toward an evidence-based approach to rehabilitation based on objective findings and measurements

Comparing Lower-Limb Muscle Activity During Gait Performed in Water Versus on Land

The purpose of this study was to compare lower-limb muscle activation during gait, performed in water versus on land, in order to provide preliminary evidence for the benefit of aquatic treadmill walking in treating individuals with foot drop. Foot drop is a debilitating symptom of several neurological disorders characterized by the inability to dorsiflex the foot while walking. Generally, it is due to weakness in the ankle dorsiflexor muscles and/or increased tone in the plantar flexor muscles. Previous research has found that exercise interventions that demand greater than normal activation of the tibialis anterior (TA) (i.e., the primary ankle dorsiflexor) may improve walking performance in individuals with foot drop. Correspondingly, higher drag forces associated with walking in water may also facilitate increased activation of the TA during the swing phase of gait, potentially leading to similar improvements in gait. Thus, the current study compared surface electromyographic activity in the TA and medial gastrocnemius (GM) during gait performed in water versus on land. Thirty-eight healthy, recreationally active adults completed the study. Each participant walked under five conditions (Land 2.5 mph, Land 3.5 mph, Water 2.5 mph, Water 3.5 mph, and Water 3.5 mph + Jets) for 2-min each while muscle activity in the TA and GM were recorded using surface electromyography. A two-way within-subjects analysis of variance was used to evaluate main effects and interactions. As a secondary analysis, paired samples t-tests were used to assess differences between walking in water with and without jet resistance. TA activity during the swing phase of gait was greater in water than on land and this effect increased with greater walking velocity and the application of jet resistance. Furthermore, GM activity during the stance phase of gait was lower in water compared to land. The results of this study provide evidence in support of aquatic treadmill walking as a potential treatment for individuals with foot drop. Additional research is needed to establish if a causal relationship exists between increased TA activity during exercise and improvements in voluntary dorsiflexion during gait in individuals with foot drop

Comparison of gluteus medius muscle activity in Haflinger and Noriker horses with polysaccharide storage myopathy

Type 1 polysaccharide storage myopathy caused by genetic mutation in the glycogen synthase 1 gene is present in many breeds including the Noriker and Haflinger horses. In humans, EMG has already been used to document changes in the muscle activity patterns of patients affected by human glycogen storage disorders. Therefore, the aim of the present study was to describe gluteus muscle activity with surface electromyography (sEMG) in Haflinger and Noriker horses with known GYS1 mutation status during walk and trot. Thirty‐two horses (11 Haflinger and 21 Noriker horses) with homozygous non‐affected (GG), heterozygous affected (GA) and homozygous affected (AA) status of GYS1 mutation without overt clinical signs of any myopathy were selected for the current study. Using surface electromyography gluteus medius muscle activity at walk and at trot was measured, and muscle activity was described in relation to the maximum observed value at the same sensor and the same gait. In order to further describe the signals in detail comprising both frequencies and amplitudes, the crossings through the baseline and the 25, 50 and 75 percentile lines were determined. The result of the relative muscle activity did not show a consistent difference between affected and non‐affected horses. Genetically affected (GA and AA) horses showed significantly less density of muscle activity for both gaits and horse breeds except for the crossings per second at the baseline and 75 percentile at walk in the Haflinger horses and 75 percentile at trot in the Noriker horses. The medians of all calculated density values were significantly lower in the GA Haflingers compared to the GG Haflingers (p = 0.012) and also in the AA Norikers compared to the GG Norikers (p = 0.011). Results indicate that the GYS1 mutation reduces the number of functional muscle fibres detected by sEMG measurements even in the absence of overt clinical signs

Variability in surface electromyogram during gait analysis of low back pain patients

This paper describes the analysis of the variance of the amplitude of surface electromyogram (SEMG) recorded from the L4/ L5 region of the erector spinae for healthy participants and people suffering with low back pain (LBP) when they were walking and running on a treadmill. The results indicate that there was no significant difference in the variance and in the change of variance over time of the exercise between the two groups when the participants were walking. However, when the participants were running, there was a significant difference between the two cohorts. While there was an increase in the variance over the duration of the exercise for both of the groups, the increase in variance of the LBP group was much greater (order of ten times) compared with that of the healthy participants. The difference between the two groups was also very significant when observing the change of variance over time. From these results, it is suggested that variance of SEMG of the muscles of the lower back, recorded when the participants are running, can be used to identify LBP patients

Lower Limb Muscle Activation in Young Adults Walking in Water and on Land

Previous research has shown that exercise interventions requiring increased activation of the tibialis anterior (TA), the primary ankle dorsiflexor, can improve walking performance in individuals with foot drop. Correspondingly, heightened drag forces experienced during walking performed in water may augment TA activation during the swing phase of gait, potentially leading to improved walking gait on land. Therefore, this study aimed to compare surface electromyographic (sEMG) activation in the TA and medial gastrocnemius (GM) during gait performed in water versus on land. Thirty-eight healthy, recreationally active young adults, comprising 18 females and 20 males, participated in the study. Each participant completed 2 min walking trials under five conditions: land 2.5 mph, land 3.5 mph, water 2.5 mph, water 3.5 mph, and water 3.5 mph with added jet resistance. Stride kinematics were collected using 2-dimensional underwater motion capture. TA and GM, muscle activation magnitudes, were quantified using sEMG root-mean-square (RMS) amplitudes for both the swing and stance phases of walking. Additionally, TA and GM co-activation (Co-A) indices were estimated. Two-way within-subjects repeated measures analyses of variance were used to evaluate the main effects of and interactions between the environment and walking speed. Additionally, paired sample t-tests were conducted as a secondary analysis to investigate differences between walking in water at 3.5 mph with and without added jet resistance. Main effects and interactions were observed across various stride kinematics and sEMG measures. Notably, TA sEMG RMS during the swing phase of walking gait performed at 2.5 mph was 15% greater in water than on land (p \u3c 0.001). This effect increased when walking gait was performed at 3.5 mph (94%; p \u3c 0.001) and when jet resistance was added to the 3.5 mph condition (52%; p \u3c 0.001). Furthermore, TA Co-A was increased during the stance phase of gait in water compared to on land (p \u3c 0.001), while GM Co-A was reduced during the swing phase (p \u3c 0.001). The findings of this study offer compelling evidence supporting the efficacy of aquatic treadmill walking as a potential treatment for individuals suffering from foot drop. However, further research is needed to evaluate whether a causal relationship exists between heightened TA activation observed during aquatic treadmill walking and improvements in voluntary dorsiflexion during gait

Application of surface EMG in diabetic disease

Summary: English The World Health Organization warns that, in 2000, as many as 33 million Europeans suffered from diabetes, approximately 15% will likely develop foot ulcers, and approximately 15% to 20% of these patients will face lower-extremity amputation. In 2004, an estimated 3.4 million people died from consequences of high blood sugar. Diabetic neuropathy is the most common chronic complication associated with diabetes mellitus, affecting 20–50% of diabetic patients 10 years after their diagnosis. Peripheral neuropathy and peripheral arterial disease are the most common and invalidating diabetes’s complications, involved in the pathogenesis of diabetic foot. They account for the leading cause of non-traumatic lower limb amputations. It results from two factors. The first one is a reduced blow of blood in the inferior limbs, caused from the presence of obliterating peripheral arteriopathy disease. The second is the progressive laceration of nervous fibers (neuropathy) that cause a reduction of the sensitivity (also to the pain) and of the ability of movement, and that helps the appearance of lesions. Together with diabetes falls in older adults are a big public health concern and have provided much of the motivation for research into age-related changes in human gait. Tripping during walking is the predominant cause of falls not only in the elderly but also in the neuropathic subjects. Trips can occur during walking on a level ground, but also during crossing visible obstacle, stair ascending and descending. The social and economic weight of the diabetic foot and the tragic consequences that brings with it can be reduced through a prompt diagnosis and treatment from the very beginning. The aim of this thesis, was to evaluate differences in gait parameters, in performing stair ascending and descending task and evaluation of muscle fatigue during treadmill protocol in diabetes subjects with and without complications, in order to provide a further tool for early diagnosis which allows clinicians to change, if is necessary, or only to control, as soon as possible, the follow-up of patients according to their specific characteristics

Acute Effects of Multi-Joint Eccentric Exercise on Lower Extremity Muscle Activation Measured During Land and Water Walking

Although prior literature has established the preliminary clinical benefits of aquatic exercise across various clinical populations, there is a need to explore the potential for including aquatic-based movement as a key component of a multi-modal approach toward improving mobility and reducing fall risk. Eccentric exercise may complement aquatic exercise given that movements performed in water immersion tend to be low impact. Eccentric exercise may also improve the passive stiffness of lower extremity extensors, which gives an additional rationale for the potential of eccentric exercise to reduce fall risk when combined with aquatic exercise. There may also be an acute response to spinal reflex activity post-eccentric exercise, which could enhance the benefit of performing aquatic exercise if eccentric exercise is performed immediately prior. The purpose of this study was to compare lower-limb muscle activation during gait performed in water versus on land, before and after a short bout of eccentric exercise, in order to investigate the potential of a multi-modal approach toward improving gait abnormalities that relate to fall risk in older adults. Twenty-six healthy, recreationally active young adults completed the study. Each participant walked on land and in water, both prior to and after eccentric exercise for 2-min each while root-mean-square (RMS) muscle activity of the tibialis anterior (TA), medial gastrocnemius (GM), biceps femoris (BF), and vastus lateralis (VL) were recorded during the swing and stance phases of gait, using surface electromyography. A two-way within-subjects analysis of variance was used to evaluate for main effects and interactions. Main effects of environment were observed across all measures of muscle activation (F = 4.5 – 602.6, p \u3c0.001 – 0.036) except for BF RMS during the swing phase (F = 0.2, p = 0.699). Co-activation of the thigh during swing was the only measure to reveal an environment × eccentric exercise interaction (F = 5.4, p \u3c 0.001) and main effect of eccentric exercise (F = 7.4, 2 p = 0.008).The significant interaction on Co-activation of the thigh during swing appeared to be influenced by a non-significant reduction in VL RMS observed for post-eccentric exercise land walking. This suggests that participants may have adopted a different motor strategy, possibly anticipating the greater vertical ground reaction forces during foot impact in land walking compared to water walking, leading to reduced VL activation during swing. The results of this study provide evidence that additional research is warranted and may be aimed at exploring the potential of a multi-modal training approach involving aquatic treadmill walking and eccentric exercise to enhance mobility and address fall risk in clinical populations