Hip flexor muscle dysfunction during walking at self-selected and fast speed in patients with aortoiliac peripheral arterial disease

A biomechanical perspective on walking in patients with peripheral artery disease

The most common symptom of peripheral artery disease (PAD) is intermittent claudication, which consists of debilitating leg pain during walking. In clinical settings, the presence of PAD is often noninvasively evaluated using the ankle-brachial index and imaging of the arterial supply. Furthermore, various questionnaires and functional tests are commonly used to measure the severity and negative effect of PAD on quality of life. However, these evaluations only provide information on vascular insufficiency and severity of the disease, but not regarding the complex mechanisms underlying walking impairments in patients with PAD. Biomechanical analyses using motion capture and ground reaction force measurements can provide insight into the underlying mechanisms to walking impairments in PAD. This review analyzes the application of biomechanics tools to identify gait impairments and their clinical implications on rehabilitation of patients with PAD. A total of 18 published journal articles focused on gait biomechanics in patients with PAD were studied. This narriative review shows that the gait of patients with PAD is impaired from the first steps that a patient takes and deteriorates further after the onset of claudication leg pain. These results point toward impaired muscle function across the ankle, knee, and hip joints during walking. Gait analysis helps understand the mechanisms operating in PAD and could also facilitate earlier diagnosis, better treatment, and slower progression of PAD.

Muscle forces and power are significantly reduced during walking in patients with peripheral artery disease

Patients with peripheral artery disease (PAD) have significantly reduced lower extremity muscle strength compared with healthy individuals as measured during isolated, single plane joint motion by isometric and isokinetic strength dynamometers. Alterations to the force contribution of muscles during walking caused by PAD are not well understood. Therefore, this study used simulations with PAD biomechanics data to understand lower extremity muscle functions in patients with PAD during walking and to compare that with healthy older individuals. A total of 12 patients with PAD and 10 age-matched healthy older controls walked across a 10-meter pathway with reflective markers on their lower limbs. Marker coordinates and ground reaction forces were recorded and exported to OpenSim software to perform gait simulations. Walking velocity, joint angles, muscle force, muscle power, and metabolic rate were calculated and compared between patients with PAD and healthy older controls. Our results suggest that patients with PAD walked slower with less hip extension during propulsion. Significant force and power reductions were observed in knee extensors during weight acceptance and in plantar flexors and hip flexors during propulsion in patients with PAD. The estimated metabolic rate of walking during stance was not different between patients with PAD and controls. This study is the first to analyze lower limb muscular responses during walking in patients with PAD using the OpenSim simulation software. The simulation results of this study identified important information about alterations to muscle force and power during walking in those with PAD.

A Swine Hind Limb Ischemia Model Useful for Testing Peripheral Artery Disease Therapeutics

Currently, there is no large animal model of sustained limb ischemia suitable for testing novel angiogenic therapeutics for peripheral artery disease (PAD) such as drugs, genes, materials, or cells. We created a large animal model suitable for efficacy assessment of these therapies by testing 3 swine hind limb ischemia (HLI) variations and quantifying vascular perfusion, muscle histology, and limb function. Ligation of the ipsilateral external and bilateral internal iliac arteries produced sustained gait dysfunction compared to isolated external iliac or unilateral external and internal iliac artery ligations. Hyperemia-dependent muscle perfusion deficits, depressed limb blood pressure, arteriogenesis, muscle atrophy, and microscopic myopathy were quantifiable in ischemic limbs 6 weeks post-ligation. Porcine mesenchymal stromal cells (MSCs) engineered to express a reporter gene were visualized post-administration via positron emission tomography (PET) in vivo. These results establish a preclinical platform enabling better optimization of PAD therapies, including cellular therapeutics, increasing bench-to-bedside translational success. A preclinical platform for porcine studies of peripheral artery disease therapies including (1) a hind limb ischemia model and (2) non-invasive MSC viability and retention assessment via PET.

Relations between gait characteristics and subjective visual vertical results in young adults

OBJECTIVE

Subjective visual vertical (SVV) deviation can indicate impairments of motion perception and spatial orientation in individuals with vestibular disorders. This study investigated the influence of SVV on tandem gait ability by assessing differences between temporal, spatial, and kinematic characteristics in young adults.

METHODS

We recruited sixteen young adults with increased SVV and 17 age-matched control subjects. All subjects recruited for this study were with no history of neurological or musculoskeletal diseases. Knee and hip-joint kinematic data, spatio-temporal parameters, and gait variability were measured during tandem gait.

RESULTS

Stride time variability and stride velocity variability were significantly greater in the experimental group than the control group (p < 0.05). In addition, a significant correlation was observed between stride time variability and SVV results (r = 0.345, p < 0.05). However, hip and knee joint angles were non-significantly different in the experimental and control groups (p > 0.05) and spatio-temporal parameters were similar between the two groups (p > 0.05).

CONCLUSION

Stride time variability and stride velocity variability during tandem gait were significantly different in the experimental and control groups. We presume that increased SVV deviation is related to greater gait variability during tandem gait.

Physical activity and fitness in survivors of head and neck cancer

PURPOSE

The purposes of the study were (1) to assess the physical activity (PA) status, muscle strength (MS), and flexibility of survivors of head and neck cancer (HNC) and compare these findings with normative data from national labor fitness measures; (2) to examine the differences among PA subgroups, as categorized using Godin's scores; and (3) to examine the association between stretching exercises and cervical range of motion (CROM).

METHODS

A cross-sectional study with consecutive sampling was used to recruit HNC survivors from a medical center in Northern Taiwan who had completed either radiation therapy (RT) or multimodality treatments including RT within the current 5 years. The level of PA, daily function, fatigue, quality of life (QOL), MS (handgrip and hip flexor), BMI, and flexibility (CROM and fingertip-to-floor tests) of the participants were assessed.

RESULTS

A total of 108 participants completed the assessments from 135 eligible patients (80% response rate). Although 60.2% reported engaging in PA, only 16.7% met WHO guidelines. Compared to subjects in the normative data, the survivors of HNC in this study had poorer handgrip strength, BMI, and CROM, but better forward flexion. The participants who were consistent with WHO PA guidelines reported less fatigue, better right hip flexor MS, and better QOL than those who did not engage in any PA.

CONCLUSION

Lack of sufficient PA and generally poorer fitness were found in study subjects. Longitudinal research to explore changes in fitness and barriers to PA compliance is strongly suggested to better enhance HNC patients' PA and fitness.

Sarcopenia and peripheral arterial disease: a systematic review

BACKGROUND

Patients with lower extremity peripheral arterial disease (PAD) and sarcopenia are a population at risk requiring specific and targeted care. The aim of this review is to gather all relevant studies associating sarcopenia and PAD and to identify the underlying pathophysiological mechanisms as well as potential therapeutic strategies to improve skeletal muscle function.

METHODS

A systematic review was carried out following the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

RESULTS

Data extraction allowed the evaluation of 140 publications; 87 met the inclusion criteria; of which 79 were included in the final review, reporting sufficient data for epidemiological and diagnostic criteria, mechanical analysis, and therapeutic approaches. Epidemiological analysis and diagnostic criteria were based on 18 studies following 2362 PAD patients [31.39% (SD 7.61) women], aged 72.42 (SD 2.84); sarcopenia was present in 34.63% (SD 12.86) of the patients. Mechanical and pathway analysis were based on five animal studies and 29 clinical reports, showing significantly altered muscle strength and function in 1352 PAD patients [26.49% (SD 17.32) women], aged 67.67 (SD 5.14) years; impaired muscle histology in 192 PAD patients (9.2% (SD 11.22) women), aged 64.3 (SD 0.99) years; +58.63% (SD 25.48) of oxidative stress in 69 PAD patients [16.96% (SD 8.10) women], aged 63.17 (SD 1.43) years; mitochondriopathy in 153 PAD patients [29.39% (SD 28.27) women], aged 63.50 (SD 1.83) years; +15.58% (SD 7.41) of inflammation in 900 PAD patients [40.77% (SD 3.71) women], aged 74.88 (SD 2.76) years; and altered signalling pathways in 51 PAD patients [34.45% (SD 32.23) women], aged 72.25 (SD 5.25) years. Therapeutic approaches analysis was based on seven animal studies and 21 clinical reports. In total, 884 patients followed an exercise therapy, and 18 received an angiogenesis treatment; 30.84% (SD 17.74) were women. Mean ages of patients studied were 66.85 (SD 3.96).

CONCLUSIONS

Sarcopenia and lower extremity PAD have musculoskeletal consequences that directly impair patients' quality of life and prognosis. Although PAD is primarily a vascular disease, all etiological factors of sarcopenia identified so far are present in PAD. Indeed, both sarcopenia and PAD are accompanied by oxidative stress, skeletal muscle mitochondrial impairments, inflammation, inhibition of specific pathways regulating muscle synthesis or protection (i.e. IGF-1, RISK, and SAFE), and activation of molecules associated with muscle degradation. To date, besides revascularization, the best therapeutic strategy includes exercise, but approaches targeting the underlying mechanisms still deserve further studies.

The difference of gait characteristic according to the variety of dual tasks in young healthy adults

BACKGROUND

Walking in daily life is often accompanied by an attention-demanding task, which requires a different attentional load and external environments. Therefore, various gaits require complex and systematic interactions between several nervous systems, such as sensory association, cognitive functions, and the musculoskeletal system.

OBJECTIVE

Dual-task conditions during gait can affect the interaction between cognitive processing and motor behavior. This study investigated the effect of two types of cognitive dual tasks and one type of manual dual task (MDT) on kinematic and spatiotemporal parameters of gait in young healthy adults.

METHODS

We recruited 30 healthy young adults in this study. All participants performed normal gait, and two types of cognitive tasks (subtraction dual task, SDT; and working memory dual task, WMDT) and MDT (carrying a cup filled with water) during gait. This study assessed kinematic data during the stance and swing phases and spatiotemporal parameters.

RESULTS

MDT gait showed a significant decrement of hip-joint movement during the stance phase compared to the normal gait (p < 0.05). Stride velocity significantly decreased during SDT and WMDT gait compared with the normal gait (p < 0.05). MDT gait showed significant decrement of all spatiotemporal parameters of gait compared with normal gait (p < 0.05).

CONCLUSION

We reported that MDT gait can induce decreased hip-joint motion during the stance phase and reduced all spatiotemporal parameters to maintain balance and reduce the risk of falling. Therefore, motor dual tasks while walking would be useful as an intervention strategy to rehabilitate or train people at risk for falling.