Publications by authors named "Madeline Singer"

Introduction/aims: Efgartigimod is a neonatal Fc receptor blocker and was the first approved medication in its class for the treatment of generalized myasthenia gravis (gMG). As a novel therapy, little is known about the use of efgartigimod in clinical practice. This study aims to describe how efgartigimod is being incorporated into the current therapeutic landscape of MG.

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A 58-year-old man with recently diagnosed coccidioidal meningitis presented to the ED with a five-day history of headache, photopsia, blurred vision, and worsening encephalopathy. His coccidioidal meningitis had responded well to fluconazole therapy, but three weeks later, he developed acute symptomatic worsening. Unfortunately, his clinical worsening coincided with Arizona's worst seasonal West Nile Virus (WNV) outbreak.

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Background: An ankle-foot orthosis (AFO) is used to assist gait of people with chronic stroke. It is widely accepted that AFO's plantarflexion resistance affects sagittal knee moments during their gait. However, its effect on the coronal knee moment remains unclear.

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Plantarflexion resistance of an ankle-foot orthosis (AFO) plays an important role to prevent foot-drop, but its impact on push-off has not been well investigated in individuals post-stroke. The aim of this study was to investigate the effect of plantarflexion resistance of an articulated AFO on ankle and knee joint power of the limb wearing the AFO in individuals post-stroke. Gait analysis was performed on 10 individuals with chronic stroke using a Vicon 3-dimensional motion capture system and a Bertec split-belt instrumented treadmill.

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Background: Ankle-foot orthosis moment resisting plantarflexion has systematic effects on ankle and knee joint motion in individuals post-stroke. However, it is not known how much ankle-foot orthosis moment is generated to regulate their motion. The aim of this study was to quantify the contribution of an articulated ankle-foot orthosis moment to regulate ankle and knee joint motion during gait in individuals post-stroke.

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Background: Genu recurvatum (knee hyperextension) is a common issue for individuals post-stroke. Ankle-foot orthoses are used to improve genu recurvatum, but evidence is limited concerning their effectiveness. Therefore, the aim of this study was to investigate the effect of changing the plantarflexion resistance of an articulated ankle-foot orthosis on genu recurvatum in patients post-stroke.

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The plantarflexion resistive moments of an articulated ankle-foot orthosis play an important role in improving gait in individuals post stroke. However, the evidence regarding their magnitude required from the articulated ankle-foot orthosis to improve walking is still limited. Therefore, the primary aim of this study was to directly measure the plantarflexion resistive moments and the joint angular positions while walking using a prototype instrumented articulated ankle-foot orthosis in five individuals post stroke.

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Background: The adjustment of plantarflexion resistive moment of an articulated ankle-foot orthosis is considered important in patients post stroke, but the evidence is still limited. Therefore, the aim of this study was to investigate the effect of changing the plantarflexion resistive moment of an articulated ankle-foot orthosis on ankle and knee joint angles and moments in patients post stroke.

Methods: Gait analysis was performed on 10 subjects post stroke under four different plantarflexion resistive moment conditions using a newly designed articulated ankle-foot orthosis.

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The relationship between altered tibiotalar and subtalar kinematics and development of ankle osteoarthritis is unknown, as skin marker motion analysis cannot measure articulations of each joint independently. Here, we quantified the accuracy and demonstrated the feasibility of high-speed dual fluoroscopy (DF) to measure and visualize the three-dimensional articulation (i.e.

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Background: Stiffness of an ankle-foot orthosis plays an important role in improving gait in patients with a history of stroke. To address this, the aim of this case series study was to determine the effect of increasing plantarflexion stiffness of an ankle-foot orthosis on the sagittal ankle and knee joint angle and moment during the first and second rockers of gait.

Methods: Gait data were collected in 5 subjects with stroke at a self-selected walking speed under two plantarflexion stiffness conditions (0.

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Decreased reactive postural responses in elderly adults may place them at increased risk for falls and related injuries. The first step in addressing the high rate of falls in the elderly population is to determine a baseline for postural response in healthy young and healthy elderly individuals. To determine these age-related differences in reactive postural responses during recovery from posterior and anterior perturbations, we used the tether-release method in conjunction with a motion analysis system to evaluate overall movement latencies, overall movement amplitude and velocity, and joint-specific amplitude and velocity in healthy young (n = 10, mean age=25 ± 5) and healthy elderly participants (n = 10, mean age = 67 ± 6).

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Postural instability appears to be a dopamine resistance motor deficit in persons with Parkinson disease (PD); however, little is known about the effects of dopamine replacement on the relative biomechanical contributions of individual lower extremity joints during postural control tasks. To gain insight, we examined persons with PD using both clinical and laboratory measures. For a clinical measure of motor severity we utilized the Unified Parkinson Disease Rating Scale motor subsection during both OFF and ON medication conditions.

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