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Lower Motor Neuron Signs

Muscle Wasting / Muscle Atrophy

One can appreciate from this photo that there is significant lower limb wasting (or muscle atrophy) of the right leg compared to the left. The right leg is also shorter compared to the left. Muscle wasting (or atrophy) is due to denervation of the muscle ...

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These two videos are from a middle-aged man presenting with progressive bilateral lower limb and right upper limb weakness for few months. In the first video, there are prominent fasciculations over the entire right upper limb. Whilst in the second video, fasciculations can also be ...

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The knee-jerk, ankle-jerk and plantar reflexes are being examined in this patient. There is a slight down-going plantar reflex on the right side. Otherwise, all other reflexes are absent. Discussion of the sign Areflexia may indicate deficits in the reflex loop. This may be due to ...

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Facial Nerve Palsy

In this video, one can appreciate that the patient has a lower motor neuron type of weakness affecting the right facial nerve. On asking the patient to look upwards (stimulation of the frontalis muscles), one can appreciate the lack of wrinkles over the forehead on ...

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