74 year old male, in general good health. Recently diagnosed, approx 5 months ago, with Type II diabetes but has probably had it for a long time. Recent onset of leg weakness, legs just give out at the hips, leading to falls. Significant muscle atrophy of quads and hamstrings as well as hip flexor. More atrophy in thighs than calves. Also has moderate neuropathy in thighs. Normal CT scan of hips. What are differential diagnosis? Possible ALS? Myasthenia Gravis? MS?