Brief Answer:
Symptoms may be due to femoral artery occlusion.

Detailed Answer:
Hi

Thanks for posting your query on HCM.
I appreciate your concern for the increasing leg weakness.

The peripheral arterial disease (like occlusion of femoral artery due to atherosclerosis) is typically manifested as "Intermittent claudication" which refers to leg pain or cramping that occurs with exercise and subsides with rest after several minutes.
Other symptoms include numbness of the leg, weakness and atrophy (diminished size and strength) of the calf muscle, feet turn pale when they are elevated, and turn dusky red in dependent position.
Hair loss over the dorsum of the feet and thickening of the toenails
Painful ulcers and/or gangrene in the toes.
Specific sounds (called bruits) that can be heard over the affected artery with a stethoscope.

Other causes for the progressive leg weakness:

1. Sciatica which occurs due to compression of the nerves as they exit the spinal cord through the holes between the vertebrae of the backbone.

2. Motor neurone disease causes a progressive weakness of the muscles.
Symptoms may affect just one leg at first then gradually spread to involve other limbs.
3. Guillain-Barre Syndrome causes weakness or a tingling feeling in the legs which can spread to upper body.

In view of the possible causes for the progressive leg weakness, without no other specific symptoms/signs, I am unable to arrive at a definitive condition. Therefore it is best we plan necessary investigations. You are hereby advised to consult a doctor for proper evaluation and you may need the following investigations to arrive at a diagnosis like Doppler Ultrasound or Angiogram to rule out arterial obstruction and Electromyography or Nerve conduction studies for the neurological causes.

Hope these suggestions could be useful in detecting the cause for your present problem.

Wishing you best of your health.

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