Thanks for your question.
I am Dr.AK and I would be glad to assist you with your concerns today.
This is most likely to be due to a condition known as lumbar canal stenosis where the nerves traveling through the lumbar spine get compressed because of the decreased diameter of the spinal canal.
The feeling of weakness in thighs is known as neurogenic claudication.
You need to have a MRI of lumbo sacral spine to confirm the pathology.
The disc bulge at l5 s1 can be contributing to lumbar canal stenosis.
Please reply if you need any clarification.
This is unlikely to be related to anxiety though the condition may be increasing your anxiety.
Other possible cause can be decreased blood supply to lower limbs but less likely as usually pain with decreased blood supply is felt in the legs and feet.
Thanks for replying.
Not being active would not cause weakness in thighs and neither would it cause burning sensation.These are likely to be nerve related symptoms.
Blood tests would be normal as this is not a metabolic or biochemical disorder.This is more like a mechanical disorder which causes the nerve s to get compressed.
If something else like electrolyte disturbance was responsible it would show on blood tests.
Spinal tumor is a rare diagnosis compared to lumbar canal stenosis and you have not described anything which would suggest one.
Get it treated properly and that should help bring down your anxiety.