Brief Answer:
intestine disturbances with possible nerve compression lower spine.

Detailed Answer:
Hello and welcome to Healthcaremagic.com
I have read your query and here is my advise.

* There sounds to be associated components from abdomen condition ( as digestive
disorder ) responsible for smelly gas and yellow stool as well as spinal condition ( as
nerve compression or else ) responsible for severe lower back pain radiating to thigh
with burning and numbness.

* As already home measures have been tried and amount of pain is significant, it is
recommended to get its thorough work up with your physician in terms of
- basic lab reports
- ultrasound of abdomen & pelvis
- x-ray lower lumbar spine region
- colonoscopy

* Till that time, following measures would help to relieve the issue for some time period
- local application of analgesic spray as camphor, diclofenac over lower back
- prescription of dicyclomine or tramadol hydrochloride with your general practitioner
( if there is no history of drug sensitivity )
- plenty of liquids and high fiber diet

Hope this information would be useful to you.
Wish you best recovery and fine health.

Regards.
Dr Bhagyesh

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