My Mom Got Up From The Couch And Felt Something

My mom got up from the couch and felt something pull in her leg almost 3 weeks ago, she wasn't really in pain at first but now is unable to bare any weight on it. She was taking to ED where a pelvic scan, x ray, mri and blood work was done. She was sent on with muscle relaxers and tramadol. She initially could walk with a walker or cane but now can only crawl. More tests has been ordered but no PT or exercise at this point. What could be causing this and what she we do that isn't being done? if it were a ligament or muscle as suspected, it seems there would some improvement
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