I am sorry to hear that your mother is having such troubles.
The fact that she was fine with walking prior to surgery and now has trouble suggests that something changed related to the surgery.
I think of several possibilities:
there could be a nerve injury
there could be something going on that is pushing on her nerves such a a collection of blood ( a postop hematoma) or an abscess
she developed a slipped disc from positioning on the operating table (did she have an epidural for anesthesia?)
I would suggest the following to help sort this out:
-get the operative note and understand what exactly was done at surgery ( you could also print in the report here and I can translate for you)
-get a CT scan of abdomen to look for hematoma, abscess, or tumor
-get her very well medicated to allow her to lie down for an MRI of her spine
in general neuropathies from surgery resolve.
here is a nice article on the topic
Pelvic nerve injury following gynecologic surgery: a prospective cohort study.
Am J Obstet Gynecol. 2009 Sep 15. [Epub ahead of print
Bohrer JC, Walters MD, Park A, Polston D, Barber MD.
OB/GYN & Women's Health Institute, Cleveland, OH.
OBJECTIVE: The purpose of this study was to determine the incidence and time course of postoperative neuropathy resulting from gynecologic surgery. STUDY DESIGN: A single cohort of 616 female patients undergoing elective gynecologic surgery for benign or malignant conditions at a tertiary care academic medical center underwent a postoperative neurologic evaluation to identify postoperative neuropathy of the lower extremities. RESULTS: Fourteen peripheral nerve injuries were observed in 11 patients, making the overall incidence of postoperative neuropathy 1.8% (95% confidence interval, 1.0-3.2). Injury to the lateral femoral cutaneous (5), femoral (5), common fibular (1), ilioinguinal/iliohypogastric (1), saphenous (1), and genitofemoral (1) nerves were detected. Complete resolution of neuropathic symptoms occurred in all but 1 patient (91%). Median time to resolution of symptoms was 31.5 days (range, 1 day to 6 months). CONCLUSION: The incidence of lower extremity neuropathy attributable to gynecologic operations is low, and these neuropathies resolve in the great majority of cases.