Greetings from health care magic!!! I am Dr Thakker and shall be answering your question.
I very well understand your concerns about your mothers health and her inablility to walk. I shall try my best to give you a definitive plan of action for hier.Spinal stenosis
causes neurologic claudication, in which the patient feels pain on walking and it is relieved on bending forward. This occurs because bending forward enlarges the spinal canal and reduces the traction on nerves. your mom also has intermittent claudication
due to circulatory block. This leads to pain in the calf on walking which is relived with rest.
However, the following factors may contribute to her difficulty to walk upstairs and we need to rule them out:
1) Senile disuse atrophy of her leg muscles. this needs physiotherapy and conditioning exercises.
2) Muscle disease like Polymyositis/ Dermatomyositis
3) Diabetic amyotropy wherein patients have proximal muscle weakness
4) If she was exposed to steroids in the past, this could be from steroid myopathy
6) Arthritis of her hip or knee joints
I wish to know more details of your mother regarding her diabetic status, past medical history and history of medications. I would recommend that a neurologist
opinion would be very helpful along with blood tests like sugar test, t3, t4 , tsh for thyroid, xray pelvis with both hips. we can then go ahead after these results.
I hope this helps you out. If you have any more questions, please do not hesitate to write back to me.