What could cause asymmetric leg weakness?

Hello doctor,

My mother, who is 68 years old, has been complaining for the past year that her left leg moves more slowly than her right whenever she walks. Due to this, after walking for a distance, she must stop for a while, out of fear that she would fall. After stopping for a while, say for five to ten minutes, she can walk normally for a distance again without any problems. Also, in order to touch down her left leg on the ground while climbing steps, she must exert more force on her left leg. She cannot walk quickly like a normal person because her two legs are not moving at the same speed when she walks; in fact, her left leg is moving more slowly than her right. As a result, whenever she needs to walk somewhere, she avoids it because of this walking issue. Other than that, none of her legs hurt when she is standing or sitting. Only when walking does one leg move a little slower than the other, which I believe is a result of weakness or some form of numbness in that leg. She can do her daily household activities normally without any pain. Also, while walking for some distance she can walk like a normal person without any pain in the leg or anywhere, but after walking some distance she stops out of fear that she would fall as I described above. Also, at the foot dorsum, she got a slight muscle strain during that leg movement, however, there was no pain or swelling at any part of the leg or foot. Also, she completed a one-month vitamin D3 course (weekly once), one-month Supradyn and antioxidant, and one-month calcium+vitamin D3 course but with no improvement. Last seven months she was on AKT for LNTB, however, that course is also over now and she can do all the activities normally. Also, this leg issue was well before she was detected with LNTB and all her latest blood reports, ESR, and CRP are also normal. So what could be the possible reasons for her leg issue described above in detail and what is the possible remedy or treatment? Her BP medications include Telmipil CT, Nicardia retard 20, and Arkamin 100 mcg, and her latest BP is 150/90 mm of Hg. I need your insightful judgment. Thanks a lot.

Hello doctor,

Along with what I already said in my previous message, she also frequently complains of a slight backache, which typically goes away in three to four days after taking painkillers and muscle relaxants. But this pain comes back after a few days. It is not a serious discomfort but happens frequently. I am eagerly anticipating your thoughtful response and next move.