Thank you for posting your query.
There could be several reasons for the falls and weakness of legs in your father. These include:
1. New stroke, affecting the leg area of brain,
2. Disc prolapse
in the lumbar region, causing nerve compression of the leg nerves,
of knee and hips, leading to pain and weakness,
4. Osteoporosis- low bone density
leading to bone and muscle weakness
can examine your father and come to a conclusion regarding the cause of weakness and falls.
There is no need to worry, as proper medical treatment would lead to improvement.
Dr Sudhir Kumar MD DM (Neurology)
Senior Consultant Neurologist