Hi..
Thanks for contacting practo for health query.
I am a senior physician Dr.Shanmugavadivu answering your question.
You said your father has problem in using leg ,but what kind of problem -pain or inability to use lower limb.
Kindly revert back to us with more information whether pain with restricted movements or inability to use with stiffness or flaccidity.
Next Steps
Kindly take your father to a physician may be he will guide you after clinical examination.
Health Tips
Till forth support your father on movements because if he fall,things might get complicated.
Take care.