According to your father's age more difficulty in winter season take precautions for winter season.
Pain oil message and hot fermentation is good for him.You can call physiotherapist for some exercises, ultrasonic and IFT.It will help him.
Without consulting with proper history I don't advice any medicine atleast in this age.
Next Steps
consult a ayurvedic doctor with proper history and physical examination is better in his age.
Health Tips
Avoid urad dal,curd ,rice n excessive oily,salty , starched food.
diet should be take as per Ayurveda.