Brief Answer:
knee replacement is needed.

Detailed Answer:
Hello,
Thanks for posting your query.
I have seen the images attached. Your father has severe arthritis and reduced joint space in the knee. These are basically age related degenerative changes in the weight bearing joints like knee and is characterized by joint pain and stiffness.
For osteoarthritis, weight reduction is the main treatment along with medicines to decrease pain like NSAID's - paracetamol, aceclofenac etc., Life style modifications like avoiding sitting cross legged, squatting, using XXXXXXX type toilets will decrease the rate of progression of osteoarthritis. Exercises like quadriceps strengthening, swimming, straight leg raising will help in improving the muscle strength around the knee and will help in decreasing pain.
In advanced stages knee replacement is the only option if the pain is persistent. The surgery is common and safe and should be done under the guidance of an expert surgeon. The complications depend on the physical condition of the patient and include infection scar formation prosthesis loosening etc.
I hope this answers your query.
In case you have additional questions or doubts, you can forward them to me, and I shall be glad to help you out.
Wishing you good health.
Regards.
Dr. Praveen Tayal.
For future query, you can directly approach me through my profile URL http://bit.ly/Dr-Praveen-Tayal

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