Thanks for writing to us
I suggest you to try quadriceps strengthening exercises which can be taught by your Orthopedician or Physiotherapist. This will help to relieve the possible muscle spasm which causes the pain.
Avoid weight bearing exercises. Do only mild aerobics
which does not put your knee to strain.
Eat a diet rich in fresh fruits and green leafy vegetables, nuts, milk, eggs, pulses and cereals. Do brisk walking exercise for 40 minutes daily. I would suggest you to try swimming as this will help you a lot.
I do hope that you have found something helpful and I will be glad to answer any further query.