Hello, 
I have studied your case. 
According to your symptoms and findings there is 
osteoarthritis of your knee.
Due to varus  of knee or inward turning of leg there can be pressure on lateral aspect of foot.
. Continue medication prescribed to you.
You can start 
cartilage protecting medication like chondritin sulphate, that you need to take for couple of months.
Physiotherapy like 
ultrasound and tens will help, along with knee exercises.
Leg 
Muscle cramps are very common.
Take plenty of water, fluid intake will dilute toxins.
Physiotherapy with ultrasound and Tens will help you,
Yes you can do exercises like swimming, riding stationary bicycle, but do not overexert yourself.
Take potassium rich diet.
Hot and cold fomentation to leg. 
You need to continue you medication for couple of month to see effects.
Add tab methylcobal 1500 once day.
Hope this answers your query. If you have additional questions or follow up queries then please do not hesitate in writing to us. I will be happy to answer your queries.
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Wishing you good health.
Take care.