What are the best exercises to rehab a severely strained knee joint?

Low impact. Generally, it is a good idea to keep the knee moving with as little impact as possible. Provided it is just a strain, and there are no fractures, torn meniscus or ligaments, a low impact exercise program including riding a stationary bike or elliptical machine would be advisable. If it hurts, don't do it and make sure you check with a physician.
Severe strain. I assume you mean quad and hams. Make sure there is not a near-complete tear. Slowly progress with gentle rom, modalities, pt, sort arc. Avoid lunges, deep knee bends, squats, jumping, and plyometrics til given the green light by your orthopedic or sports doc.

Related Questions

Suffered a crushed knee joint from accident. Too young for replacement. What's the best option for treatment? I'm not overweight and exercise daily.

Need more info. Sorry to hear about your knee. "crushed " doesn't sound good but i need more information to give u an answer. It would be best to look @ your x-rays and arthroscopic photos( if u have had your knee 'scoped') @ a minimum to give you your tx. Alternatives.Best of luck! Read more...

What is the best procedure to do for worn out cartilage in knee joint?

Cartilage. Options depend on amount of surface area involved--if small, possible microfracture, oats procedure for cartilage transfer, or chondrocyte transplant--the last of which may not be covered by insurance. Sometimes a simple scope debridement may get you some mileage. Read more...
Cartilage. If the "worn out cartilage" is referring to the meniscus then a meniscal transplant can be performed if there is significant meniscal loss and the patient is relatively young with no or minimal associated articular cartilage wear. If the 'worn out cartilage" is referring to the coating or articular cartilage of the femur then an articular cartilage can be considered with possible autologous tx. Read more...