Osteoarthritis of the knee occurs when the cartilage coverings on the end of the femur and the top of the tibia wear out. The tibia has two special cartilage pads called menisci (one is called a meniscus). This cartilage becomes flattened, bone spurs form, the joint becomes inflamed, range of motion is lost, there is ensuing weakness, pain and difficulty with walking, climbing stairs, and getting in/out of chairs. Physical therapy can help with recovery of range of motion, strength, walking skills, and pain management. Aquatic therapy (often involving a customized exercise program) can be helpful.
After total knee replacement (also called a total knee arthroplasty), physical therapy helps with recovery of range of motion, pain management, strength, balance and walking skills, and endurance. Commonly, patients say, "Why did I have this surgery? I am worse off now." You must be patient. Give yourself at least 3 months to recover.
For more info, see osteoarthritis.