Joints are basically damaged by problems like arthritis and other diseases, injuries or other causes. Arthritis, old age or simply years of use may cause the joints to wear. Bones require need blood to be healthy, to grow and repair themselves, lack of which results in swelling, stiffness and pain in the joints.

A new joint, alternatively called a prosthesis, is either made of plastic or metal or both. A prosthesis may be cemented into place or not cemented, as per requirement. This is done with the view that the bone grows into it. Sometimes, both the methods may be combined and used to keep the new joint in place.

This kind of surgery is fast being accepted and thereby improving the lives of many. Sauch is its effectiveness that more than 1 million Americans have a hip or knee replaced each year. Research have proven that a joint replacement surgery helps you move around, especially during old age.
As far as risks are concerned, any and every surgery carries risks. The risks involved in a joint surgery is determined by factors like patient's health before surgery, how severe the arthritis is and the type of surgery that will be performed. It is advised to consult your doctor regarding this matter. A doctor specializing in joints will probably guide before, during and after surgery, so as to ensure you heal quickly and recover successfully.

Only a doctor can advise well on the urgency of getting a joint replaced. The doctor may perform an x-ray on your joints along with putting a small, lighted tube (arthroscope) into the joint to look for damage. A small sample of the tissue could also be tested.
After examining your joints, the doctor may suggest appropriate exercises, walking aids such as braces or canes, physical therapy, medicines and vitamin supplements. Medicines for arthritis comprise those drugs that minimise inflammation.
In the unfortunate case that the afore-mentioned treatments do not prove effective, the doctor may suggest an operation called an osteotomy. In this treatment, the surgeon aligns the joint by cutting the bone or bones around the joint, with the aim to improve alignment. This surgery is simpler than replacing a joint, however, it takes longer to recover. Joint replacement surgery is the best solutions for you if you suffer from constant pain and can’t move your joint's well.

First, the surgical team will provide you medicine for anesthesia. The anaesthesia medicine will block pain only in one part of the body or it may also your whole body to sleep, as preferred by you and implemented by the surgeon. The team will then replace the damaged joint with a prosthesis.
The duration of the surgery depends on the plight of the joints and the way the surgery is done. It takes about 2 hours or less to replace a knee or a hip, unless there are complicating factors.

A knee or hip surgery requires you to stay in the hospital for a few days. If you belong to the group of senior citizens or have additional disabilities, in that case you may need to spend several weeks in an intermediate-care facility before heading home. After the hip or knee replacement surgery, you may be advised to stand often or begin walking the day of surgery. At first, you will be provided with a walker or crutches to help you walk. You may experience light pain on a temporary basis in the new joint because your muscles are weak from not being used. The pain can be minimised with the help of medicines and should subside in a few weeks or months. Physical therapy begins the day after surgery and helps strengthen the muscles around the new joint. It also helps you regain motion in the joint. In case of shoulder replacement surgery, you can begin exercising the same day of the surgery. A physical therapist will guide you with range-of-motion exercises.

The success of a joint replacement surgery is determined by your activities after the surgery. If you follow your doctor's advise you are bound to bounce back to good shape. Consult your doctor thoroughly on the do's & dont's, like what to eat, medicines to take, and how to exercise and inform him if you feel any pain or trouble moving.
Joint replacement usually proves successful in most cases. In case problems occur, you need not worry as these are minor and treatable. Possible problems include:

Infection
Blood clots
Dislocation
Wear
Loosening
Nerve and blood vessel injury