What is a Hip Replacement?
Hip replacement, or arthroplasty, is a surgical procedure in which the diseased parts of the hip joint are removed and replaced with new, artificial parts. These artificial parts are called the prosthesis. The goals of hip replacement surgery include increasing mobility, improving the function of the hip joint, and relieving pain.

Who should have Hip Replacement surgery?
People with hip joint damage that causes pain and interferes with daily activities despite treatment may be candidates for hip replacement surgery. Osteoarthritis is the most common cause of this type of damage. However, other conditions, such as rheumatoid arthritis (a chronic inflammatory disease that causes joint pain, stiffness, and swelling), osteonecrosis (or avascular necrosis, which is the death of bone caused by insufficient blood supply), injury, and bone tumors also may lead to breakdown of the hip joint and the need for hip replacement surgery. In the past, doctors reserved hip replacement surgery primarily for people over 60 years of age. The thinking was that older people typically are less active and put less stress on the artificial hip than do younger people. In more recent years, however, doctors have found that hip replacement surgery can be very successful in younger people as well. New technology has improved the artificial parts, allowing them to withstand more stress and strain and last longer. Today, a person’s overall health and activity level are more important than age in predicting a hip replacement’s success. Hip replacement may be problematic for people with some health problems, regardless of their age. For example, people who have chronic disorders such as Parkinson’s disease, or conditions that result in severe muscle weakness, are more likely than people without chronic diseases to damage or dislocate an artificial hip. People who are at high risk for infections or in poor health are less likely to recover successfully. Therefore they may not be good candidates for this surgery. Recent studies also suggest that people who elect to have surgery before advanced joint deterioration occurs tend to recover more easily and have better outcomes.

Why do people have Hip Replacement surgery?
For the majority of people who have hip replacement surgery, the procedure results in:

What does Hip Replacement surgery involve?
The hip joint is located where the upper end of the femur, or thighbone, meets the pelvis, or hipbone. A ball at the end of the femur, called the femoral head, fits in a socket (the acetabulum) in the pelvis to allow a wide range of motion. During a traditional hip replacement, which lasts from 1 to 2 hours, the surgeon makes a 6- to 8-inch incision over the side of the hip through the muscles and removes the diseased bone tissue and cartilage from the hip joint, while leaving the healthy parts of the joint intact. Then the surgeon replaces the head of the femur and acetabulum with new, artificial parts. The new hip is made of materials that allow a natural gliding motion of the joint. In recent years, some surgeons have begun performing what is called a minimally invasive, or mini-incision, hip replacement, which requires smaller incisions and a shorter recovery time than traditional hip replacement. Candidates for this type of surgery are usually age 50 or younger, of normal weight based on body mass index, and healthier than candidates for traditional surgery. Joint resurfacing is also being used. Regardless of whether you have traditional or minimally invasive surgery, the parts used to replace the joint are the same and come in two general varieties: cemented and uncemented. Cemented parts are fastened to existing, healthy bone with a special glue or cement. Hip replacement using these parts is referred to as a “cemented” procedure. Uncemented parts rely on a process called biologic fixation, which holds them in place. This means that the parts are made with a porous surface that allows your own bone to grow into the pores and hold the new parts in place. Sometimes a doctor will use a cemented femur part and uncemented acetabular part. This combination is referred to as a hybrid replacement.

Is a cemented or uncemented prosthesis better?
The answer to this question is different for different people. Because each person’s condition is unique, the doctor and you must weigh the advantages and disadvantages. Cemented replacements are more frequently used for older, less active people and people with weak bones, such as those who have osteoporosis, while uncemented replacements are more frequently used for younger, more active people. Studies show that cemented and uncemented prostheses have comparable rates of success. Studies also indicate that if you need an additional hip replacement, or revision, the rates of success for cemented and uncemented prostheses are comparable. However, more long-term data are available in the United States for hip replacements with cemented prostheses, because doctors have been using them here since the late 1960s, whereas uncemented prostheses were not introduced until the late 1970s. The primary disadvantage of an uncemented prosthesis is the extended recovery period. Because it takes a long time for the natural bone to grow and attach to the prosthesis, a person with uncemented replacements must limit activities for up to 3 months to protect the hip joint. Also, it is more common for someone with an uncemented prosthesis to experience thigh pain in the months following the surgery, while the bone is growing into the prosthesis.

Preparation for Surgery and Recovery
People can do many things before and after they have surgery to make everyday tasks easier and help speed their recovery.

Before Surgery

What can be expected immediately after surgery?
You will be allowed only limited movement immediately after hip replacement surgery. When you are in bed, pillows or a special device are usually used to brace the hip in the correct position. You may receive fluids through an intravenous tube to replace fluids lost during surgery. There also may be a tube located near the incision to drain fluid, and a type of tube called a catheter may be used to drain urine until you are able to use the bathroom. The doctor will prescribe medicine for pain or discomfort. On the day after surgery or sometimes on the day of surgery, therapists will teach you exercises to improve recovery. A respiratory therapist may ask you to breathe deeply, cough, or blow into a simple device that measures lung capacity. These exercises reduce the collection of fluid in the lungs after surgery. As early as 1 to 2 days after surgery, you may be able to sit on the edge of the bed, stand, and even walk with assistance. While you are still in the hospital, a physical therapist may teach you exercises such as contracting and relaxing certain muscles, which can strengthen the hip. Because the new, artificial hip has a more limited range of movement than a natural, healthy hip, the physical therapist also will teach you the proper techniques for simple activities of daily living, such as bending and sitting, to prevent injury to your new hip.

Recovery and Rehabilitation:
Usually, people do not spend more than 3 to 5 days in the hospital after hip replacement surgery. Full recovery from the surgery takes about 3 to 6 months, depending on the type of surgery, your overall health, and the success of your rehabilitation.