Total hip replacement surgery replaces the upper end of the thighbone (femur) with a metal ball and resurfaces the hip socket in the pelvic bone with a metal shell and plastic liner. This surgery may be considered following a hip fracture (breaking of the bone) or for a person who has severe arthritis.
Various types of arthritis may affect the hip joint. Osteoarthritis, a degenerative joint disease that affects mostly middle-aged and older adults, may cause the breakdown of joint cartilage and adjacent bone in the hips. Rheumatoid arthritis, which causes inflammation of the synovial membrane and results in excessive synovial fluid, may lead to pain and stiffness. Traumatic arthritis (arthritis caused by injury) may cause damage to the articular cartilage of the hip.
The goal of total hip replacement surgery is to replace the parts of the hip joint that have been damaged (or worn out) and to relieve hip pain that cannot be controlled with other treatments.
A traditional hip replacement involves an incision several inches long over the hip joint. A newer approach called minimally invasive hip replacement uses one or two smaller incisions to perform the procedure. The minimally invasive procedure, however, is not suited for all total hip replacement candidates. The physician will determine the best procedure for the patient, based on their situation.
Reasons for the Procedure
Hip replacement surgery is a treatment for pain and disability in the hip. The most common condition that results in the need for hip replacement surgery is osteoarthritis.
Osteoarthritis is characterized by the loss of joint cartilage in the hip. Damage to the cartilage and bones limits movement and may cause pain. Patients with severe degenerative joint disease may be unable to do normal activities that involve bending at the hip, such as walking or sitting. There are other forms of arthritis, such as rheumatoid arthritis and arthritis that results from a hip injury, can also lead to degeneration of the hip joint.
The decision to replace the painful hip with an artificial one is a joint decision between the patient and surgeon. Other alternative treatments may first be used, including but not limited to assistive walking devices, physical therapy and anti-inflammatory medications.
What happens before surgery?
In addition to a complete medical history, the surgeon may perform a complete physical examination, including x-rays, to ensure that the patient is in good health before undergoing surgery. In additions, the patient may also need medical clearance and undergo blood tests (or any other ordered test). It is a good idea that the patient attends our pre-operative total joint replacement class to understand what to expect in the hospital as well as post discharge from the hospital.
How will the worn out hip be replaced with an artificial hip?
Although each procedure varies, generally the surgery to replace a hip will last up to two hours. The physician will remove the damaged parts of the hip joint and replace them with the prosthesis. The hip prosthesis is made up of a stem that goes into the femur (thighbone), the ball (head joint) that fits into the stem, and a cup that is inserted into the socket of the hip joint. The stem and cup are made of metal. The ball may be made of metal or ceramic. The cup has a liner that may be made of plastic or ceramic. The two most common types of artificial hip prostheses used are cemented prostheses and uncemented prostheses. A cemented prosthesis attaches to the bone with surgical cement. An uncemented prosthesis attaches to the bone with a porous surface onto which the bone grows to attach to the prosthesis. Sometimes, a combination of the two types is used to replace a hip.
Orthopedic surgeons sometimes use general anesthesia for joint replacement surgeries, which means the patient will be unconscious during surgery. However, most of the time they will use regional anesthesia, which means the patient can't feel the area of the surgery and is sedated. The choice of anesthesia depends on the surgeon, anesthesiologist, the patient's overall health and, to some degree, the patient's preference.
When the patient wakes up from surgery, there will be a bandage on the hip. A compression pump (SCDs), which squeezes the patient's legs to keep the blood circulating, preventing blood clots, will be in place while the patient is in bed.
The patient will be taught to do simple breathing exercises to help prevent congestion in the lungs while the activity level is decreased. This will be done with an incentive spirometer. The patient will also learn to move their feet up and down (ankle pumps) to flex the muscles and keep blood circulating.
Hip replacement surgeries usually require an in-hospital stay of one to two nights or more. Pain medication will be administered to keep the patient comfortable. Anticoagulants (blood thinners) will also be administered to help prevent blood clots. If the patient becomes nauseated or uncomfortable, medications will be administered by the nurse.
Rehabilitation after hip replacement surgery may vary depending on the surgeon's preferences. The surgeon will let the patient and physical therapist know what limitations there are.
In general, most patients will get out of the bed with help the day of surgery, or the day after, and will learn how to walk with a walker. The physical therapist and sometimes an occupational therapist will teach how to exercise, walk, and do activities such as dressing and cooking while the hip is healing. Depending on the type of surgery the patient has and the surgeon's instructions, the patient may learn the following precautions to keep the hip from dislocating:
- Avoid combinations of movement with the new hip. For example, do not sit with legs crossed because in that position, the patient is both bending the hip and bringing the hip across the body.
- The patient may be instructed to not bend the hip more than 90 degrees. If so, the therapist may suggest these ideas:
- Do not sit on low chairs, beds or toilets. It may be necessary to get a special riser for the toilet seat temporarily.
- Do not raise the knees higher than the hip.
- Do not lean forward while sitting down or when sitting down and standing up.
- Do not bend over more than 90 degrees, meaning the patient will not be able to tie their shoes for a while.
- For about 8 weeks, the surgeon may not want the leg to cross the center of the body toward the other leg. If so, the therapist may suggest these ideas:
- Do not cross legs.
- Be careful getting in and out of bed or a car, so that the leg does not cross the imaginary line in the middle of the body.
- The surgeon may not want the leg to rotate in or too far out. If so, the therapist may suggest the patient keep their toes pointing forward or slightly out.
In order for the patient to get the most benefit from hip replacement surgery, it is important to take part in physical therapy while in the hospital and to perform exercise as instructed at home.
During the hospital stay, a case manager will assess the patient and their goals for discharge. The case manager will help with equipment that may be needed at home, set up with a home health agency and inpatient rehabilitation if needed.