HIP REPLACEMENT SURGERY DIAGNOSTIC TESTS

The doctor may also order one or more specialized tests, depending on the known or suspected causes of the pain:
• Aspiration. Aspiration is a procedure in which fluid is withdrawn from the joint by a needle and sent to a laboratory for analysis. It is done to check for infection in the joint. • Arthrogram. An arthrogram is a special type of x ray in which a contrast dye is injected into the hip to outline the cavity surrounding the joint.

• Magnetic resonance imaging (MRI). An MRI uses a large magnet, radio waves, and a computer to generate images of the head and back. It is helpful in diagnosing avascular necrosis.

• Computed tomography (CAT) scan. A CAT scan is anotherspecialized type of x ray that uses computers to generate three-dimensional images of the hip joint. It is most often used to evaluate the severity of avascular necrosis and to obtain a more accurate picture of malformed or unusually shaped joints.

• Bone densitometry test. This test measures the density or strength of the patients bones. It does not require injections; the patient lies flat on a padded table while an imager passes overhead. This test is most often given to patients at risk for osteoporosis or other disorders that affect bone density.

Preoperative preparation
Hip replacement surgery requires extensive and detailed preparation on the patients part because it affects so many aspects of life.

LEGAL AND FINANCIAL CONSIDERATIONS. In the United States, physicians and hospitals are required to verify the patients insurance benefits before surgery and to obtain precertification from the patients insurer or from Medicare. Without health insurance, the total cost of a hip replacement as of 2002 can run as high as $35,000 - $45,000. In addition to insurance documentation, patients are legally required to sign an informed consent form prior to surgery. Informed consent essentially signifies that the patient is a knowledgeable participant in making healthcare decisions. The doctor will discuss all of the following with the patient before he or she signs the form: the nature of the surgery; reasonable alternatives to the surgery; and the risks, benefits, and uncertainties of each option. Informed consent also requires the doctor to make sure that the patient understands the information that has been given.

MEDICAL CONSIDERATIONS. Patients are asked to do the following in preparation for hip replacement surgery:
• Get in shape physically by doing exercises for strengthening the heart and lungs, building up the muscles around the hip, and increasing the range of motion of the hip joint. Many clinics and hospitals distribute illustrated pamphlets of preoperation exercises.

• Loose weight if the surgeon recommends it.

• Quit smoking. Smoking weakens the cardiovascular system and increases the risks that the patient will have breathing difficulties under anesthesia.

• Make donations of ones own blood for storage in case a transfusion is necessary during surgery. This procedure is known as autologous blood donation; it has the advantage of avoiding the risk of transfusion reactions or transmission of diseases from infected blood donors.

• Have necessary dental work completed before the operation. This precaution is necessary because small numbers of bacteria enter the bloodstream whenever a dentist performs any procedure that causes the gums to bleed. Bacteria from the mouth can be carried to the site of the hip replacement and cause an infection.

• Discontinue taking birth control pills and any anti-inflammatory medications (aspirin or NSAIDs) two weeks before surgery. Most doctors also recommend discontinuing any alternative herbal preparations at this time, as some of them interact with anesthetics and pain medications.

LIFESTYLE CHANGES. Hip replacement surgery requires a long period of recovery at home after leaving the hospital. Since the patients physical mobility will be limited, he or she should do the following before the operation:
• Arrange for leave from work, help at home, help with driving, and similar tasks and commitments.

• Obtain a handicapped parking permit.

• Check the house or apartment living quarters thoroughly for needed adjustments to furniture, appliances, lighting, and personal conveniences. People recoveringfrom hip replacement surgery must minimize bending, stooping, and any risk of falling. There are several good guides available that describe household safety and comfort considerations in detail.

• Stock up on nonperishable groceries, cleaning supplies, and similar items in order to minimize shopping.

• Have a supply of easy-care clothing with elastic waistbands and simple fasteners in front rather than complicated ties or buttons in the back. Shoes should be slipons or fastened with Velcro.

Many hospitals and clinics now have preop classes for patients scheduled for hip replacement surgery. These classes answer questions regarding preparation for the operation and what to expect during recovery, but in addition they provide opportunities for patients to share concerns and experiences. Studies indicate that patients who have attended preop classes are less anxious before surgery and generally recover more rapidly.

Aftercare
Aftercare following hip replacement surgery begins while the patient is still in the hospital. Most patients will remain there for five to 10 days after the operation. During this period, the patient will be given fluids and antibiotic medications intravenously to prevent infection. Medications for pain will be given every three to four hours, or through a device known as a PCA (patient-controlled anesthesia). The PCA is a small pump that delivers a dose of medication into the IV when the patient pushes a button. To get the lungs back to normal functioning, a respiratory therapist will ask the patient to cough several times a day or breathe into blow bottles.

Aftercare during the hospital stay is also intended to lower the risk of a venous thromboembolism (VTE), or blood clot in the deep veins of the leg. Prevention of VTE involves medications to thin the blood; exercises for the feet and ankles while lying in bed; and wearing thromboembolic deterrent (TED) or deep vein thrombosis (DVT) stockings. TED stockings are made of nylon (usually white) and may be knee-length or thigh-length; they help to reduce the risk of a blood clot forming in the leg vein by putting mild pressure on the veins. TED stockings are worn for two to six weeks after surgery. Physical therapy is also begun during the patients hospital stay, often on the second day after the operation.

The physical therapist will introduce the patient to using a walker or crutches and explain how to manage such activities as getting out of bed or showering without dislocating the new prosthesis. In addition to increasing the patients level of physical activity each day, the physical therapist will help the patient select special equipment for recovery at home. Commonly recommended devices include a reacher for picking up objects without bending too far; a sock cone and special shoehorn; and bathing equipment. Following discharge from the hospital, the patient may go to a skilled nursing facility, rehabilitation center, or directly home. Ongoing physical therapy is the most important part of recovery for the first four to five months following surgery.

Most HMOs in the United States allow home visits by a home health aide, visiting nurse, and physical therapist for three to four weeks after surgery. The physical therapist will monitor the patients progress, as well as suggest specific exercises to improve strength and range of motion. After the home visits, the patient is encouraged to take up other forms of physical activity in addition to the exercises; swimming, walking, and pedaling a stationary bicycle are all good ways to speed recovery. The patient may take a mild medication for pain (usually aspirin or ibuprofen) 30 - 45 minutes before an exercise session if needed.

Most patients can start driving six to eight weeks after the operation and return to work full time after eight to 10 weeks, depending on the amount and type of physical exertion their jobs requires. Some patients arrange to work on a part-time basis until their normal level of energy returns.