Patient education is important for Dr. LaButti, working closely with you to make sure you understand your condition and your treatment for the best results. Getting the best results from your hip surgery or other treatment takes a partnership between you and your surgeon.

The following sections provide detailed clinical information about the hip, joint replacement and other information from Dr. LaButti.

About the hip joint.
The hip is one the body’s largest weight-bearing joints. The hip is composed of the rounded head of the femur (thigh bone) joining the acetabulum (socket) at the pelvis in a ball-and-socket arrangement. In a healthy joint, articular cartilage lines the acetabulum and covers the head of the femur. These smooth durable surfaces ensure that the ball glides easily within the socket, a movement that should be painless. Tough bands of tissue called ligaments help reinforce the hip for stability. The entire joint is lined with a thin, smooth tissue called synovial. In a healthy hip, this membrane produces a small amount of fluid that lubricates and almost eliminates friction in the hip.

Normally, all of the parts of your hip work in harmony, allowing you to move easily without pain.

Why are total hip replacements performed?

Total hip replacements are often recommended by orthopedic surgeons for patients who:

• have a painful, disabling joint disease of the hip resulting from a severe form of arthritis;
• are not likely to achieve satisfactory results from less invasive procedures, such as arthoscopy, medication, physical therapy, or dietary supplements.

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Common Causes of Hip Pain

Trauma by Direct or Indirect Injury.

Fractures of the bone that extend into the knee joint can injure articular and meniscal cartilage, often leaving irregularities of the joint surfaces and sometimes loose fragments of cartilage. These irregularities and loose fragments can cause painful locking or grinding within the hip, resulting in irregular wear on the joint surfaces and post-traumatic arthritis.

When blunt trauma occurs to the hip without fracture, abnormal compression forces applied to the articular cartilage can result in microscopic injury to cartilage and underlying bone (bone bruise). This lessens the ability of the articular cartilage to handle normal joint forces and may lead to changes in the knee similar to osteoarthritis.

Indirect Injury Ligament injury results from abnormal rotational or bending stress applied to the hip. Residual instability of the hip produces abnormal translational stresses to the articular cartilage and labrum causing pain and swelling. Over time, these abnormal stresses can lead to degeneration of the joint surfaces.

Injury to the labrum can occur with fractures or blunt trauma. The torn labrum may get caught within the joint causing painful snapping or locking of the hip.

Labrum Injury The labrum is a fibrous ring of cartilage that encircles the acetabular socket of the hip joint. It effectively extends the acetabular rim beyond the equator of the femoral head improving stability.

Occasionally, tears can occur causing pain generally localized in the groin region, exacerbated with activity and certain extremes of motion such as internal or external rotation of the leg. Painful snapping sensations are not uncommon.

MRI is usually diagnostic, treatment usually is non-operative. Arthroscopic surgery of the hip can be performed in refractory cases. The procedure involves either repair or removal of the cartilage tear.

Anterior Femoral Acetabular Impingement (FAI). This is an abutment that occurs between the proximal femur and acetabular rim arising from anatomic normalities of these structures. There is emerging clinical evidence implicating FAI as a factor in causing early osteoarthritis.

The abnormal repetitive contact occurring during motion, particularly flexion and internal rotation can lead to injury of the acetabular labrum and adjacent acetabular cartilage.

Surgical treatment focuses on improving hip motion and removing the boney abnormalities causing femoral abutment against the acetabular rim. This can be performed by arthroscopic or traditional open techniques.

Arthritis is an inflammation of the joints that is painful and can even change the structure of the joint. Though often considered a disease of the elderly, it can strike at any age. There are several types of arthritis, but the most common is degenerative joint disease or osteoarthritis. This disease affects more than 20 million people in the United States.

Osteoarthritis is a joint disease that mostly affects the cartilage. Cartilage is the slippery tissue that covers the ends of bones in a joint. Healthy cartilage allows bones to glide over one another easily. It also absorbs energy and cushions the ends of bones in joints. In Osteoarthritis, the surface layer of the cartilage breaks down and wears away. This allows bones under the cartilage to rub together, causing pain, swelling and loss of motion of the joint. Over time, the joint may lose its normal shape. Bone spurs (small growths called osteophytes) may grow on the edges of the joint. Bits of bone and cartilage can break off and float inside the joint space. This causes more pain and damage.

Symptoms include pain in the involved joint that is typically worse with activity and relieved by rest, stiffness after periods of immobility, instability, limitation of motion, muscle atrophy and weakness. Osteoarthritis can result from ligament or labral injury and can be hereditary. Repetitive use, such as athletics, may be implicated as well.

If not treated, osteoarthritis can lead to disability. Medications, weight loss, exercise and walking aids can reduce pain and disability. In severe cases, hip replacement surgery may be helpful.

Osteoarthritis most often occurs at the ends of the fingers, thumbs, neck, lower back, knees and hips. The cause of the disease for the most part is undetermined, but several factors may contribute including:

• Being overweight.
• The aging process.
• Joint injury.
• Stresses on the joints from certain jobs and sports activities.

Osteoarthritis of the hip can cause pain, stiffness and severe disability. People may feel the pain in their hips, or in their groin, inner thigh, buttocks or knees. Walking aids, such as canes or walkers, can reduce stress on the hip.

Osteoarthritis in the hip may limit moving and bending. This can make daily living activities such as dressing and foot care a challenge. Walking aids, medications and exercise can help relieve pain and improve motion. The doctor may recommend hip replacement surgery if the pain is severe and not relieved by other methods.

Rheumatoid arthritis causes the synovium to become thickened and inflamed. In turn, too much synovial fluid is produced within the joint space, which causes a chronic inflammation that damages the cartilage. This results in cartilage loss, pain and stiffness. Rheumatoid arthritis affects women about three times more often than men, and may affect other organs of the body.

Avascular necrosis is a disease resulting from the temporary or permanent loss of blood supply to the bones. Without blood, the bone tissue dies and causes the bone to collapse. If the process involves the bones near a joint, it often leads to collapse of the joint surfaces. This disease is also known as osteonecrosis, aseptic necrosis, and ischemic bone necrosis.

Although it can happen in any bone, avascular necrosis most commonly affects the ends (epiphysis) of long bones such as the femur, the bone extending from the knee joint to the hip joint. Other common sites include the upper arm bone, knees, shoulders and ankles. The disease may affect just one bone, more than one bone at the same time, or more than one bone at different times. Avascular necrosis usually affects people between 30 and 50 years of age; about 10,000 to 20,000 people develop avascular necrosis each year. Orthopedic doctors most often diagnose the disease.

The amount of disability that results from avascular necrosis depends on what part of the bone is affected, how large an area is involved, and how effectively the bone rebuilds itself. The process of bone rebuilding takes place after an injury as well as during normal growth. Normally, bone continuously breaks down and rebuilds an old bone is reabsorbed and replaced with new bone. The process keeps the skeleton strong and helps it to maintain a balance of minerals. In the course of avascular necrosis, however, the healing process is usually ineffective and the bone tissues break down faster than the body can repair them. If left untreated, the disease progresses, the bone collapses, and the joint surface breaks down, leading to pain and arthritis.

Symptoms are abrupt onset of pain initially only during weight bearing and later during non-weight bearing and even while at rest. In some patients, the pain becomes unbearable as the disease progresses, whereas in others, it does not.

Causes of Avascular necrosis:
Avascular necrosis has several causes. Loss of blood supply to the bone can be caused by an injury (trauma-related avascular necrosis or joint dislocation) or by certain risk factors (non-traumatic avascular necrosis), such as some medications (steroids), blood coagulation disorders, or excessive alcohol use. Increased pressure within the bone also is associated with avascular necrosis. The pressure within the bone causes the blood vessels to narrow, making it hard for the vessels to deliver enough to blood to the bone cells.

Injury:
When a joint is injured, as in a fracture or dislocation, the blood vessels may be damaged. This can interfere with the blood circulation to the bone and lead to trauma-related avascular necrosis. Studies suggest that this type of avascular necrosis may develop in more than 20 percent of people who dislocate their hip joint.

Steroid medications:
Corticosteroids such as prednisone are commonly used to treat inflammatory diseases, such as systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel disease, and vasculitis. Studies suggest that long-term, systemic (oral or intravenous) corticosteroid use is associated with 35 percent of all cases of non-traumatic avascular necrosis. However, there is no known risk of avascular necrosis associated with the limited use of steroids. Patients should discuss concerns about steroid use with their doctor.

It is not clear exactly how the use of corticosteroids sometimes can lead to avascular necrosis. They may interfere with the body’s ability to break down fatty substances. These substances then build up in and clog the blood vessels. This reduces the amount of blood that gets to the bone. Some studies suggest that corticosteroid-related avascular necrosis is more severe and more likely to affect both hips (when occurring in the hip) than avascular necrosis resulting from other causes.

Alcohol use:
Excessive alcohol use and corticosteroid use are two of the most common causes of nontraumatic avascular necrosis. In people who drink an excessive amount of alcohol, fatty substances may block blood vessels, causing a decreased blood supply to bones that result in avascular necrosis.

Other risk factors:
Other risk factors or conditions associated with non-traumatic avascular necrosis Gaucher’s disease, pancreatitis, radiation treatments and chemotherapy, decompression disease, and blood disorders such as sickle cell disease.

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Non-operative treatments for Osteoarthritis of the hip.
Osteoarthritis treatment plans often include ways to manage pain and improve function. Such plans can involve exercise, rest and joint care, pain relief, weight control, medicines, surgery and nontraditional treatment approaches.

• Exercise is one of the best treatment options. Exercise can improve mood and outlook, decrease pain, increase flexibility, improve the heart and blood flow, maintain weight, and promote general fitness. The amount and form of exercise will depend on the joints affected, their stability and whether a joint replacement has already been done.
• Rest and joint care treatment plans include regularly scheduled rest. Patients must learn to recognize the body’s signals to stop or slow down. Canes and orthotics are used to protect joints and take pressure off them. Braces provide extra support for the weakened joints. They also keep the joint in proper position during sleep or activity. Splints should only be used for limited periods because joints and muscles need to be exercised to prevent stiffness and weakness.
• Pain relief can include nondrug and drug protocols. Warm towels, hot packs or a warm bath or shower can relieve joint pain and stiffness. In some cases, cold packs can relieve pain or numb a sore area. Always check with your physician or physical therapist what treatment is best. For osteoarthritis in the knee, patients may wear insoles or cushioned shoes to redistribute weight and reduce joint stress.

For more severe pain, patients will often have to turn to pain medication. Physicians prescribe medicines to eliminate or reduce pain and to improve functioning. Physicians must consider the intensity of the pain and potential side effects of the medicine. The following types of medicines are commonly used in treating osteoarthritis:

• Acetaminophen: a pain reliever that does not reduce swelling. It does not irritate the stomach and is less likely to cause long-term side effects than nonsteroidal anti-inflammatory drugs (NSAIDs).
• NSAIDs: they fight inflammation and relieve pain. Some can be purchased over the counter and others require a prescription. Each is a different chemical, and affects the body differently. NSAIDs can cause stomach irritation and affect kidney function. The longer the person uses NSAIDs , the more likely they are to have side effects ranging from mild to serious. Always tell your health care provider what medications you are taking, since some drugs may interact with potentially dangerous side effects.
• COX-2 inhibitors: Are a new class of NSAIDs that reduce inflammation with fewer gastrointestinal side effects. These medications occasionally are associated with harmful reactions ranging from mild to severe. Always consult your physician or pharmacists if you have any questions or concerns.
• Other medications:
  Topical pain-relieving creams, rubs and sprays, which are applied directly to the skin. Mild narcotic painkillers, which are very effective, may be addictive and are not commonly used. Corticosteroids are powerful anti-inflammatory hormones made naturally in the body or manmade for use as medicine. Corticosteroids may be injected into the affected joints for temporary pain relief. This is a short-term measure, and is not recommended for more than two or three treatments per year.

Other medications: Topical pain-relieving creams, rubs and sprays, which are applied directly to the skin. Mild narcotic painkillers, which are very effective, may be addictive and are not commonly used. Corticosteroids are powerful anti-inflammatory hormones made naturally in the body or manmade for use as medicine. Corticosteroids may be injected into the affected joints for temporary pain relief. This is a short-term measure, and is not recommended for more than two or three treatments per year.

Glucosamine works to normalize damaged joint cartilage and protect it from further harm. The recommended dosage of glucosamine sulfate for osteoarthritis is 1,500 mg daily. It may take anywhere from one to four months to experience partial pain relief.

Patients who include chondroitin sulfate have a slight additional benefit. Other joint-protective compounds include:

• Vitamins A, B6, and C, and the minerals copper and zinc, are all required for the bod’s manufacture of collagen and normal cartilage.
• Vitamins A and C, when used in combination, may help slow down the deterioration of afflicted cartilage.
• Vitamins C and E, used in combination, protect cartilage from free-radical destruction.

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The right hip replacement for you.
Surgeons can choose from a wide variety of hip replacement implants produced by various manufacturers. Materials and clinical engineering of these implants vary, and typically surgeons only use one or two product lines based upon the results they see afterward and ease of using the components. When selecting the implant for your hip replacement surgery your surgeon will consider:

• Your age, activity level, weight and degree of arthritis.
• The implants track record of long-term stability and adhesion called fixation.
• The implant’s material.
• The implant’s ability to reestablish your normal function.
• The surgeon’s comfort level with the surgical instruments associated with the preferred implant.
• The surgeon’s confidence in the implant’s clinical success rate and product quality.

When considering the right hip replacement for any patient, the surgeon categorizes the patient into three groups; low demand, mid-demand and high demand.

Low demand patients are usually older and more sedentary with poorer quality bone. A cemented femoral component is usually considered with an un-cemented acetabular component. Fixation of the acetabular component may be augmented with screws. A metal ball that articulates on an ultra high molecular weight, highly cross-linked polyethylene acetabular liner is usually chosen. An un-cemented or press-fit femoral component can also be considered, depending on the patient’s bone quality.

High demand patients are usually younger, more active and with better quality bone. An un-cemented or press-fit femoral component is usually the standard with an un-cemented acetabular component. The bearing surface can be metal on metal or ceramic on ceramic. Metal on metal bearing surfaces are usually avoided in patients with heart, lung and kidney disorders as well as women of child bearing age.

The mid-demand patient is as the name implies; somewhere between the low and high demand patients. The femoral component may be cemented or un-cemented, depending on the patient’s bone quality. The acetabular component is usually un-cemented. Fixation can be augmented with screws. A ceramic ball on an ultra high molecular weight, highly cross-linked polyethylene liner has been demonstrated to give the best longevity in this group of patients.

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Risks of hip replacement surgery.
As with any major surgery, there are potential risks and complications you should be aware of before you undergo total hip replacement surgery. A major cause of failure in total hip replacement is loosening of the prosthesis, either mechanical or by bacterial infection.

There is a very small chance of infection occurring (less than 1 out of 100 in first time hip replacements and less than 2 out of 100 for revision hip replacements), but if infection occurs it is a very difficult problem to treat. If infection occurs, salvage of the prosthesis is successful dependent on several factors including:

• Type of bacteria.
• Patient health.
• Length of time from hip replacement surgery.
• How long the infection has been present.

In late or chronic infections, removal of the prosthesis is usually necessary. A spacer made of antibiotic loaded cement is placed and re-implantation of a new prosthesis is planned after several weeks of intravenous antibiotics. This two stage procedure is usually successful in eradicating the infection.

Great measures are taken to help reduce infections, which include:

• The use of sterile instruments, drapes, gowns and gloves.
• The patient’s leg is thoroughly cleaned with an antiseptic agent and all other areas are covered with sterile drapes.
• Space Helmets (body exhaust filtration systems) are worn by the surgical team, mainly during revision surgery.
• The patient is given prophylactic antibiotics prior to surgery and is generally continued for 24 hours following surgery longer in cases of revision surgery.
• Because a bacterial infection from your mouth could infect your new joint, complete all dental work before surgery and always consult your physician before scheduling any post-operative dental work.

Mechanical loosening is when the implant loosens from their bony attachment, the motion between the bone and implant will cause pain, bone destruction and ultimately failure. There is approximately a 3% chance of loosening in 10 to 15 years in an ideal candidate for hip replacement. In non-ideal candidates such as patients who are younger, more active or excessively overweight, chances of loosening increase. Excessive wear can contribute to loosening and leading to revision surgery.

The most common problem that may happen soon after hip replacement surgery is hip dislocation. Because the artificial ball and socket are smaller than the normal ones, the ball can become dislodged from the socket if the hip is placed in certain positions. The most dangerous position usually is pulling the knees up to your chest.

Other complications include the formation of blood clots in the leg or pelvis. Blood clots cause chronic swelling in the affected leg and can travel to the lungs causing a pulmonary embolism, a potentially life threatening problem. Be assured your doctor will take all necessary precautions to avoid blood clots that include:

• The use of blood thinning medications.
• Elastic stockings.
• The use of plastic boots that inflate with air to compress the muscles in your leg.
• Early mobilization beginning on the first day after surgery.

Other risks include strain on the heart and lungs resulting in heart attack, stroke or death; anesthetic risks; and possible damage to nerves, arteries and veins that can affect the circulation and function of the leg.

Overall, the risks are usually quite low and the chance of success greatly outweighs the chance of failure. If you have any concerns, always be sure to speak with your doctor.

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Hip replacement surgery.
Hip replacement surgery is considered elective surgery and is not a conservative operation. Only after pain medications, anti-inflammatory drugs or even minor surgery have failed to relieve pain, should this surgery be considered. In this procedure, joint surfaces are resurfaced with manmade materials such as plastic, metal or ceramic. There are a wide variety of implants available, but all of them consist of two basic components.

1. The femoral component is composed of a stem made of cobalt chrome or titanium and a ball made of cobalt chrome or ceramic. The stem extends into the canal of the thigh bone (femur) and is sometimes secured with cement.
2. The acetabular component or cup is made of cobalt chrome or titanium. It is usually placed in the socket without cement and fixation may be augmented with screws. A ceramic or plastic liner snaps into this component and articulates with the ball of the femoral component.

A non-cemented prosthesis has been developed for use in younger or more active patients. The prosthesis is coated with textured metal and/or bone growth enhancing substance called hydroxyapatite, which improves the bones ability to grow onto the prosthesis

An ideal candidate for hip replacement is a patient who is over 60, relatively sedentary, has normal mental capacity and is not overweight. The high risk patients are those under 60, over weight, excessively active or who have had previous hip surgery that has failed. The expected benefits from hip replacement should be 95% chance of relieving your pain and restoring motion and function for routine activities of daily living.

Always ask your orthopedic surgeon if you are an ideal candidate for total hip replacement surgery and what risks are involved.

About Revision Hip Surgery.
Revision hip surgery replaces worn total hip parts and damaged bone. Metal, plastic or ceramic components are used to restore normal hip joint stability.

• The old plastic liner and metal socket are removed.
• Morselized bone is used to strengthen the socket and fill bone cavities. Allograft may be used for support. It may also be necessary to use a wire mesh to hold the socket’s shape.
• The new metal socket is pressed into place.
• A new metal, plastic or ceramic liner is pressed into place.
• An osteotomy may be performed to remove the old femoral component.
• After the bone segments are cleaned of the old cement, the new metal femoral component is pressed or cemented into place.
• Wire is used to close the bone segments tightly around the components. The wires may also hold struts of bone graft in place to strengthen the femur.
• A new metal or ceramic ball is placed on the femoral component.
• The hip socket with its new liner and shell and put together with the femur to form a new hip joint.

Facts about total hip replacement:

• Approximately 300,000 hip replacements are performed in the U.S. each year.
• 64 percent of hip replacement patients are in women.
• 34 percent of hip replacement patients are between 40 and 64 years of age.
• 90 to 95 percent of hip replacements are successful for up to 10 years.
• Younger, more active patients are now receiving hip replacements and are demanding high technology implants that will last longer and support their active lifestyles.

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