An exciting new alternative to total hip replacement is now available in the United States. Used successfully for years around the globe, the BIRMINGHAM HIP Resurfacing System has recently been approved by the Food and Drug Administration for use in the United States. Now, patients suffering from hip pain due to arthritis, dysplasia or avascular necrosis can benefit from its conservative approach to treatment.
Because this technologically advanced surgical procedure resurfaces rather than replaces the end of your femur (thighbone), you may participate in more strenuous physical activity with an implant that is potentially more stable and longer-lasting than traditional total hip replacements. And if future revision surgery is required, it may be a less complex and less traumatic procedure.
In fact, a 1,626-hip study of the effectiveness of the technique found that 99.5-percent of patients responded they were "Pleased" or "Extremely pleased" with the results of their BIRMINGHAM HIP Resurfacing surgery.
Who is a Candidate for Hip Resurfacing?
Hip resurfacing is intended for young, active adults who are under 60 years of age and in need of a hip replacement. Adults over 60 who are living non-sedentary lifestyles may also be considered for this procedure. However, this can only be further determined by a review of your bone quality.
There are certain causes of hip arthritis that result in extreme deformity of either the head of the femur or the acetabulum (hip socket). These cases are usually not candidates for hip resurfacing.
Talk with your orthopaedic surgeon to determine if hip resurfacing is the right option for you.
Until just recently, your orthopedist would likely be recommending total hip replacement surgery at this point of your disease state. While it is clearly a more bone-sacrificing procedure than hip resurfacing, total hip replacement is a safe and effective surgery, and is performed more than 300,000 times per year in the United States.
As you may know, total hip replacement requires the removal of the femoral head and the insertion of a hip stem down the shaft of the femur. Hip resurfacing, on the other hand, preserves the femoral head and the femoral neck. During the procedure, your surgeon will only remove a few centimeters of bone around the femoral head, shaping it to fit tightly inside the BIRMINGHAM HIP Resurfacing implant.
Your surgeon will also prepare the acetabulum for the metal cup that will form the socket portion of the ball-and-socket joint. While the resurfacing component slides over the top of the femoral head like a tooth cap, the acetabular component is pressed into place much like a total hip replacement component would be.
The BIRMINGHAM HIP Resurfacing implant is not brand new. It has been in use around the world since 1997 and has since been implanted more than 60,000 times. It is new to the United States, however, where it was approved for use by the Food and Drug Administration in May 2006.
Although hip resurfacing is not a new concept, the technology behind the ground-breaking BIRMINGHAM HIP was developed by British orthopedic surgeons Mr. Derek McMinn and Mr. Ronan Treacy. The two surgeons now train orthopedists from around the globe on behalf of London-based medical device manufacturer Smith & Nephew. US surgeons given access to this implant may travel to England for specialized training or may train at one of the few US centers capable of hosting these focused sessions.
The benefits to patients of the BIRMINGHAM HIP Resurfacing technique and implant are clear. The implant's head size, its bearing surfaces, and its bone-sparing technique make it a preferred choice for young, active patients. While the implant's rate of survivorship is comparable to standard total hip replacements after five years, these three key advantages set the resurfacing technique and implant apart from its total hip replacement counterparts.
The most noticeable aspect of this implant is its size. While it closely matches the size of your natural femoral head, it is substantially larger than the femoral head of a total hip replacement. This increased size translates to greater stability in your new joint, and it decreases the chance of dislocation of your implant after surgery.
Dislocation is a leading cause of implant failure in total hip replacement. While total hip implants dislocate at a rate of one to three-percent over the lifetime of the implant, a study of 2,385 BIRMINGHAM HIP Resurfacing patients found that dislocation occurred in only 0.3-percent of cases five years after surgery.
BIRMINGHAM HIP Resurfacing takes advantage of one of the orthopaedic medical industry's most technologically advanced bearing surfaces. That means that the surfaces of the ball and the socket are made from materials that dramatically reduce joint wear when compared to traditional hip implant materials.
In this case, both the ball and socket are made from tough, smooth cobalt chrome metal. Traditionally, only the ball is made from cobalt chrome, and the socket is lined with a plastic cup. While this plastic cup has some design advantages, it does wear out over the course of many years since it rubs against the metal ball at a rate of nearly two million footsteps per year in physically active adults.
The plastic particles released into the area around the joint as a result of this plastic wear can lead to a condition called osteolysis, which causes the bone around the implant to soften, become unstable, and ultimately a corrective surgery and new implant are required.
However, when both surfaces of a hip implant are made from cobalt chrome, wear particles are reduced by 97-percent1, thus potentially extending the life of the implant.
There may be risks associated with metal-on-metal hip implants, though. While no evidence has been established on the subject, some are concerned that the increased level of metal ions found in the blood of metal-on-metal hip recipients may have negative effects on the human body. For this reason, some surgeons may not implant such a device in a patient with kidney disease (since healthy kidneys filter ions from your body) or in women who are or may become pregnant.
Perhaps the greatest benefit of the BIRMINGHAM HIP Resurfacing implant is the fact that it conserves substantially more bone than a total hip replacement. This is important for two key reasons.
First, unlike a total hip replacement, the BIRMINGHAM HIP Resurfacing preserves your natural femoral neck. It is this neck length and angle that determines the natural length of your leg, and since it is not removed and replaced with an artificial device during a resurfacing procedure, concerns regarding leg length discrepancy are virtually non-existent.
Second, if your surgeon should determine you need to have your BIRMINGHAM HIP implant replaced at some point in the future, you may undergo a regular total hip replacement surgery. If you had originally undergone total hip replacement instead of hip resurfacing, you would be dealing with a more traumatic and complex procedure and you would be receiving a more invasive implant.
Hip Resurfacing: Pre-op & Surgery Day
Once you and your orthopedic surgeon decide that hip resurfacing is right for you, the days and weeks leading up to surgery, as well as the day of surgery, require preparation. The following is a description of what you may expect.
You and your orthopedic surgeon may participate in an initial surgical consultation. This appointment may include pre-operative X-rays, a complete medical and surgical history, physical examination, and a comprehensive list of medications and allergies. During this visit, your orthopedic surgeon will likely review the procedure and answer any questions.
Your orthopedic surgeon may require that you have a complete physical examination by your internist or family physician, as you will need to be cleared medically before undergoing this procedure. Your surgeon may suggest that you consider donating your own blood to save in case you require it during surgery or in the event of a post-operative blood transfusion.
Preparation for the Hospital
You may want to bring the following items to the hospital:
- Clothing underwear, socks, t-shirts, exercise shorts for rehabilitation
- Footwear walking or tennis shoes for rehab, slippers for hospital room
- Walking aids walker, cane, wheelchair, or crutches if used prior to surgery
- Insurance information
Before Surgery, You Should Adhere to the Following:
- You should follow your regular diet on the day before your surgery.
- DO NOT EAT OR DRINK AFTER MIDNIGHT the night before surgery. On the morning of surgery, you may brush your teeth and rinse your mouth, but do not swallow any water.
- Follow your doctor's instructions regarding use of medication in the days leading to surgery. In some cases, a blood thinner may be ordered a few days before surgery. Generally, aspirin and non-steroidal anti-inflammatory medications should not be taken seven days prior to surgery.
- Try to get long, restful nights of sleep. A sleeping medication may be ordered the evening before surgery.
Day of Surgery
On the morning of surgery, once you are admitted to the hospital, you will be taken to the appropriate pre-surgical area where the nursing staff will take your vital signs, start intravenous (IV) fluids, and administer medications as needed. You will be asked to empty your bladder just prior to surgery, and to remove all jewelry, contacts, etc. (Rings not removed will be taped.) Once you change into a hospital gown, you will be placed on a stretcher, and transported to the operating room. The anesthesiologist will meet you and review the medications and procedures to be used during surgery.
Surgery and Recovery
When surgery is completed, you will be taken to the recovery room for a period of close observation. Your blood pressure, heart rate, respiration, and body temperature will be closely monitored by the recovery room staff. Special attention will be given to your circulation and sensation in your feet and legs. When you awaken and your condition is stabilized, you will be transferred to your room.
Although the protocols may vary from hospital to hospital, you may awaken to some or all of the following:
- A large dressing may have been applied to the surgical area.
- You may see a hemovac suction container with tubes leading directly into the surgical area. This device allows the nurses to measure and record the amount of drainage from the wound following surgery.
- An IV will continue post-operatively in order to provide adequate fluids. The IV may also be used for administration of antibiotics or other medications.
- A catheter may have been inserted into your bladder as the side effects of medication often make it difficult to urinate.
- An elastic hose may be applied to decrease the risk of deep vein thrombosis (DVT). A compression device may also be applied to your feet to further prevent DVT.
- A patient-controlled analgesia (PCA) device may be connected to your IV, allowing you to control the relative amount and frequency of pain medication. To prevent overdose, the unit is programmed to deliver a pre-defined amount of pain medication anytime you press the button of the machine.
Diseases of the Hip
There are four primary diseases of the hip that may indicate the need for BIRMINGHAM HIP Resurfacing.
Osteoarthritis of the hip is a disease which wears away the cartilage between the femoral head and the acetabulum, eventually causing the two bones to scrape against each other, raw bone on raw bone. When this happens, the joint becomes pitted, eroded and uneven. The result is pain, stiffness and instability, and in some cases, motion of the leg may be greatly restricted.
Patients with osteoarthritis often develop large bone spurs, or osteophytes, around the joint, further limiting motion.
Osteoarthritis is a common, degenerative disease, and although it most often occurs in patients over the age of 50, it can occur at any age, especially if the joint is in some way damaged.
Osteoarthritis of the hip is a condition commonly referred to as "wear and tear" arthritis. Although the degenerative process may accelerate in persons with a previous hip injury, many cases of osteoarthritis occur when the hip simply wears out. Some experts believe there may exist a genetic predisposition in people who develop osteoarthritis of the hip. Abnormalities of the hip due to previous fractures or childhood disorders may also lead to a degenerative hip. Osteoarthritis of the hip is the most common cause for both total hip replacement and hip resurfacing.
The first and most common symptom of osteoarthritis is pain in the hip or groin area during weight bearing activities such as walking. People with hip pain usually compensate by limping, or reducing the force on the arthritic hip. As a result of the cartilage degeneration, the hip loses its flexibility and strength, and may lead to the formation of bone spurs. Finally, as the condition worsens, the pain may be present all the time, even during non weight-bearing activities.
Unlike osteoarthritis, which is a "wear and tear" phenomenon, rheumatoid arthritis is a chronic inflammatory disease that results in joint pain, stiffness and swelling. The disease process leads to severe, and at times rapid, deterioration of multiple joints, resulting in severe pain and loss of function.
Although the exact cause of rheumatoid arthritis is unknown, some experts believe that a virus or bacteria may trigger the disease in people having a genetic predisposition to rheumatoid arthritis. Many doctors think rheumatoid arthritis is an autoimmune disease in which the synovial tissue of the joint is attacked by one's own immune system. The onset of rheumatoid arthritis occurs most frequently in middle age and is more common among women.
The primary symptoms of rheumatoid arthritis are similar to osteoarthritis and include pain, swelling and the loss of motion. In addition, other symptoms may include loss of appetite, fever, energy loss, anemia, and rheumatoid nodules (lumps of tissue under the skin). People suffering with rheumatoid arthritis commonly have periods of exacerbation or "flare ups" where multiple joints may be painful and stiff.
Developmental Dysplasia of the Hip
Developmental dysplasia of the hip (DDH), also called hip dysplasia, is a lifelong condition, shared by one in 1,000 people. Because DDH patients are born with an altered hip anatomy, the joint doesn't develop the normal wear patterns over the years. This leads to "wear and tear" arthritis at a relatively early age.
The most significant risk factor for DDH is a family history of the disorder. Women have a higher rate of DDH, as do first-born children and babies delivered breech.
Developmental dysplasia of the hip often can be diagnosed in the first year of life. Symptoms include diminished leg movement in the affected hip, shortening of the leg on the affected side, or asymmetry in leg positions. One or both hips may have DDH.
Avascular necrosis (AVN) of the hip results when poor blood circulation starves the bones that form the hip joint. In time, the starved bone dies, and the hip joint collapses.
AVN, sometimes called hip osteonecrosis, is most prevalent in younger or middle-aged adults.
Alcoholism and corticosteroids are by far the leading causes of AVN. In rarer cases, AVN can result from a blockage in blood vessels from sickle cell anemia or fat particles, or from dislocation of the hip due to trauma.
Hip pain, especially after standing or walking, is the most common symptom. Hip AVN most commonly afflicts the femoral head, where the femur (or thighbone) attaches to the pelvis (or hip bone). The femoral head may weaken and collapse.
Frequently Asked Questions
Since the BIRMINGHAM HIP Resurfacing implant is new in the United States, is it clinically proven?
While the BIRMINGHAM HIP Resurfacing implant is new to the United States, it is not a new implant or technique. It has been in use worldwide since 1997, and the US Food and Drug Administration reviewed a tremendous amount of resulting clinical data before approving it for use in this country.
Who is a candidate for the BIRMINGHAM HIP Resurfacing System?
The typical patient will be physically active, under 60 years of age, and suffering from hip arthritis, hip dysplasia or avascular necrosis of the hip. The implant can be used in patients over 60 whose bone quality is strong enough to support the implant. Your surgeon will make the determination if you are a candidate for hip resurfacing.
How long will the BIRMINGHAM HIP Resurfacing implant last?
It is impossible to say how long your implant will last because so many factors play into the lifespan of an implant. In the case of resurfacing, for instance, the metal-on-metal bearing surfaces of your new joint may extend its life longer than that of a traditional total hip replacement, but failure to comply with your physical rehabilitation regime may cause your implant to fail within months. A clinical study showed the BIRMINGHAM HIP Resurfacing implant had a survivorship of 98.4-percent at the five-year mark, which is comparable with the survivorship of a traditional total hip replacement in the under-60 age group.
How long will my scar be?
Your surgeon will use an incision of between six and eight inches in length. While some surgeons may use a slightly smaller incision, most will fall in that range.
What are my physical limitations after surgery?
Most surgeons will tell you that after the first year, you can return to whatever physical activity you enjoyed before hip pain limited your mobility. For instance, unlike total hip replacement, you will be able to return to jogging or singles tennis after your first year after surgery. During your first year, more conservative, low-impact activities like walking, swimming and bicycling are recommended for strengthening your femoral neck and the muscles around your resurfaced joint.