Hip Replacement Surgery
Two years ago, a close friend of mine (I will refer to her as “D”) was experiencing a great deal of pain in her hip due to osteoarthritis. The cartilage in her hip had worn down to the point that she was in constant pain. Initially, D had pain when she walked, and it could be controlled by aspirin. Eventually, however, D could not walk without pain and over-the-counter medication did not offer relief. As the deterioration increased, she was in pain regardless of whether she was walking, sitting or lying down. She was prescribed Vicodin and Tylenol III, but neither offered much relief. In spite of the fact that she was young for such a procedure, her doctor scheduled her for total hip replacement surgery. This paper will discuss hip replacement surgery and its ramifications for patients.
According to The New England Journal of Medicine, women are far more likely to require joint replacement (in a weight-bearing joint), but far less likely to seek medical interventions. A study took place in Ontario, Canada in which nearly fifty thousand individuals over the age of fifty-five were surveyed about arthritis. Men and women were found to be equally willing to have surgery, but fewer women than men actually discussed the possibility with a doctor. Hawker’s conclusion was that “There is underuse of arthroplasty for severe arthritis in both sexes, but the degree of underuse is more than three times as great in women as in men.” (Hawker, et. al., 1022)
Causes leading to hip replacement surgery:
The most common reason a patient will require hip replacement surgery is the progression of osteoarthritis, though rheumatoid arthritis and aseptic necrosis are also causes. Osteoarthritis occurs when joint cartilage wears down. The only known treatments are weight loss and the avoidance of using that particular joint. Unfortunately for D, osteoarthritis runs in her family and hip replacement was the only option. The lack of pharmacological alternatives is the reason why osteoarthritis usually leads to joint replacement. Rheumatoid arthritis is a disease that causes joint swelling, pain and stiffness. It can be controlled with simple medications such as aspirin, and worse cases with prescription drugs. Eventually, joint replacement becomes an option. Finally, when the blood supply to an area of a bone diminishes, it can cause bone death. This is referred to as Aseptic necrosis and is the third potential reason for hip replacement surgery.
Only a surgeon can determine when it is time to consider surgery, but common life changes that lead to hip replacement are:
§ Pain that keeps the patient awake at night
§ Little or no relief from pain medications
§ Difficulty walking up or down stairs
§ Trouble standing from a seated position
§ Having to stop activities such as walking, because of the pain
(Hip replacement: relieve pain, improve mobility)
In the past, hip replacement surgery was only considered an option for people aged 60 and over, due to the fact that the prosthesis had a life span of 10 years and younger individuals could not be subjected to multiple hip replacements over the years without serious side effects (differences in leg length, for example). Today’s technology offers prosthetic hip joints which last much longer, extending the need for a replacement by fifteen to twenty years.
Because hip replacement surgery is considered an elective procedure (it is not life-threatening), patients are usually approved for the procedure when the pain from the hip is so great that they cannot function normally throughout their daily life.
Types of hip replacements:
In order to understand the types of hip replacements, one first must understand how the human hip works. In a normal hip, there is a ball at the top of the thighbone that fits into a rounded socket in the pelvis. Types of tissue called ligaments surround this area and provide support. Both the ball and the socket are covered with cartilage, which one could think of in the same way as brake pads on a car. It prevents the bones from rubbing together so that they move easily and do not cause pain. Another tissue covers the remaining surfaces in the hip joint, and makes a small amount of fluid that lubricates the hip and helps it to move easier.
In a hip with osteoarthritis, the cartilage that protects the ball and socket from rubbing together wears away. In rheumatoid arthritis, the remaining tissue stops making the lubricating fluid, and this causes pain, swelling, and stiffness. The aseptic necrosis means that some part of the bones, either in the ball or the socket, has begun to die due to blood loss.
A typical surgery will consist of a total hip replacement in which both the ball and socket are replaced with artificial materials. The ball is usually a metal or ceramic material, and the socket can be made of metal, ceramic or plastic with a metal covering. A relatively new advancement is the use of a titanium ball and socket, which was the type of hip replacement that D received.
In addition to the prosthesis, there is also a cemented or non-cemented option. The cemented option means that a special type of medical cement is used to fill the gap between the prosthesis and the remaining natural bone. Younger patients are often treated with the non-cemented option, which means that the remaining bone is covered with a bone-like substance. This will allow bone to grow around and over the prosthesis. D was told that the bone growth would eventually mean that she would no longer set off metal detectors, but two years after surgery that has not happened.
The surgery itself:
Patients are usually asked to take many precautions before surgery. The first is to attend a class in which the hip replacement patients learn about the surgery itself and how to care for themselves afterwards. Patients have extreme limitations after surgery, usually for the first three months, and they are given explanations as to those limitations and to preparations they should make. Patients are not permitted to bend over, as they cannot have their thigh closer than a ninety-degree angle to the torso. In D’s class, she was given an opportunity to purchase a kit that included a long-handled shoe horn, a device to put on her socks, a “grabber” so she could pick up objects from the floor without bending over, and a long-handled sponge for use in the shower. She was given a complimentary pill sorter in order to keep track of painkillers, anti-inflammatory medications and other prescriptions after the surgery.
Patients who have enough time should donate blood before the surgery. If they experience significant blood loss, it can be replaced with their own blood rather than a donation from a stranger. In addition, patients should see the dentist in order to eliminate any infections. Such an infection can enter the bloodstream and compromise the prosthesis. Some patients may be asked to lose weight before the surgery, due to the fact that the hip is a weight-bearing joint and the prosthesis may not last as long if the patient is significantly overweight.
The most important facet of planning is that of social planning. Due to the restrictions placed on the patient after the surgery, the patient will need to have a caretaker, at least for the first couple of weeks. This caretaker should be capable of going shopping, preparing meals, assisting with getting in and out of bed and getting dressed, bathing and assistance with putting on and removing the pressure stockings. Older patients may consider a stay at a long-term care facility while other patients who live alone will want to have a caretaker (often a friend or family member) who can perform the necessary duties until he or she is able.
In anticipation of a great deal of down time, patients are prescribed a blood thinner that they must begin taking a week or two before surgery. The reason for this is that the immobilization following surgery can lead to deep-vein thrombosis (more commonly referred to as a stroke). The use of a blood thinner reduces these risks. A 2004 study found that out of 183 patients, 35 developed this complication when given a placebo, compared to 17 who took a blood thinner during immobilization (Lassen, M., 729). Often they are prescribed Heparin, Warfarin or Cumadin and warned that a simple cut or scratch could lead to severe bleeding. Patients are advised to be especially careful once this prescription has begun. Within a week of the surgery date, patients come in to the hospital for a pre-op appointment in which they give blood for lab tests, submit to a series of x-rays, an echocardiogram, and receive their prescription blood thinner.
Patients are usually admitted the day of the surgery. D was admitted at 6:00am in order to be ready for a 10:00am surgery. She was advised not to eat for 12 hours before the surgery and not to drink anything the day of the surgery. She was brought to a staging area where she changed into a gown and a surgical nurse started an IV. Three different nurses asked her a series of the same questions regarding possible infections, if she had eaten that day, and other necessary information in order to proceed with the surgery safely. The part she found most amusing was when the nurse handed her a marker and asked her to mark the hip on which the surgeon would be operating, a precaution used to prevent having surgery on the wrong limb.
When she was ready to be transferred to the operating room, she was given a heavy tranquilizer through her IV. She was disoriented by the time she reached the operating room, and barely remembers being lifted to a seating position and having a spinal block, or epidural. This is performed in order to avoid the potential risks and side effects that accompany general anesthesia. While she was never completely unconscious, she remembers nothing about the surgery.
The surgery took two hours, after which she was transferred to the recovery room. While in surgery, she was outfitted with pressure stockings, which covered her legs from her feet up to her thighs. The wound was closed with staples, fitted with plastic tubing that functioned as a drain, and covered with bandages. A catheter was inserted due to the fact that she would not be able to move or walk for at least twenty-four hours. A V-shaped pillow was placed between her legs and secured with Velcro straps. Finally, inflatable pulse devices were attached to her feet in order to keep the blood circulating while she was prone in bed. Directly from surgery, she was transferred to a special bed that had a handle attached to a chain, so that she could use it to lift herself up when necessary.
D spent an hour in the recovery room before being moved to a private room. D spent two full days in the hospital and was released on the third day. There is always the risk of complications with surgery. The risks associated with hip replacement surgery are:
Ø Blood clots (managed by the blood thinner and stockings)
Ø Heart attack or stroke
Ø Nausea in the days after the surgery
Due to unexpected complications during surgery (a sciatic nerve that was in the wrong place, obstructing access to the hip), D had to have a blood transfusion and was unable to start walking until the second day after her surgery. Under normal circumstances, patients wait one day before a physical therapist comes to the room to help them get up and walk around with the aid of a walker. Once the patient is able to walk, the pulse devices on the feet are removed. As is typical in hip replacement surgery on a healthy patient, D was released on the second day after the surgery.
The first few days were difficult, as D was in a great deal of pain and could not sit down, stand up, or lay down without assistance. Her toilet seat had been replaced with a raised medical toilet seat (which she still prefers today), and this was the only area in which she did not require help. She had to sit on pillows in order to keep her thigh at the correct angle to her torso. A physical therapist visited her at home every other day for the first week. The therapist took D through a series of simple but painful exercises in order to strengthen the area and prevent blood clots. She was advised to get up and move as much as possible.
The staples were removed in her home by the physical therapist two weeks after surgery. Their removal made it possible for D to take a shower, though she had to keep bandages on the area for an additional two weeks. D was given iron in order to promote tissue healing and to restore muscle strength. Once she was able to walk around regularly, she was able to stop wearing the pressure stockings and she no longer had to take the blood thinner.
The total recovery time for hip replacement surgery is three months. During this time, the patient must submit to the restrictions placed upon them by the surgeon. In addition to keeping the angle of the leg larger than ninety degrees, the patient may not cross his or her legs, turn the feet excessively, and the patient must sleep with a pillow between the legs until advised that this is no longer necessary. The patient can expect to see the surgeon every few weeks in order to have the wound checked, to x-ray the new hip, and ensure that there are no dangerous side effects. A young patient or a patient who was active before the surgery can expect a much shorter recovery time. D was back at work within three weeks and replaced the walker with a cane during that month. Within six weeks, D no longer needed a cane.
Patients who have hip replacement surgery must be on the lookout for signs of infection. According to Dr. Werner Zimmerli, “Infections associated with prosthetic joints cause significant morbidity and account for a substantial proportion of health care expenditures.”
Possible signs that the joint area has become infected are:
Persistent fever (higher than 100 degrees orally)
Increasing redness, tenderness or swelling of the hip wound
Drainage from the hip wound
Increasing hip pain with both activity and rest
A patient who experiences any of these symptoms should see a doctor immediately.
For the rest of her life, D will need to take a course of antibiotics before having dental work, due to the possibility of bacteria entering the bloodstream and attacking the prosthesis. She must stay active, watch her weight, and avoid falls at all costs. She will also need to:
Participate in a regular light exercise program to maintain proper strength and mobility of the new hip.
Take special precautions to avoid falls and injuries. Individuals who have undergone hip replacement surgery and suffer a fracture may require more surgery.
Notify the dentist that the patient has had a hip replacement. One will need to take antibiotics before any dental procedure for a minimum of two years after the surgery and possibly longer, depending on past health history.
See an orthopaedic surgeon periodically for routine follow-up examinations and X-rays, even if the hip replacement seems to be doing fine.
Total hip-replacement surgery is a good option for those who have arthritis or necrosis of the bone; often, it is the only option that will allow the patient to resume a normal life. One must keep in mind that some designs will wear out after a number of years; D was informed that the titanium hip prosthesis should last the rest of her life. A similar type of long-lasting replacement is the amorphous diamond coating. According to Seppo Santavirta:
Amorphous diamond was found to be biologically inert, and simulator testing indicated excellent wear properties for conventional total hip prostheses, in which either the ball or both bearing surfaces were coated with hydrogen-free tetrahedral amorphous diamond films. Simulator testing with such total hip prostheses showed no measurable wear or detectable delamination after 15,000,000 test cycles corresponding to 15 years of clinical use. The present work clearly shows that wear is one of the basic problems with totally replaced hips. Diamond coating of the bearing surfaces appears to be an attractive solution to improve longevity of the totally replaced hip.
When Santavirta refers to “excellent wear properties”, he is referring to the amount of time it takes to wear out a hip prosthesis. In the case of the diamond-coated prosthesis, it appears that it will not wear out for at least fifteen years. This test is accomplished by using a device that simulates activity. A human, of course, would not move constantly for fifteen years, so the time limit is approximate. In any case, there are advancements being made in hip replacement technology that will allow recipients full use of their new hip for many years to come.
Hawker, M.D., G., et. al. (2000).Differences between men and women in the rate of Use of hip and knee arthroplasty. The New England Journal Of Medicine. 342, 1016-1022.
(2007 Apr 18). Hip replacement: relieve pain, improve mobility. Retrieved April 24, 2007, from MayoClinic.com Web site: http://www.mayoclinic.com/health/hip-replacement/AR00028
Interview with former patient Dorothy Moody. April 24, 2007.
Lassen, M. (2002).Use of the Low-molecular-weight heparin reviparin to prevent deep-vein thrombosis after Leg Injury Requiring Immobilization. New England Journal of Medicine. 347, 726-730.
Santavirta, S. (2003).Compatibility of the totally replaced hip. Acta Orthopaedica. 74, 1-19.
Shiel, Jr., W.C. (2007 Apr 11). Total hip replacement. Retrieved April 24, 2007, from MedicineNet.com Web site: http://www.medicinenet.com/total_hip_replacement/article.htm
Zimmerli, W. (2004).Prosthetic-joint infections. The New England Journal of Medicine. 341, 1645-1654.