Infection used to be the complication surgeons who performed total hip arthroplasty feared the most. More effective prophylactic antibiotics have made the procedure much safer. Thromboembolic disease following hip surgery has been identified as today's number one problem; so much so that it is virtually impossible to find a surgeon who does not use some type of chemical prophylactic whenever he or she performs any major surgery around the hip joint.
Is the danger of thromboembolic disease as great as we have been led to believe? Is chemical prophylaxis the most effective way to prevent it? I doubt both premises. No one denies the fact that pulmonary emboli and/or thrombophlebitis can complicate major hip surgery but, in my opinion, their incidence has been greatly exaggerated. Interested pharmaceutical companies (the Pharmaceutical lobby) have unduly, and sometimes irresponsibly, promoted chemical prophylaxis as an indispensable adjuvant under all circumstances. In order to frighten the lay and medical community, data from experiences that took place four of five decades ago are presented. This is misleading, since in the early days of total hip replacements patients were kept in bed for several weeks following the surgical procedures. Today, they are mobilized either the first or second postoperative day, with obvious beneficial results. This factor has made a major difference.
I doubt the current popularity of prophylactic anticoagulants has had a positive influence in the incidence of thromboembolic disease. As far as I am concerned we have “made a mountain out of a mole” and have allowed industry to skillfully manipulate the issue.
Can I support my views on the issue? I think so. Doctor Lorraine Day, during her tenure as chief of orthopedics at the San Francisco General Hospital in the 1980's, allegedly reported on 1000 patients who underwent nailing of intertrochanteric fractures, and who did not receive chemical prophylactic of any kind. The incidence of thromboembolic disease she found was virtually nonexistent.
I was very intrigued by her report when I first heard it. It prompted me to look more carefully into the issue. Today, based on careful analysis of my own data and the review of the world literature, I am convinced that the problem, though a potential one, is being approached by most people without solid scientific support.
In the case of total hip arthroplasty, it is very likely that vascular damage, caused at the time of surgery, might eventually lead to the formation of clots and their possible dislodgment into the systemic circulation. This observation was first made by surgeons in New Zealand, whose names unfortunately I do not recall. Others in this country have repeated the New Zealanders' studies and some of them have claimed originality. The initial studies were performed using venography during surgery. It indicated that the femoral vessels experience severe kinking during extreme degrees of flexion and rotation of the hip. This kinking may be significant enough to injure the vessels. They also demonstrated that the degree of kinking was greater when the surgical procedure was performed through an anterior approach that calls for flexion and external rotation of the hip. The kinking was less when the posterior approach was used, which requires flexion and internal rotation. Our clinical experiences have supported this view, since the 4incidence of thromboembolic complications was higher when the anterior approach was used.
Since, I have virtually performed all of my total hip replacements through a posterior approach with the exception of the first one thousands, for which I used the anterior approach—I have adhered to an intraoperative protocol consisting of avoidance of extreme rotation and flexion of the hip and knee, and the frequent passive mobilization of the hip, knee and ankle during the surgical procedure. Since, it is necessary during surgery to hold the hip joint in flexion and internal rotation during the preparation of the femoral side, when the posterior approach is used, the length of time for such a position should be shortened as much as possible. There is no need to hold the knee in full flexion and internal rotation of the hip for more than the few minutes necessary to obtain the proper orientation.
I am also convinced that physical exercise is a most effective means of prophylaxis; better than any chemical or physical method. In my practice, I insist that patients begin active isometric and isotonic exercises of their gluteus maximus, the quadriceps and ankle and toes muscles as soon as possible. I also recommend deep breathing and trunk and abdominal exercises.
When I first visited Sir John Charnley's Hip Center in England in 1970, I heard him discuss the problem of thromboembolic disease in total hip surgery. At that time he kept his patients in bed for a very long time following surgery. He had tried various methods of prophylaxis with ambivalent results. At that particular time he was experimenting with ReoMacrodex. When I returned to the United States I used it in a large number of patients. I was disappointed by the high incidence of extensive swelling of the extremity that accompanied its use. I then proceeded to use aspirin as prophylaxis. For the last thirty-five years it has been my preferred chemical agent. The results have been satisfactory; however I suspect that it is not the aspirin that led to those results but the program of intraoperative and postoperative exercises.
Doctor AK Goswami, a former Fellow in our department in Los Angeles and now a surgeon in the United Kingdom, reviewed all my total hip arthroplasties and made some very interesting observations. For example, the incidence of fatal pulmonary embolism in nearly 1800 patients was 0.1%. There was no difference in results in relation to gender or age of the patients; the same was true for the type of stockings used, compressive elastic or intermittent compression devices. There was also no difference in the rate of complications between those patients who had the surgery performed on the East and West coasts of the United States. Epidural anesthesia, however, was associated with a lower incidence of complications as well as the posterior approach when compared with the lateral, transtrochanteric one.
The American literature is virtually empty of reports where no chemical prophylaxis was used. The British literature has seriously addressed the issue and some have claimed that prophylaxis is not needed. Some investigators have demonstrated, using controlled populations, that the incidence of thromboembolic disease was the same in patients receiving placebos and those receiving chemical prophylaxis. It is not likely that similar reports will be forthcoming from surgeons in the United States. The fear of litigation in the event of a fatality scares all of us. The power of the pharmaceutical industry is awesome. One method the pharmaceutical industry uses to enhance its power is the use of orthopedists to serve as peddlers of its products, who travel from city to city singing the praises of the respective medications. These peddler, needles to say, are in the direct or indirect payroll of the sponsoring firms. Their testimony against anyone who fails to administer the product they market is likely to bring about the guilty verdict of malpractice.
A pharmaceutical firm has offered between $800 and $1000 per patient to orthopedic surgeons willing to use low-molecular heparin and complete forms indicating demographic information and short post-surgical data. Recently, an internist in our hospital received $50,000 for the inclusion of 15 patients into the “study” being conducted by the industrial concern. Paying kickbacks to orthopedic surgeons for the use of marketing of surgical implants by industrial concerns has reached the degree that called for the Justice Department to officially investigate egregious abuses. The Justice Department refers the issue as being full of “serious transgressions and corruption.”
Obviously, aspirin in combination with exercise is not the only effective protocol against thromboembolic disease. Good results have been reported using other methods such as Coumadin. However, this method is complicated. The incidence of associated bleeding is relatively high and its use requires daily laboratory tests, which increase the cost of care. However, the cost is not nearly as high as it is with the use of low-molecular heparin (Lovenox). The hospital charge for the daily injections in the Miami area is over $100. The need to continue the daily injections (as recommended by the makers of the product) for either twenty or 5thirty days further raises the ultimate cost. Low-molecular heparin precludes the use of spinal and epidural anesthesia because of the reported danger of intraspinal bleeding. Instances of paraplegia secondary to the administration of heparin have appeared in the literature.
We have recently published our results in 1835 hip arthroplasties performed in 1585 patients where the prophylactic protocol consisted of intra and postoperative exercises followed by the rectal administration of 10 grains of aspirin immediately after surgery and 325 mg of the medication orally twice a day for the length hospitalization.
The surgical approach to the hip was a posterior one, and was carried out under general anesthesia in 459 instances, and regional anesthesia in 1376 instances. Graduated elastic stockings were used in 1117 instances and intermittent compression stockings in 718 instances. Passive exercises to the major joints of the operated extremity were carried out intra-operatively, and active exercises postoperatively. Fatal pulmonary embolism developed following 2 (0.10%) surgical procedures. Nonfatal pulmonary embolisms were diagnosed in 17 (0.9%) instances, and deep venous thrombosis in 18 (0.9%) instances.
These well-documented experiences strongly indicate that the simple and inexpensive method of prophylaxis is superior to more expensive methods that have associated complications, some of which serious.
A recent publication by Forward et al, conducted in Baltimore MD but published in the British edition of the Journal of Bone and Joint Surgeons, documented that aspirin and exercise render results superior to those with low-molecular heparin. This publication vindicates our work and that conducted by many others.
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