Medical Device Daily Associate

CHICAGO - As an increasing number of Americans continue to age, another large part of the population is faced with the growing problem of obesity; both of these conditions can adversely affect mobility and, ultimately, patients' independence.

At this, the 73rd edition of the American Academy of Orthopaedic Surgeons (AAOS; Rosemont, Illinois) annual meeting, studies were presented about how these two factors - aging and excess weight - impact patient outcomes after hip replacement, revision hip replacement and fracture-related surgical treatment. A series of research studies concluded that preoperatively, patients should undergo a full medical evaluation and physicians should optimize pre-existing conditions to ensure that the patient is in the best health possible prior to undergoing surgery.

Javad Parvizi, MD, associate professor of orthopedics at the Rothman Institute of Thomas Jefferson University (Philadelphia), reported that patients who had revisions of total hip arthroplasties in their 80s and 90s experienced a significant improvement in function and pain relief.

In his study, 158 patients over age 80 underwent revision total hip arthroplasty (THA). Within six months of surgery, he said 16.5% of patients experienced orthopedic complications and 15.3% incurred medical complications, which correlated with pre-existing medical conditions.

“Although revision surgery can be as rewarding and effective in the elderly as in younger patients,“ Parvizi said, “octogenarians are likely to experience higher complications.“

He said careful screening of these older patients will become a more important issue in the future, considering octogenarians - defined here as 85 years of age or older - are the most rapidly growing elderly age group. “In 1994, this group represented about 1% of the U.S. population, or about 3 million people. By 2050, it is estimated that there will be 19 million octogenarians, representing roughly 5% of the U.S. population.“

Parvizi said, “More and more, patients are outliving their prosthesis,“ adding that there has been a 79% increase in this statistic over the past decade and that 16.9% of such devices fail per year in patients over the age of 65.

The study indicated that a full medical evaluation of patients and an effort to bring them to optimum health levels prior to revision surgery are invaluable preoperative actions. Because fracture care requires immediate treatment, and thus does not allow time to optimize patient health, death rates are considerably higher in elderly patients with fractures. Diligent anesthetic care - including invasive cardiopulmonary monitoring during surgery - is also necessary to minimize complications, Parvizi said.

In another study of 1,434 elderly patients, Raymond Klug, MD, an orthopedic resident at University of Illinois Medical Center (Chicago), also found that the benefits of surgery outweighed the risks associated with non-operative treatment and limited mobility or immobility.

“After hip fracture surgery, patients had improved pain control and a faster return to walking and moving about freely,“ he said. “This, in turn, decreased the likelihood and severity of complications related to immobility such as bed sores, urinary tract infections, pneumonia and blood clots. Many of these complications can be life-threatening in elderly or debilitated adults.“

Klug noted that geriatric hip fractures are common injuries, with more than 300,000 reported in the U.S. alone every year. And, he added, that number would increase due to an ever increasing aging population.

He also said that geriatric hip fractures accounted for healthcare costs of about $8.7 billion in 1988, a number that is projected to nearly double by 2040 to $16 billion.

According to Klug, his research indicated orthopedic surgeons must first identify those factors related to sub-optimal outcomes in these patients. “Increasing age and a greater delay to surgery, as well as a higher ASA [American Society of Anesthesiologists] score - which measures a patient's general health, coexisting conditions, length of hospital stay and risk of death - can predict how much functional independence a patient may have after surgery.“

Another study involving 1,247 patients found that highly obese patients who underwent primary hip replacement were 2.3 times more likely to stay in the hospital more than five days and 2.6 times more likely to be discharged to a skilled nursing facility.

Thomas Turgeon, MD, assistant professor of orthopedic surgery at the University of Manitoba (Winnipeg), who presented the data, pointed out that with more than 50% of Americans being either overweight or obese, this study directly applies to many people.

“Obese patients may be able to avoid risk of complications and promote easier recovery if they consider weight loss before surgery and try to achieve a healthier lifestyle,“ he said.