Hip surgery in the elderly and obese, orthopaedic research emphasizes need for complete preoperative assessments

Mar 23 2006

As many Americans continue to grow older, another large part of the population is faced with the growing problem of obesity: both of these conditions can adversely impact mobility and ultimately, patients' independence.

At the 73rd Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS) studies were presented about how these two factors -- aging and excess weight -- impact patient outcome 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 the patient is in the best health possible prior to undergoing surgery.

Javad Parvizi, MD, FRCS, associate professor of orthopaedics at the Rothman Institute, Thomas Jefferson University in Philadelphia, found that patients in their 80s and 90s who had revisions of total hip arthroplasties (joint replacements) experienced significant improvement in function and pain relief. In his study, 158 patients over the age of 80 underwent revision total hip arthroplasty. Within six months of surgery, 16.5 percent of patients experienced orthopaedic complications and 15.3 percent 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," said Dr. Parvizi. "Octogenarians are likely to experience higher complications."

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, complications and 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.

"Revision surgery does offer improvements in quality of life, decreased pain, and enhanced mobility so that these elderly patients can remain independent," added Dr. Parvizi.

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

"After hip fracture surgery, patients had improved pain control and a faster return to walking and moving about freely," explained Dr. Klug. "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 individuals."

According to Dr. Klug, his research indicated that orthopaedic surgeons must first identify those factors related to poor outcomes in these patients. "Increasing age and a greater delay to surgery, as well as a higher American Society of Anesthesiologists (ASA) 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."

"What was once considered a purely orthopaedic problem is more related to patients' underlying medical condition than any specific injury pattern," added Dr. Klug. In other words, while the surgeon's role is relatively straightforward and short-lived, the patient's general state of health and medical co-morbidities are what may predict a poor outcome post-surgery.

Thomas Turgeon, MD, assistant professor of orthopaedic surgery at the University of Manitoba, Canada, presented a study of 1,247 patients of varying weight who underwent primary hip replacement. He and his research team found highly obese patients 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 (SNF).

A formula and recommendations from the Centers for Disease Control and Prevention describe body mass index (BMI) ranges. People with a BMI below 18.5 are considered underweight; 18.5-24.9 are normal; 25-29.9 are overweight; and more than 30 are obese. At one year, patients who were overweight and obese (BMI's in excess of 25) had an average decrease in scores for functionality and pain compared to patients with normal body mass, although this finding was not clinically significant.

With more than 50 percent 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," Dr. Turgeon explained.

Studies by Dr. Klug and Dr. Turgeon did not receive outside funding. Some members of Dr. Parvizi's research team are consultants to orthopaedic industry, including Stryker.

An orthopaedic surgeon is a physician with extensive training in the diagnosis and non-surgical as well as surgical treatment of the musculoskeletal system, including bones, joints, ligaments, tendons, muscles and nerves.