A reality for orthopedic surgeons today is that more and more of the patients they consult are obese. In the United States, 32% of men and 36% of women are obese, with the obesity scale ranging from a bone mineral density (BMI) > 30 a BMI greater than 50 (super-obese).
According to Flegal et al. in “Prevalence of obesity and trend in the distribution of body mass index among US adults, 1999-2010” published on February 1, 2012 in the Journal of the American Medical Association, one-third of people in the United States are obese.
And, unfortunately, the obesity epidemic continues to grow. Its prevalence in the last 25 years has doubled. In 1985, no state had more than 15% obesity, while in 2015 no state had less than 20% obesity.
What to Do With Obese Surgical Candidates?
Tyler D. Goldberg, M.D., an affiliate assistant professor at the University of Texas, Dell Medical School in the department of surgery and perioperative care, and an orthopedic surgeon with Texas Orthopedics in Austin, Texas, knows that deciding on whether to operate on an obese person can be tricky for a surgeon and that pre-operative planning is essential for determining best patient outcomes.
He recently discussed the challenges an obese patient presents when it comes to direct anterior approach total hip arthroplasty (THA) and how the benefits and risks of doing the surgery have to be carefully weighed.
Goldberg said first, you have to recognize the difficult patients. During the pre-operative stage, you need to be able to identify both ideal and difficult patients. Besides obesity, hip type, previous hardware and deformities could also put a wrench into the situation, so it is important to recognize all these challenges right from the beginning, so you make an informed decision.
He also said that you need to be honest about knowing your own limits. Can you do this surgery safely and accurately utilizing the direct anterior approach?
When it comes to surgery logistics, Goldberg said the most difficult patients early in the learning curve for the direct anterior approach are those with a muscular, short, varus hip; obesity and big tensor fasciae latae (TFL).
During the preoperative evaluation, he recommends that you identify these patient characteristics to properly determine which will be ideal candidates and which will be difficult patients.
According to Goldberg an ideal candidate for the direct anterior approach early in the surgeon’s learning curve is a thin, valgus female with soft, pliable muscles and no other pathology, while a difficult patient is an obese patient who has a short varus neck and may have protrusion (ankyloses), severe deformities and/or hardware from previous surgeries.
He said that it is best to avoid the difficult patients early in your learning curve, pointing to studies that show higher complication and infection rates in obese patients.
In one study he referenced, “Complication Rates After Hip or Knee Arthroplasty in Morbidly Obese Patients,” the authors reviewed 12,355 patients, comparing those with a BMI greater than 40 to those with a BMI less than 40. They found no change in venous thromboembolism or bleeding, but an increase in erythema, peripheral edema, diarrhea and gastrointestinal or abdominal pain, wound inflammation or infection and respiratory tract or lung infections.
Other studies have shown a higher use of OR time, anesthesia induction and surgery time as well as a higher risk of infection during primary THA the more obese a patient is.
