Obesity increases incidence, severity, costs of knee dislocations

November 03, 2017

A new study of more than 19,000 knee dislocation cases in the U.S. between 2000 and 2012 provides a painful indication of how the nation's obesity epidemic is changing the risk, severity and cost of a traumatic injury.

"Obesity greatly increases the complications and costs of care," said lead author Dr. Joey Johnson, orthopedic trauma fellow at the Warren Alpert Medical School of Brown University and a physician at Rhode Island Hospital. "As the rate of obesity increases, the rate of knee dislocations increases. The total number of patients who are obese is increasing, so we are seeing more of these problems."

Addressing obesity, said co-author Dr. Christopher Born, a professor of orthopaedics at Brown, could therefore help reverse the trends in the data reported in the Journal of Orthopaedic Trauma.

Obesity's effects

Knee dislocations occur when the knee is badly disrupted because of multiple torn ligaments in the joint. Typically, this happens in vehicle crashes or contact sports like football. But Johnson and Born were inspired to look into the role of obesity because of what they've observed clinically over the last five years: an increase in knee dislocations among obese patients with an increased risk of vascular injury to the main artery that runs down the leg behind the knee.

Moreover, Johnson and Born have seen an increase in "low-energy" causes of dislocations, especially among obese patients. A few years ago, for example, Johnson saw a patient who experienced a knee dislocation after stepping off a ladder while hanging curtains.

To understand what's going on more comprehensively, they analyzed records in the Nationwide Inpatient Sample, a database of patients who've had hospital stays. Over the study period, they found that obese or morbidly obese patients made up an increasing share of knee dislocation patients, rising to 19 percent of patients in 2012 compared to just 8 percent in 2000.

Vascular injury is a particularly severe complication because if undiscovered and untreated, it can lead to amputation of the leg. The team's calculations from the data revealed that the odds of vascular injury during a knee dislocation were twice as high among obese or morbidly obese people than for normal-weight people.

Johnson said this finding is particularly insidious because a common clinical assumption is that vascular injury might be less likely among people suffering a low-energy knee dislocation. He and Born said the new research suggests physicians should be especially vigilant about vascular injury in obese knee dislocation patients, regardless of the cause.

"Orthopaedic and emergency medicine clinicians should have a heightened awareness for the potential of a knee dislocation in the obese patient following a low-energy fall," Born said. "That subset of obese patients who come in with complaints of knee pain need to be carefully evaluated so as not to miss a potentially catastrophic vascular injury."

The stakes, Johnson added, could be the leg itself.

"You don't want to be fooled," he said. "That patient could lose the leg, and their life could be changed forever."

In addition to increased incidence and the likelihood of vascular injury, the researchers looked at the costs of care. Patients with vascular injury, which was twice as likely among obese patients, stayed in the hospital for an average of 15.3 days, while patients without vascular injury stayed for an average of 7.4 days. In keeping with that difference, average hospitalization costs were $131,478 for vascular injury cases and $60,241 for those who avoided vascular damage.

"This study shows the power of using large databases to glean meaningful clinical and economic information that can significantly impact health care costs," Born said.

Though the data leave off in 2012, which is when Johnson began his residency, he said the trends are quite likely to have remained on track.

"Nothing would lead me to believe that the trend has been halted in any way," he said.
-end-
In addition to Johnson and Born, the paper's other authors are Justin Kleiner, Dr. Stephen Klinger, Dr. Philip McClure and Dr. Roman Hayda from the Department of Orthopaedic Surgery at Brown University and Rhode Island Hospital.

Brown University

Related Obesity Articles from Brightsurf:

11 years of data add to the evidence for using testosterone therapy to treat obesity, including as an alternative to obesity surgery
New research covering 11 years of data presented at this year's European and International Congress on Obesity (ECOICO 2020) show that, in obese men suffering from hypogonadism (low testosterone), treatment with testosterone injections lowers their weight and improves a wide range of other metabolic parameters.

Overlap between immunology of COVID-19 and obesity could explain the increased risk of death in people living with obesity, and also older patients
Data presented in a special COVID-19 session at the European and International Congress on Obesity (ECOICO 2020) suggests that there are overlaps between the immunological disturbances found in both COVID-19 disease and patients with obesity, which could explain the increased disease severity and mortality risk faced by obese patients, and also elderly patients, who are infected by the SARS-CoV-2 virus that causes COVID-19 disease.

New obesity guideline: Address root causes as foundation of obesity management
besity management should focus on outcomes that patients consider to be important, not weight loss alone, and include a holistic approach that addresses the root causes of obesity, according to a new clinical practice guideline published in CMAJ (Canadian Medical Association Journal) http://www.cmaj.ca/lookup/doi/10.1503/cmaj.191707.

Changing the debate around obesity
The UK's National Health Service (NHS) needs to do more to address the ingrained stigma and discrimination faced by people with obesity, says a leading health psychologist.

Study links longer exposure to obesity and earlier development of obesity to increased risk of type 2 diabetes
Cumulative exposure to obesity could be at least as important as actually being obese in terms of risk of developing type 2 diabetes (T2D), concludes new research published in Diabetologia (the journal of the European Association for the Study of Diabetes [EASD]).

How much do obesity and addictions overlap?
A large analysis of personality studies has found that people with obesity behave somewhat like people with addictions to alcohol or drugs.

Should obesity be recognized as a disease?
With obesity now affecting almost a third (29%) of the population in England, and expected to rise to 35% by 2030, should we now recognize it as a disease?

Is obesity associated with risk of pediatric MS?
A single-center study of 453 children in Germany with multiple sclerosis (MS) investigated the association of obesity with pediatric MS risk and with the response of first-line therapy in children with MS.

Women with obesity prior to conception are more likely to have children with obesity
A systematic review and meta-analysis identified significantly increased odds of child obesity when mothers have obesity before conception, according to a study published June 11, 2019 in the open-access journal PLOS Medicine by Nicola Heslehurst of Newcastle University in the UK, and colleagues.

Obesity medicine association announces major updates to its adult obesity algorithm
The Obesity Medicine Association (OMA) announced the immediate availability of the 2019 OMA Adult Obesity Algorithm, with new information for clinicians including the relationship between Obesity and Cardiovascular Disease, Diabetes Mellitus, Dyslipidemia, and Cancer; information on investigational Anti-Obesity Pharmacotherapy; treatments for Lipodystrophy; and Pharmacokinetics and Obesity.

Read More: Obesity News and Obesity Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.