Need another reason to keep your weight under control?
Excess weight can cause dislocation of your knee and may even lead to a complication that results in amputation of your leg.
A new study attributes a surge in dislocated knees to the U.S. obesity epidemic.
“Obesity greatly increases the complications and costs of care,” said study lead author Dr. Joey Johnson, an orthopedic trauma fellow at Brown University’s Warren Alpert Medical School.
“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,” Johnson explained.
Knee dislocations result from multiple torn ligaments. Vehicle crashes or contact sports, such as football, are common causes.
For the study, the researchers analyzed more than 19,000 knee dislocations nationwide between 2000 and 2012. Over that time, people who were obese or severely obese represented a growing share of knee dislocation patients — 19 percent in 2012, up from 8 percent in 2000.
Obesity is also linked to more severe knee dislocations, longer hospital stays and higher treatment costs, according to the study published recently in the Journal of Orthopaedic Trauma.
And the chances that a knee dislocation would also injure the main artery behind the joint and down the leg were twice as high for obese patients than for those whose weight was normal, the findings showed. This severe complication of knee dislocation — known as a vascular injury — can lead to leg amputation if not treated, the study authors said.
Patients with a vascular injury averaged 15 days in the hospital, compared with about one week for other patients. Their average hospitalization costs were just over $131,000 and $60,000, respectively.
The study authors said doctors should be especially watchful for vascular injury in obese patients whose knees are dislocated.
“That subset of obese patients who come in with complaint of knee pain need to be carefully evaluated so as not to miss a potentially catastrophic vascular injury,” said study co-author Dr. Christopher Born, a professor of orthopedics at Brown.
Reducing obesity rates could help reverse the growing number of knee dislocations, the researchers suggested.
The U.S. National Institute of Arthritis and Musculoskeletal and Skin Diseases has more on knee problems.
SOURCE: Brown University, news release, Nov. 3, 2017
Athletes in high impact sports or sports that require a lot of running and jumping are prone to knee injuries. kneecap dislocations most often happen as a result of trauma, such as when a football player is tackled, or a soccer players falls hard on his knees.
The kneecap, or patella, is referred to as dislocated when it slips out of the groove in the femur (thigh bone) that is naturally sits in. Some patients recover from a dislocation and never experience the condition again. For other patients, however, the patella will chronically dislocate until it is repaired through surgery.
You’ll know you’ve dislocated your knee cap if you feel these symptoms following an incident:
- Severe pain at the knee
- Redness and swelling
- Difficulty moving the knee at all
While many patients can overcome a patellar dislocation with a physical therapy regimen, severe cases will require surgery.
If the surrounding cartilage and bone are not severely damaged, five to six weeks of rehabilitation should be sufficient. This includes strengthening exercises designed to rebuild the muscles surrounding the patella, which also will in-turn restore the range of motion that should be enough to recover from the injury.
If surgery is required, an orthopedic knee specialist will reset the kneecap and perform a short arthroscopic procedure to remove any dislodged pieces of bone, and smooth down any damaged cartilage. As with most sports injuries, surgery will also require 6 to 8 weeks of rehabilitation for proper healing.
Dr. Main and Dr. Pick-Jacobs treat athletes with mild to severe patella issues routinely. Dr. Main is an expert in arthroscopic surgery to repair the knee following even the most severe cases of kneecap dislocation.
Knees that “pop,” “click” or “crackle” may sometimes be headed toward arthritis in the near future, a new study suggests.
It’s common for the knees to get a little noisy on occasion, and hearing a “crack” during your yoga class is probably not something to worry about, experts say.
But in the new study, middle-aged and older adults who said their knees often crackled were more likely to develop arthritis symptoms in the next year.
Of those who complained their knees were “always” noisy, 11 percent developed knee arthritis symptoms within a year. That compared with 4.5 percent of people who said their knees “never” popped or cracked.
Everyone else fell into the middle. Of people who said their knees “sometimes” or “often” made noise, roughly 8 percent developed knee arthritis symptoms in the next year.
Doctors have a term for those joint noises: crepitus.
Patients commonly complain of it, said Dr. Grace Lo, the lead researcher on the study. She’s an assistant professor at Baylor College of Medicine in Houston.
But until now, it hasn’t been clear whether crepitus can predict symptomatic knee arthritis. That means people not only have evidence of cartilage breakdown on X-rays, but also suffer symptoms from it — namely, frequent pain and stiffness.
“Our study suggests crepitus is not completely benign,” Lo said. “It’s a sign that something is going on in the knee joint.”
Dr. Joseph Bosco, an orthopedic surgeon who wasn’t involved in the study, agreed that frequent crepitus should be checked out.
“A lot of people’s knees ‘snap’ and ‘pop,'” said Bosco, a professor at NYU Langone Medical Center in New York City. “Do they need to run out for knee replacements? No.”
But, he added, “if you experience crepitus regularly, get an evaluation.”
The findings, published May 4 in the journal Arthritis Care & Research, come with some caveats.
The nearly 3,500 study participants were at increased risk of developing knee arthritis symptoms to begin with, Lo explained.
The participants ranged in age from 45 to 79. Some were at risk of knee arthritis simply because of old age, while others had risk factors such as obesity or a history of a significant knee injury.
So it’s not clear, Lo said, whether the findings would translate to — for example — a 35-year-old whose knees crack when she runs.
Plus, even though the study participants were initially free of knee arthritis symptoms, some did have signs of arthritis damage on an X-ray.
And it was in that group where crepitus was a red flag: People who “often” or “always” had noisy knees were nearly three times more likely to develop knee arthritis symptoms as those who “never” had crepitus.
According to Lo, the findings could be useful in everyday medical practice. “If patients are complaining of frequent cracking or popping in the knees,” she said, “get an X-ray.”
If that turns up signs of arthritic damage, Lo said, then the risk of progressing to symptoms in the near future is probably significant.
Unfortunately, there is no magic pill that can stop arthritis in progress. But, Lo said, for patients who are heavy, weight loss can help.
Some, she added, might benefit from strengthening the muscles that support the knees.