Door to Neurological Development

A year-and-a-half after the U.S. Food and Drug Administration notified healthcare professionals about tendon dangers posed by certain antibiotics, few physical therapists are aware of the issue. At the time of the warning, the FDA also required manufacturers of systemic fluoroquinolone antimicrobial drugs to include a boxed warning on product labeling about the association between these medications and the increased risk of tendinitis and tendon rupture.

Fluoroquinolones are FDA approved for the treatment or prevention of certain bacterial infections. The medications involved in the FDA’s action are: Cipro and generic ciprofloxacin, Cipro XR and ProQuin XR (ciprofloxacin extended release), Factive (gemifloxacin), Levaquin (levofloxacin), Avelox (moxifloxacin), Noroxin (norfloxacin), and Floxin and generic ofloxacin.

Some at Higher Risk
Tendinitis and tendon rupture can occur at any age, including in young, active adults, with fluoroquinolone use. The risk, however, is further increased in those older than age 60; in kidney, heart and lung transplant recipients; and with use of concomitant steroid therapy, FDA spokeswoman Crystal Rice says.

Tendinitis and tendon rupture most frequently involve the Achilles tendon, and rupture of the Achilles tendon may require surgical repair. Tendinitis and tendon rupture in the rotator cuff, the hand, the bicep and the thumb also have been reported. Tendon rupture can occur during or after completion of fluoroquinolones, and cases have been known to occur up to several months after completion of therapy, Rice says.

“Specifically, Achilles tendon rupture with fluoroquinolone usage was determined to occur at a three to four times higher rate in comparison to patients who did not receive fluoroquinolones, based on literature review. But this relative risk is expected to be higher among patients older than 60 years of age, in those taking corticosteroids, and among transplant patients,” Rice says. “It has to be noted that when looking at these rates, the population background rates for tendon rupture should be accounted for and, therefore, it would be very hard to estimate a risk for any given patient.”

Why this occurs is not yet clear. “The question is, is it a direct effect of the drugs? People seem to be leaning toward that it is a direct effect because it can occur hours after an initial dose,” says Charles Ciccone, PT, PhD, FAPTA.

Ciccone, who teaches PT at Ithaca (N.Y.) College, says tendon injuries among those taking fluoroquinolones will be hard to avoid until researchers figure out what is behind the susceptibility and clinicians can screen for it.

Identifying the Injury
Patients should, at the first sign of tendon pain, swelling or inflammation, stop taking the fluoroquinolone, avoid exercise and use of the affected areas, and promptly contact their doctors about changing to a non-fluoroquinolone antimicrobial drug, Rice says.

PTs might be more likely to be the first providers to encounter these patients in areas that have direct access.

“Physical therapists need to be aware of the increased risk of tendinitis and tendon rupture in patients that are taking fluoroquinolones,” says James Irrgang, PT, PhD, ATC, FAPTA, president of the American Physical Therapy Association’s Orthopaedic Section.

“This should include questioning patients with complaints of tendon injury about whether they are currently taking fluoroquinolones or have taken them in the past,” Irrgang says.

Brenda L. Greene, PT, PhD, whose case report on a patient with bilateral Achilles tendinopathy secondary to fluoroquinolone antibiotic use was published in the journal Physical Therapy, December 2002, says, “The problem is that ... I don’t know of any tests that can make the definitive statement that these symptoms are due to fluoroquinolone side effects. So the PT has to figure out whether the patient presents differently than someone with the typical overuse injury.”

“If it appears related to the medication, then you have to treat it differently. I think the difference is that it is a biomechanical breakdown of some sort in the tendons; so, we have to think about protecting the tendon being the first phase and loading being the next phase,” Greene says.

Ciccone recommends putting these patients on crutches until they can see their doctors. “Definitely don’t exercise it, touch it or look at it cross-eyed. Put the person in a non-weight-bearing situation as soon as possible,” he says.

Greene, an assistant professor, division of physical therapy, department of rehabilitation medicine, Emory University, Atlanta, says that recovery from tendon-related symptoms due to fluoroquinolone use does not seem to be linear, as it is with most musculoskeletal injuries.

“These injuries don’t slowly get better and better with PT, like we often see with musculoskeletal injuries. With this disease process, there seems to be an extra long non-weight-bearing or protective period needed. But once the tendon reaches a certain threshold, then it seems to exponentially get better,” Greene says. •
Lisette Hilton is a freelance writer.
By Lisette Hilton
Monday May 10, 2010
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