High failure rate seen after some ACL repairs

NEW YORK (Reuters Health) — Anterior cruciate ligament (ACL) reconstruction using a replacement ligament from a cadaver has a high failure rate in young, active adults, according to a study reported at the American Orthopedic Society for Sports Medicine conference in Orlando, Florida.

The ACL is a key ligament inside the knee that helps keep it stable. Located in the center of the knee joint, it runs from the thigh bone to the shin bone through the center of the knee.

Typically, tearing the ACL occurs with a sudden direction change. To repair a torn ACL, a surgeon replaces the damaged ligament with a new one, either from a cadaver or the patient's own body.

Among 64 patients younger than age 40 with high activity levels who had ACL reconstruction with a cadaver replacement ligament and were followed for a minimum of two years, the grafted ligament failed in 15 (23.4 percent).

Graft failure was defined as need for repeat ACL reconstruction due to injury or graft failure or poor scores on a combination of orthopaedic outcome measures.

"This failure rate in this young, active population is exceedingly high when compared to a previous study that looked at failure rates of cadaver replacement ligament in patients older than 40," Dr. Gene Barrett of the Mississippi Sports Medicine and Orthopedic Center in Jackson, who was involved in the study, said in a statement.

"While there are obvious benefits of using the cadaver ligament, like avoiding a second surgical site on the patient, a quicker return to work and less postoperative pain, for the young patient who is very active, it may not be the right choice," Barrett added.

"In no way are we saying that (cadaver) grafts should not be used anymore," Dr. Kurre Luber, who presented the study findings in Orlando, said in interview with Reuters Health.

"We are just suggesting that maybe (doctors) should reconsider or use caution when putting a (cadaver replacement ligament) in a young active patient because our data certainly suggests that they are more likely to fail."

An estimated 80,000 ACL tears occur each year in the US, including recently to famed pro golfer Tiger Woods.

Repeat TB test urged for overseas adoptions

NEW YORK (Reuters Health) — Children adopted from overseas may harbour tuberculosis infection even if they test negative for TB upon arriving on US soil, a new report warns.

"It's important to get that repeat tuberculosis skin test done so you don't miss those children with TB infection that could go on to develop disease," Dr. Mary Allen Staat of the Cincinnati Children's Hospital Medical Center told Reuters Health.

People with latent (dormant) TB infection, she explained, are not sick and are not contagious, and treatment with a nine-month course of isoniazid will usually clear the infection. But once infection progresses to active disease, a person may become ill and can spread the disease to others. At this point, treatment is much more complex, requiring as many as four drugs.

The American Academy of Pediatrics recommends that all children adopted from countries where TB is endemic be tested soon after they arrive in the US, and suggests that children who test negative be retested later on if they are malnourished, Staat and her team point out in an article in Pediatrics this month.

However, they also point out that no specific evidence justifying this recommendation has been published.

To investigate whether repeat testing would spot more children with TB infection, the researchers looked at 527 internationally adopted children treated at their International Adoption Center.

Twenty-one percent tested positive for latent TB infection. The researchers were able to perform repeat tests in just under half of the 191 children who had tested negative initially, and 20 percent of these children tested positive upon retesting.

There are many reasons why a child might test negative for TB initially, Staat said.

Some children may be too malnourished to mount an appropriate immune response to the test, while others may have been infected shortly before leaving their country of origin.

It can take two to 12 weeks after being exposed to TB for a person to test positive for infection.

Heartbeat irregularity appears benign

NEW YORK (Reuters Health) — A new study offers more evidence that the rapid heartbeat seen in many hard-training athletes is typically a benign side effect of physical conditioning.

Elite athletes usually have lower-than-normal heart rates when at rest, but when they are active, some develop rapid heart rhythms known as ventricular tachyarrhythmias. Studies suggest that up to 30 percent of high-level athletes show irregular ventricular rhythms.

In the absence of any underlying heart abnormality, these rhythm irregularities are thought to stem from the effects of training and are considered to be a part of a benign condition known as "athlete's heart."

Another feature of athlete's heart is an enlargement of the heart's main pumping chamber, known as left ventricular hypertrophy, or LVH.

In non-athletes, pathological LVH usually increases the risk of ventricular tachyarrhythmias as it worsens. So in the current study, Italian researchers looked at whether there is a similar relationship in elite athletes.

The researchers outfitted 175 Olympic and world-class athletes with portable monitors that recorded their heart's electrical activity over 24 hours. They also had them undergo ultrasound scans to detect LVH.

Overall, the researchers found, 14 percent of the study group had evidence of LVH. But there was no indication that LVH raised the risk of ventricular tachyarrhythmias, the researchers report in the American Journal of Cardiology.

The findings suggest that, in contrast to pathological cases, the ventricular arrhythmias seen in elite athletes are not caused by LVH-induced changes in the heart's electrical activity, according to the researchers, led by Dr. Alessandro Biffi, of the Italian Olympic Committee in Rome.

Instead, they say, alterations in nervous system activity, brought on by high-level athletic training, may be responsible. In support of this, past research has shown that ventricular tachyarrhythmias decline once athletes stop training and playing at a competitive level.

These latest findings, Biffi and colleagues write, "offer a measure of clinical reassurance regarding the benign nature of ventricular tachyarrhythmias in elite athletes and the expression of athlete's heart."

ED from prostate cancer therapy treatable

NEW YORK (Reuters Health) — A new study shows that a substantial minority of men receiving so-called androgen deprivation therapy, or ADT, for prostate cancer experience erectile dysfunction (ED). However, many respond well to ED therapy, doctors from Memphis have found.

Men with advanced prostate cancer may be given ADT to stop their production of testosterone, which may drive tumour growth.

ED is "grossly underreported" by men treated with ADT, Dr. Ithaar H. Derweesh told Reuters Health.

Moreover, "studies that have been reported in the literature have tended to focus on decreased libido (sex drive) and have not examined the issue of erectile dysfunction per se."

Given that there is a lack of information on the prevalence of ED and the response to its treatment in patients receiving ADT, Derweesh and colleagues at the University of Tennessee Health Science Center studied 395 men treated with ADT at their institution over a period of about 15 years.

The average age of the men was 71.7 years and the men were followed for more than seven years.

During that time, 14.4 percent of men reported ED, they report, and 70 percent of these men had "new-onset" ED.

According to Derweesh and colleagues, 47 percent of men with ED responded successfully to ED treatment, most often with drugs such as Viagra.

"We demonstrate for the first time in a large series," Derweesh noted, that these types of drugs are effective in the treatment of ED caused by androgen deprivation therapy.

Vision vitamins may be harmful for smokers

NEW YORK (Reuters Health) — Based on new research, smokers may want to check the beta-carotene content of any multivitamin supplements they are taking, especially if these supplements are promoted as being beneficial for eye health.

There's strong evidence that high dose beta-carotene can boost smokers' lung cancer risk, but many multivitamins that contain large amounts of the nutrient carry no warning, Drs. Tawee Tanvetyanon and Gerold Bepler of the H. Lee Moffitt Cancer Center and Research Institute at the University of South Florida in Tampa report in the journal Cancer.

"We need to make the public more aware of this problem," Tanvetyanon told Reuters Health.

Tanvetyanon and Bepler reviewed all studies of high-dose beta-carotene supplementation and lung cancer risk in the medical literature, and also evaluated the amount of beta-carotene found in dozens of supplements.

Their pooled analysis showed that smokers who took high-dose beta-carotene (from 20 to 30 milligrams daily) had a 24 percent increased risk of lung cancer compared to smokers who weren't taking beta-carotene. However, the nutrient didn't affect lung cancer risk for ex-smokers.

Body changes plague women with RA

NEW YORK (Reuters Health) — Women with rheumatoid arthritis (RA) are more likely to have abnormal body fat distribution, especially those with a normal weight, compared with men with RA or women without the disease.

Women with RA are also more likely to experience loss of muscle mass — what doctors call sarcopenia — as well as increasing abdominal body fat combined with decreasing muscle mass — a phenomenon known as sarcopenic obesity.

These are the findings of Dr. Jon T. Giles at the Johns Hopkins University School of Medicine, Baltimore, Maryland and colleagues, who studied body composition of 189 men and women with RA and 189 controls matched for age and gender.

Tests showed that the women with RA were significantly more likely to have sarcopenia, have excess fat and have sarcopenic obesity. This was not seen among men with RA or the controls.

Differences in body composition were greatest for patients with normal weight and normal body mass index — an accepted means of determining how fat or thin a person is.

Abnormal body composition was significantly related to a number of factors including an increasing number of deformed joints, higher levels of disability, elevated levels of the inflammatory protein CRP, and lack of treatment with "disease-modifying" anti-RA drugs, according to the researchers.

Abnormal body fat distribution is "over-represented in patients with RA, particularly in those in the normal weight BMI range," the investigators conclude, and RA-associated disease and treatment characteristics contribute to this increase in abnormal body composition.