Published 1/1/2009

Second Look

If you missed these Headline News Now items the first time around, AAOS Now gives you a second chance to review them. Headline News Now—the AAOS thrice-weekly, online update of news of interest to orthopaedic surgeons—brings you the latest on clinical, socioeconomic, and political issues, as well as important announcements from AAOS.

Joint replacements increasing
study published in the November/December issue of the journal Health Affairs projects that the number of hip and knee replacements may increase to as many as 4.5 million by the year 2030, placing a strain on the U.S. healthcare system. The authors find that much of the rising cost of such procedures can be attributed to the implant materials.

TKR improves overall physical functioning in older patients
Total knee replacement (TKR) may not only improve knee mobility in older adults with

severe osteoarthritis of the knee, but it may actually improve the patient’s overall level of physical functioning, according to a study published in Arthritis & Rheumatism. The authors used Medicare claims data to identify patients with osteoarthritis of the knee who were treated (n = 259) or were not treated (n = 1,816) with TKR from 1992 to 2003. Between baseline and outcome assessments, TKR recipients saw statistically significant improvements on three levels of physical functioning, while physical functioning in the no-treatment group declined.

Patient selection key in hip resurfacing
A patient’s age and gender are key to the success of hip resurfacing as an alternative to conventional hip replacement, according to a
study published in Clinical Orthopaedics and Related Research. Data from the first 537 hip resurfacing surgeries performed in the United States show serious complications occurred in 32 cases, primarily in women of all ages and men older than 55. Eight of the fractures occurred when the surgeon was relatively inexperienced with the procedure (within the surgeon’s first 10 cases).

Electrical stimulation for long bone fractures
A systematic review and meta-analysis of 11 randomized controlled trials finds that the impact of electrical stimulation on delayed unions or on nonunions of long bone fractures is inconclusive. Evidence from four trials (reporting on 106 delayed or ununited fractures) established an overall relative risk of 1.76 in favor of electromagnetic stimulation; single studies found a positive benefit on callus formation in femoral intertrochanteric osteotomies. However, a pooled analysis showed no significant impact of electromagnetic stimulation on delayed unions or nonunions of long bone fractures. Methodological limitations and high between-study heterogeneity leave the impact on fracture healing uncertain. The
study was published in the Nov. 1, 2008 issue of the Journal of Bone and Joint Surgery—American (JBJS–A).

C. difficile infections increasing
article published in the New England Journal of Medicine summarizes recent changes in the epidemiology of Clostridium difficile, discusses changes in disease severity and response to therapy, and reviews new approaches to the management of this increasingly problematic pathogen. Mutations in C. difficile have resulted in more prevalent and virulent infections. By 2005, the number of reported cases (84 per 100,000) was nearly three times the 1996 rate (31 per 100,000).

An article published in the October 2008 issue of AAOS Now also takes a look at the C. difficile problem.

Ultrasound may help break up blood clots faster
According t
o data presented at the VEITH symposium—an annual meeting of vascular specialists—using ultrasound waves in conjunction with clot-dissolving drugs for deep vein thrombosis (DVT) may help dissolve blood clots more quickly than using clot-dissolving drugs alone. The research team treated 37 thrombosis patients with tissue plasminogen activator (tPA)—a clot-dissolving drug—while using ultrasound to loosen the proteins in blood clots and send the drug into the clots faster. Overall, 16 patients had DVT and 21 had acute in situ arterial thrombosis. Clots dissolved completely in all the patients with arterial thrombosis and in 10 of the DVT patients. Of the remaining six DVT patients, four had their clots partially dissolved and two saw no change. Among the patients in the study group, one complication developed—a neck hematoma.

ACL reconstruction benefits older patients
According to the results of a
study published in JBJS–B, anterior cruciate ligament (ACL) reconstruction in carefully selected patients aged 50 years or older can achieve results similar to those in younger patients, with no increased risk of complications. The research team reviewed the records of 34 patients aged 50 years or older who underwent primary ACL reconstruction (35 knees) between 1990 and 2002. The authors noted postsurgery improvements in mean knee extension and flexion, Lachman grade, International Knee Documentation Committee scores, and Lysholm scores.

Proactive initiatives can reduce hip fracture rates
study published online by JBJS–A finds that proactive measures can reduce hip fracture rates by an average of 37.2 percent among those at risk. The 5-year study tracked more than 625,000 male and female patients older than 50 in California who had specific risk factors for osteoporosis or hip fractures. The implementation of initiatives such as increasing the use of bone density tests (DXA scans) and antiosteoporosis medications; adding osteoporosis education and home health programs; and standardizing the practice guidelines for osteoporosis management reduced hip fracture rates beyond the goal rate of 25 percent.

According to another study, published in JBJS–A, orthopaedists who take an active role in the management of osteoporosis can improve the rate of treatment at 6 months following a hip fracture. Researchers conducted a prospective randomized study of 62 patients, and found that the percentage of patients on pharmacologic treatment for osteoporosis at 6 months post-fracture was significantly greater when the evaluation was initiated by the orthopaedic surgeon and managed in a specialized orthopaedic osteoporosis clinic (58 percent) than when treatment was managed by a primary care physician (29 percent).

FDA issues update on bisphosphonates and cardiac events
The Food and Drug Administration (FDA) reviewed data on 19,687 patients treated with bisphosphonates and 18,358 controls who were followed for 6 months to 3 years. According to a recent FDA
update, the occurrence of atrial fibrillation was rare, and no clear association between overall bisphosphonate exposure and the rate of serious or nonserious atrial fibrillation was observed. Healthcare professionals should not alter their prescribing patterns for bisphosphonates and patients should not stop taking their bisphosphonate medication.

MRI study finds new injuries in young gymnasts
study presented at the annual meeting of the Radiological Society of North America finds that adolescent gymnasts are developing a variety of arm, wrist, and hand injuries beyond the scope of previously described gymnastic-related trauma. The research team used magnetic resonance imaging (MRI) to study overuse injuries seen in skeletally immature wrists and hands of 125 gymnasts, ages 12 to 16, including 12 patients with chronic wrist or hand pain. They found potentially preosteoarthritic injuries at “every step” from the radius to the ends of the finger bones at the knuckles.

Impact of corticosteroids on bones
According to research presented at the annual meeting of the American College of Allergy, Asthma and Immunology, neither oral corticosteroid bursts or inhaled corticosteroids were significantly related to the incidence of fractures. Corticosteroids, used in the treatment of asthma, are often associated with side effects such as decreased bone mineral density and reduced bone mass, and in children, with a reduction in growth rate. An
analysis of several large population databases found a small increase in fracture risk in adult users of inhaled steroids compared to controls. The risk of fracture, however, was similar for both inhaled steroid users and individuals using inhaled bronchodilators, suggesting that the increased risk of fracture was secondary to the disease itself.

Antibacterial use and drug-resistant bacteria on the rise
Total antibacterial use in adults increased significantly from 2002 through 2006 among a sample of academic health centers, according to a
study published in the Nov. 10, 2008 issue of the journal Archives of Internal Medicine. A total of 775,731 adult patients were discharged from 35 hospitals during 2006, and 492,721 (63.5 percent) received an antibacterial drug. The mean total antibacterial use increased from 798 days of therapy per 1,000 patient days in 2002 to 855 in 2006. Antibacterial drug use is a major risk factor for bacterial resistance.

FRAX® tool helpful for assessing treatment
published in the journal Osteoporosis International finds that the World Health Organization fracture risk assessment tool (FRAX®) is more accurate than bone mineral density measurements in identifying osteoporosis patients who needs more tests or treatment. FRAX predicts the 10-year risk of a patient sustaining a fracture based on his or her age, sex, weight, height, femoral BMD, and other factors.