AAOS Now

Published 11/1/2008

Second Look – Clinical News and Views

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.

Surgeon General calls for action to address rise in DVT, PE
Steven K. Galson, MD, MPH, the acting U.S. Surgeon General, has issued a call to action to reduce the number of cases of deep vein thrombosis (DVT) and pulmonary embolism (PE) in the United States. DVT and PE together are estimated to contribute to at least 100,000 deaths and to affect approximately 350,000 to 600,000 Americans each year—numbers that are expected to increase as the U.S. population ages. The document urges a coordinated, multifaceted plan to reduce the incidence of DVT and PE nationally, and emphasizes the need for increased awareness about the conditions, evidence-based practices for DVT, and more research on the causes, prevention, and treatment of DVT.

The AAOS has developed clinical guidelines (PDF) on the prevention of symptomatic PE in patients undergoing total hip arthroplasty or total knee arthroplasty.

SPORT study: Lumbar diskectomy outcomes vary by herniation level
According to data from the Spine Patient Outcomes Research Trial (SPORT), the outcomes of lumbar diskectomy procedures vary by herniation level. SPORT’s initial findings showed an overall advantage for surgical treatment compared to nonsurgical treatment of lumbar disk herniations. A subsequent analysis of subgroups by actual treatment received stratified by level of disk herniation (646 L5-S1 herniations, 456 L4-L5 herniations, and 88 upper lumbar [L2-L3 or L3-L4] herniations) found that at 2 years, patients with upper lumbar herniations showed a significantly greater treatment effect from surgery than did patients with L5-S1 herniations for all outcome measures. Researchers also found a trend toward greater treatment effect for surgery at L4-L5 compared with L5-S1, but it was significant only for the SF-36 physical functioning subscale. Differences in treatment effects between the upper lumbar levels and L4-L5 were significant for SF-36 bodily pain only. The
study was published in the September issue of the American edition of the Journal of Bone and Joint Surgery.

CDC seeks info on liver failure after TKA
The U.S. Centers for Disease Control and Prevention (CDC) has been notified of three cases of severe, rapid-onset liver failure following total knee arthroplasty (TKA). All incidents occurred in a single hospital, with illness onset between Jan. 18, 2008, and Aug. 23, 2008. Severe hepatotoxicity developed in all patients; liver function tests were elevated (ALT and AST >10,000). The patients had no history of liver disease and had negative hepatitis serologies. The cause is under investigation and is suspected to be toxin-mediated. Physicians who are aware of similar cases are requested to contact their state or local health department or report cases directly to Dr. Sara Vagi (svagi@cdc.gov) or Colleen Martin (cmartin5@cdc.gov) in CDC’s Division of Environmental Hazards and Health Effects.

Adults have nearly 1-in-2 risk of knee OA by age 85
Osteoarthritis (OA) of the knee may develop in nearly half of adults in the United States by age 85, according to a
study published in the journal Arthritis Care and Research. The longitudinal study focused on 3,068 people aged 45 years or older who live in rural North Carolina. Patients were measured at baseline (1990–1997) and follow-up (1999–2003) for radiographic, sociodemographic, and symptomatic knee data. Among other findings, the research team determined that the overall lifetime risk of symptomatic knee OA was 44.7 percent. Cohort members with a history of a knee injury had a lifetime risk of 56.8 percent. Lifetime risk rose with increasing body mass index; the risk of development of knee OA among those who were obese was 2 in 3.