Additional Developments in One of Med-Tech's Key Sectors
Keeping you up to date on recent developments in orthopedics
MRI techniques can detect early osteoarthritis . . . Researchers from NYU Langone Medical Center's departments of orthopedic surgery and radiology found that advanced MRI techniques can be used to detect subtle changes in joint cartilage microstructure and provide physicians a diagnostic tool for finding key markers of early osteoarthritis (OA). By using these techniques during patient exams to identify OA earlier, clinicians can shift the management of the disease from eventual joint reconstruction to long-term preservation. The study was published in the July issue of the Journal of the American Academy of Orthopaedic Surgeons. “Imaging technology is now sensitive and powerful enough to enable detection of subtle changes in the intricate balance of water, chondrocytes and the collagen fibers and protein molecules that make up our joint cartilage which we now know can point to future osteoarthritis,“ says Laith Jazrawi, MD, associate professor of orthopedic surgery and lead author of the paper. “With an active and aging baby boomer population beginning to experience joint pain associated with age, we think there is great potential for bringing these imaging techniques from the lab to the benefit of patients.“ The clinical practice standard is to use conventional MRI imaging to assess the quality of cartilage in patients with joint pain, or known arthritis, which focuses on the morphological integrity of the cartilage. In the lab, however, radiologists, orthopedic surgeons, and rheumatologists working as a team have used advances in MRI technology and biochemical imaging techniques to assess cartilage damaged by osteoarthritis. Damaged cartilage shows distinct changes in the concentration of water and collagen molecules, the micro- and macrostructure of collagen, and the concentrations of particular proteins, glycosoaminoglycans. The findings support the use of these MRI techniques in the evaluation of younger patients with joint pain to identify the beginnings of OA allowing for earlier treatment to halt the progression of the disease. “The development and optimization of these innovative MR techniques has opened up a new window into the understanding and possible treatment of arthritis before irreversible structural and morphological changes has occurred,“ said Michael P. Recht, MD, Louise Marx professor of radiology and chairman of the Department of Radiology.
Gene variant in Proteus syndrome identified . . . Orthopedic surgeons from Children's National Medical Center (Washington) are part of a team of researchers that has identified the genetic mutation causing Proteus syndrome, a rare disorder in which tissue and bone grow massively out of proportion. The discovery appears in the July 27, online edition of the New England Journal of Medicine. The study, led by researchers at the National Human Genome Research Institute (NHGRI), part of the National Institutes of Health (NIH), may have larger implications in both the identification and treatment of Proteus syndrome, as well as for certain types of cancer. The NIH-based research team found that a point mutation – a single-letter misspelling in the DNA of the genetic code – in the AKT1 gene activates the sporadic tissue growth associated with Proteus syndrome. This particular genetic mutation in AKT1 is almost always undetectable in simple blood samples, making it necessary for surgical teams to collect and contribute deep tissues, including bone, cartilage, and growth plates, while patients with Proteus syndrome are undergoing necessary surgical procedures as part of their standard care. “Proteus syndrome is an extremely rare disorder, making tissue sample collection especially challenging,“ said Laura Tosi, MD, of the Division of Orthopedic Surgery and Sports Medicine at Children's National. “Given the importance of this research, we stepped up to the plate and, over the last decade, Children's National surgeons have collected more than one third of the study's tissue samples while Proteus syndrome patients underwent necessary procedures here at Children's National and at NIH.“
Could an “Ankle Hotline“ relieve strain on healthcare demands? . . . New study suggests that precious ER resources could be spared by finding alternative ways to assess and treat lower leg injuries. Should lower leg strains and sprains take up valuable ER time and resources? According to a new study by Kaj Lambers and colleagues, from Massachusetts General Hospital (Boston) strains and sprains account for over a third of lower extremity injuries treated at emergency departments. They reason that because these problems are not life-threatening, perhaps telephone triage and scheduled care appointments might be a better use of precious emergency healthcare resources. The work is published online in Clinical Orthopaedics and Related Research published by Springer. In order to prevent injuries, allocate resources more efficiently, and prioritize training, it is important to get an accurate picture of the number of patients and types of injuries presenting to emergency departments. Lambers and colleagues looked specifically at leg problems that bring patients to the ER. They analyzed data from the National Electronic Injury Surveillance System (NEISS) for 119,815 patients with lower extremity injuries in 2009. They wanted to determine the number of leg injuries by region and disease category, patients' age, circumstances of the injury, and where it occurred. They also looked at year-to-year consistency between 2000 and 2009 to get a picture of injury trends. They found that strains and sprains accounted for 36% of all lower extremity injuries, the most common of which was an ankle sprain - an injury most common in young adults and teenagers. Indeed, younger patients were more likely to have ankle sprains, foot contusions/abrasions, and foot strains/sprains. Older patients were more likely to have lower trunk (femoral neck, hip, pelvis, and lumbar vertebrae) fractures and lower trunk contusions/abrasions. The authors conclude: “Relatively low-severity lower extremity problems such as strains and sprains account for a substantial number of emergency department visits. Different approaches to triage and evaluation of lower extremity injury might result in better utilization of emergency healthcare resources. For instance, patients with ankle injuries might call an emergency phone number to be triaged for an urgent visit if necessary, or a scheduled visit during regular business hours instead.“
Joint replacement surgery increases risk of blood clot formation . . . A new study focusing on the occurrence of clots in knee replacement patients and published in a recent issue of the Journal of Bone and Joint Surgery (JBJS) indicates that despite treatment with blood thinners prior to and immediately following joint replacement surgery, the risk of clot formation is still relatively high in certain patients. “The rate of knee replacement has increased substantially worldwide, and continued increases are anticipated in the future,“ said study author Alma Pedersen, MD, PhD. “The formation of clots, including pulmonary emboli, is a serious complication in patients undergoing knee arthroplasty. Prophylactic measures, such as the use of blood thinners around the time of surgery, are used to reduce the occurrence of clots, but their effectiveness in routine clinical practice following surgery is more uncertain.“ The authors evaluated 37,223 knee replacement patients who had surgery between 1997 and 2007, looking for evidence of post-surgical embolism in the 90-day period following surgery. The authors found 441 patients (1.2%) were hospitalized for blood clots during the 90-day period following knee surgery. An in-depth evaluation of these patient records revealed the following risk factors associated with clot development: advanced age (older than 80 years of age); history of cardiovascular disease; history of previous clot; or increased number of accompanying medical conditions. The study also revealed the number of patients admitted to hospitals with clots following knee surgery has increased since 1997, which Pedersen noted is most likely due to advances in diagnosis which have enabled physicians to identify clots before they cause serious problems. The study also notes that individuals who have a knee replacement surgery due to rheumatoid arthritis have a lower risk of clots than those with other conditions. However, in all patients, the risk can be diminished slightly by replacing only one knee at a time, rather than both. Although knee surgery is still a generally safe procedure, which enables thousands of men and women each year to regain mobility lost to injury or illness, patients should be aware of the risk of post-surgical clotting and talk with their physician about the possible use of blood thinners and follow-up evaluations that may help to identify clots which may be treated before they cause problems. Although blood thinners are typically prescribed only during hospitalization, the study suggested that physicians consider extending the duration of blood thinner therapy into the weeks following surgery. “Despite the use of blood thinners, patients undergoing knee arthroplasty continue to remain susceptible for clot formation for several weeks following surgery,“ Dr. Pedersen said. “Future studies should focus on the improvement of prophylaxis following hospital discharge, particularly among elderly patients and those with a history of cardiovascular diseases or previous clot formation.“
– Compiled by Holland Johnson, MDD