One-third of knee replacements classified as inappropriate

Call for consensus on criteria for patient selection

2014-06-30

(Press-News.org) New research reports that more than one third of total knee replacements in the U.S. were classified as "inappropriate" using a patient classification system developed and validated in Spain. The study, published in Arthritis & Rheumatology, a journal of the American College of Rheumatology (ACR), highlights the need for consensus on patient selection criteria among U.S. medical professionals treating those with the potential need of knee replacement surgery.

The Agency for Healthcare Research and Quality reports more than 600,000 knee replacements are performed in the U.S. each year. In the past 15 years, the use of total knee arthroplasty has grown significantly, with studies showing an annual volume increase of 162% in Medicare-covered knee replacement surgeries between 1991 and 2010. Some experts believe the growth is due to use of an effective procedure, while others contend there is over-use of the surgery that relies on subjective criteria.

The present study led by Dr. Daniel Riddle from the Department of Physical Therapy at Virginia Commonwealth University in Richmond, examined the criteria used to determine the appropriateness of total knee arthroplasties. "To my knowledge, ours is the first U.S. study to compare validated appropriateness criteria with actual cases of knee replacement surgery," said Dr. Riddle.

A modified version of the appropriateness classification system developed by Escobar et al. along with the Western Ontario and McMaster Universities Arthritis Index (WOMAC) Pain and Physical Function scales were used to assess participants enrolled in the Osteoarthritis Initiative—a prospective 5-year study funded in part by the National Institutes of Health (NIH). There were 175 subjects who underwent total knee replacement surgery, and were classified as appropriate, inconclusive, or inappropriate.

The mean age of knee replacement patients was 67 years and 60% of the group was female. Analyses show that 44% of surgeries were classified as appropriate, 22% as inconclusive, and 34% deemed inappropriate. The characteristics of patients undergoing surgery were varied.

"Our finding that one third of knee replacements were inappropriate was higher than expected and linked to variation in knee pain OA severity and functional loss. These data highlight the need to develop patient selection criteria in the U.S.," concludes Dr. Riddle.

In a related editorial, Dr. Jeffery Katz from the Orthopedic and Arthritis Center for Outcomes Research at Brigham and Women's Hospital in Boston, Mass., writes, "I agree with Riddle and colleagues, and with Escobar and colleagues, that we should be concerned about offering total knee replacements to subjects who endorse "none" or "mild" on all items of the WOMAC pain and function scales."

INFORMATION: Dr. Katz also calls for an update to the criteria used to determine which patients are good candidates for total knee arthroplasty. Dr Katz's work is supported in part by a grant from the NIH (P60AR047782).

This study is published in Arthritis & Rheumatology. Media wishing to receive a PDF of this article may contact sciencenewsroom@wiley.com.

Full citation: "Using a Validated Algorithm to Judge the Appropriateness of Total Knee Arthroplasty in the United States: A Multi-Center Longitudinal Cohort Study." Daniel L. Riddle, William A. Jiranek and Curtis W. Hayes. Arthritis & Rheumatology; Published Online: June 30, 2014 (DOI: 10.1002/art.38685).

URL Upon Publication: http://doi.wiley.com/10.1002/art.38685 Editorial: "Appropriateness of Total Knee Replacement." Jeffrey N. Katz, Arthritis & Rheumatology; Published Online: June 30, 2014 (DOI: 10.1002/art.38688).

URL Upon Publication: http://doi.wiley.com/10.1002/art.38688

About the Authors: To arrange an interview with Dr. Riddle, please contact Eric Peters with Virginia Commonwealth University at +1 804-828-0563 or petersem@vcu.edu. Media wishing to speak with Dr. Katz may contact Jessica Maki with Brigham & Women's Hospital at jmaki3@partners.org.

About the Journal Arthritis & Rheumatology is an official journal of the American College of Rheumatology (ACR) and covers all aspects of inflammatory disease. The American College of Rheumatology is the professional organization whose members share a dedication to healing, preventing disability, and curing the more than 100 types of arthritis and related disabling and sometimes fatal disorders of the joints, muscles, and bones. Members include practicing physicians, research scientists, nurses, physical and occupational therapists, psychologists, and social workers. The journal is published by Wiley on behalf of the ACR. For more information, please visit http://wileyonlinelibrary.com/journal/art.

About Wiley Wiley is a global provider of content-enabled solutions that improve outcomes in research, education, and professional practice. Our core businesses produce scientific, technical, medical, and scholarly journals, reference works, books, database services, and advertising; professional books, subscription products, certification and training services and online applications; and education content and services including integrated online teaching and learning resources for undergraduate and graduate students and lifelong learners.

Founded in 1807, John Wiley & Sons, Inc. (NYSE: JWa, JWb), has been a valued source of information and understanding for more than 200 years, helping people around the world meet their needs and fulfill their aspirations. Wiley and its acquired companies have published the works of more than 450 Nobel laureates in all categories: Literature, Economics, Physiology or Medicine, Physics, Chemistry, and Peace. Wiley's global headquarters are located in Hoboken, New Jersey, with operations in the U.S., Europe, Asia, Canada, and Australia. The Company's website can be accessed at http://www.wiley.com.

[Attachments] See images for this press release:

One-third of knee replacements classified as inappropriate 2

ELSE PRESS RELEASES FROM THIS DATE:

Young teens who receive sexts are 6 times more likely to report having had sex

2014-06-30

A study from USC researchers provides new understanding of the relationship between "sexting" and sexual behavior in early adolescence, contributing to an ongoing national conversation about whether sexually explicit text messaging is a risk behavior or just a technologically-enabled extension of normal teenage flirtation. The latest research, published in the July 2014 issue of the journal Pediatrics, found that among middle school students, those who reported receiving a sext were 6 times more likely to also report being sexually active. While past research has examined ...

The outcome of fertility treatments using donor sperm is dependent on the quality of sperm

2014-06-30

Munich, 30 June 2014: Despite emerging evidence of a decline in sperm quality with increasing age, an analysis of every first fertility treatment cycle performed in the UK using sperm donation shows that outcome in terms of live birth is not affected by the age of the sperm donor. Results from the study, said its principal investigator Dr Meenakshi Choudhary, from the Newcastle Fertility Centre at Life, Newcastle upon Tyne, United Kingdom, reaffirm the observation that a couple's fertility appears significantly more dependent on the age of the female partner than on that ...

Researchers estimate 5.8 million A&E visits occur after patients unable to see a GP

2014-06-30

Researchers have estimated that in 2012-2013 there were 5.77 million A&E attendances in England that were preceded by an inability to get a timely GP appointment. Unplanned attendances at accident and emergency (A&E) departments in England have increased by 11 per cent (2.2 million attendances) between financial years 2008-2009 and 2012-2013. Recent reviews and research based on interviews have suggested that a reason for some attendances is that people who cannot obtain a GP appointment, or one they consider timely, visit A&E as an alternative. This is the first study ...

Countdown to 2015 and beyond: Fulfilling the health agenda for women and children

2014-06-30

The Lancet today [Monday 30 June] publishes a new Review from the Countdown to 2015 collaboration, summarising results from the Countdown 2014 report, examining the data supporting evidence-based decisions in women's and children's health, describing elements of the Countdown process that might inform ongoing efforts to hold the world to account for progress, and listing concrete steps that can be taken now to ensure continued progress for women and children. The Review is published to coincide with the 2014 Partners' Forum, held in Johannesburg, South Africa from June ...

Watching individual neurons respond to magnetic therapy

2014-06-29

DURHAM, N.C. -- Engineers and neuroscientists at Duke University have developed a method to measure the response of an individual neuron to transcranial magnetic stimulation (TMS) of the brain. The advance will help researchers understand the underlying physiological effects of TMS -- a procedure used to treat psychiatric disorders -- and optimize its use as a therapeutic treatment. TMS uses magnetic fields created by electric currents running through a wire coil to induce neural activity in the brain. With the flip of a switch, researchers can cause a hand to move or ...

A single gene separates aggressive and non-aggressive lymphatic system cancer

2014-06-29

WASHINGTON — For a rare form of cancer called thymoma, researchers have discovered a single gene defining the difference between a fast-growing tumor requiring aggressive treatment and a slow-growing tumor that doesn't require extensive therapy. Thymoma is a cancer derived from the epithelial cells of the thymus, an organ critical to the lymphatic system where T-cells, or so-called "killer cells," mature. Very little is known about the role of the gene mutation GTF2l in human tumors, but scientists from Georgetown Lombardi Comprehensive Cancer Center and the National Cancer ...

High CO2 levels cause warming in the tropics

2014-06-29

The impact of the greenhouse gas CO2 on the Earth's temperature is well established by climate models and temperature records over the past 100 years, as well as coupled records of carbon dioxide concentration and temperature throughout Earth history. However, past temperature records have suggested that warming is largely confined to mid-to-high latitudes, especially the poles, whereas tropical temperatures appear to be relatively stable: the tropical thermostat model. The new results, published today in Nature Geoscience, contradict those previous studies and indicate ...

Single-pixel 'multiplex' captures elusive terahertz images

2014-06-29

CHESTNUT HILL, MA (June 29, 2014) – A novel metamaterial enables a fast, efficient and high-fidelity terahertz radiation imaging system capable of manipulating the stubborn electromagnetic waves, advancing a technology with potential applications in medical and security imaging, a team led by Boston College researchers reports in the online edition of the journal Nature Photonics. The team reports it developed a "multiplex" tunable spatial light modulator (SLM) that uses a series of filter-like "masks" to retrieve multiple samples of a terahertz (THz) scene, which are ...

Marine bacteria are natural source of chemical fire retardants

2014-06-29

Researchers at the University of California, San Diego School of Medicine have discovered a widely distributed group of marine bacteria that produce compounds nearly identical to toxic man-made fire retardants. Among the chemicals produced by the ocean-dwelling microbes, which have been found in habitats as diverse as sea grasses, marine sediments and corals, is a potent endocrine disruptor that mimics the human body's most active thyroid hormone. The study is published in the June 29 online issue of Nature Chemical Biology. "We find it very surprising and a tad alarming ...

NIH-funded researchers extend liver preservation for transplantation

2014-06-29

Researchers have developed a new supercooling technique to increase the amount of time human organs could remain viable outside the body. This study was conducted in rats, and if it succeeds in humans, it would enable a world-wide allocation of donor organs, saving more lives. The research is supported by National Institute of Biomedical Imaging and Bioengineering (NIBIB) and the National Institute of Diabetes and Digestive and Kidney Disease (NIDDK), both parts of the National Institutes of Health. The first human whole organ transplant 60 years ago—a living kidney ...

One-third of knee replacements classified as inappropriate

ELSE PRESS RELEASES FROM THIS DATE:

LAST 30 PRESS RELEASES: