The US FDA has approved the Synovasure Alpha Defensin Lateral Flow Test Kit for helping detect periprosthetic joint infection (PJI) in the synovial fluid of patients being evaluated for revision joint replacement.
Alpha defensins are proteins released by neutrophils in early response to infection. OrthoBuzz previously summarized a 2018 JBJS study that found this rapid alpha defensin test to have 96.9% overall accuracy.
In the FDA news release about the approval, Tim Stenzel, MD, director of the FDA’s Office of In Vitro Diagnostics and Radiological Health, said the test provides health care professionals with additional information that “could potentially reduce patient risk by avoiding unnecessary revision operations for replacement joints.”
In a Commentary on the 2018 JBJS study, Garth Ehrlich, PhD and Michael Palmer, MD said the device is a “substantive advance,” but not “a panacea.” For one thing, metallosis would still need to be ruled out with MRI, because that noninfectious etiology triggers a false-positive result with this rapid test. Synovasure is also likely to miss detection of slow-growing, chronic bacterial pathogens such as Proprionibacterium acnes, the commentators said.
The Synovasure test kit received approval through the FDA’s de novo premarket pathway, which is reserved for “low- to moderate-risk devices of a new type,” according to the agency.
We have entered an era where total ankle arthroplasty (TAA) is accepted as a rational approach for patients with degenerative arthritis of the ankle. TAA results have been shown to be an improvement over arthrodesis in some recent comparative trials.
That was not always the case, however. In the 1980s, the orthopaedic community attacked ankle joint replacement with gusto, and numerous prosthetic designs were introduced with great enthusiasm based on short-term cohort studies. Unfortunately, the concept of TAA was all but buried as disappointing longer-term results with those older prosthetic designs appeared in the scientific literature. It took a full decade for new designs to appear and be subjected to longer-term follow-up studies before surgeons could gain ready access to more reliable instrumentation and prostheses. The producers of these implants behaved responsibly in this regard, facilitated by an FDA approval process that had increased in rigor.
In the December 21, 2016 issue of The Journal, Hofmann et al. publish their medium-term results with one prosthetic design that was FDA-approved in 2006. Implant survival among 81 consecutive TAAs was 97.5% at a mean follow-up of 5.2 years. There were only 4 cases of aseptic loosening and no deep infections in the cohort. Total range of motion increased from 35.5° preoperatively to 39.9° postoperatively.
The fact that a high percentage (44%) of ankles underwent a concomitant procedure at the time of TAA attests to the need for careful preoperative planning for alignment of the ankle joint and the need for thorough assessment of the hindfoot. The fact that a substantial percentage (21%) of ankles underwent another procedure after the TAA attests to the need for thoughtful benefit-risk conversations with patients prior to TAA.
I think the TAA concept and procedure are here to stay, but we still have much work to do in fine-tuning prosthetic designs and instrumentation and enhancing surgeon education for more reliable outcomes.
Marc Swiontkowski, MD
The July 6, 2016, edition of The Journal of Bone & Joint Surgery features a large case-cohort study that may help older patients and clinicians decide whether to use bone morphogenetic protein (BMP) as an adjunct to lumbar arthrodesis. Among Medicare patients aged 65 years and older, Beachler et al. found that BMP use was not associated with the following:
- Overall cancer risk
- Increased risk of individual cancer types
- Increased risk of cancer in people who had cancer prior to undergoing lumbar arthrodesis
- Increased mortality after a cancer diagnosis
BMP was used in 30.7% of >3,600 lumbar-arthrodesis patients analyzed, and the lack of association between BMP use and cancer held whether patients received the growth factor as part of an FDA-approved anterior lumbar interbody fusion or as an off-label application.
In an accompanying commentary, Singh et al. laud the authors for designing a study that was not only well-powered but also analyzed risk among those with a medical history of cancer. The commentators emphasize, however, that the median follow-up in this study was 2.4 years, leading them to wonder “whether this time frame is sufficient to evaluate the impact of BMPs on carcinogenesis.”
Until a large, prospective, randomized trial on this subject is conducted, Singh et al. say, “the decision to use BMPs should be made on the basis of sound clinical judgment by the treating physician after a full disclosure of the potential risks to the patient.”
BMJ recently published two studies of interest to orthopaedists:
- After analyzing data from more than 200 cardiovascular, orthopaedic, and neurologic devices approved in both the US and European Union (EU), Hwang et al. found that those approved in the EU first were nearly three times as likely to trigger a safety alert or experience a recall than those first approved in the US. Finding further that trial results were published for fewer than half of approved devices considered “major innovations,” the authors call for “greater regulatory transparency” so physicians and patients can make better-informed decisions. Interestingly, Figure 2 in this study showed that the FDA approval time for orthopaedic devices was faster than ortho-device approval times in the EU. However, a JBJS study earlier this year found that devices approved via the FDA’s “quick” 510(k) process were 11.5 times more likely to be recalled than those cleared through the longer and more stringent FDA pathway.
- In the second BMJ article, a registry-based case-control study, Abrahamsen et al. found that the long-term use of the bisphosphonate alendronate does not increase the risk for atypical femoral fractures (either subtrochanteric or femoral shaft), while protecting against hip fractures. After applying some sophisticated statistical analyses, the authors estimated that 38 patients with ≥5 years of alendronate adherence would need to be treated for an additional 5 years to prevent one hip fracture, while 1449 similar patients would need to be treated to cause an atypical femoral fracture. Click here for more OrthoBuzz coverage of the relationship between bisphosphonates and atypical femoral fractures.
Most orthopaedic devices are cleared through the FDA’s 510(k) process. But an analysis in the March 16, 2016 JBJS by Day et al. revealed that 510(k)-cleared devices were 11.5 times more likely to be recalled than devices cleared through the more stringent Premarket Approval (PMA) process.
The authors encourage orthopaedic surgeons who are thinking about using a new device in patients to consider how the device was approved. “If the device was approved by the 510(k) pathway, then it may have been approved without additional clinical studies confirming efficacy or safety,” they caution.
The pie chart above shows that from November 2002 to December 2012, 41% of all recalled devices from the 20 companies with the highest number of recalls were of orthopaedic origin.
In late April, the FDA issued a safety announcement cautioning that corticosteroids delivered by epidural injection to treat back and neck pain may cause “rare but serious adverse events”–including vision loss, stroke, paralysis, and death. The agency is requiring an additional label warning to increase awareness of the risks, which were confirmed after the FDA reviewed cases from its Adverse Event Reporting System. Although anesthesiologists, physiatrists, and specialists other than orthopaedic surgeons often administer such injections, orthopaedists should note that as far as the FDA is concerned, the safety and efficacy of epidural steroid injections for neck and back pain have not been established. The FDA said it plans to convene an advisory committee later this year to “discuss the benefits and risks of epidural corticosteroid injections and to determine if further FDA actions are needed.”
Orrin Franko, MD is a fifth-year orthopaedic surgery resident at University of California, San Diego. He has an interest in researching and promoting the orthopaedic uses of social media and mobile apps. In addition to multiple publications on these subjects, Dr. Franko is the founder and creator of TopOrthoApps.com, a website that reviews mobile apps for orthopaedic surgeons. We appreciate his willingness to answer a few questions for OrthoBuzz.
JBJS: Looking back on this year’s AAOS Annual Meeting in New Orleans, what were some of the highlights for you?
Dr. Franko: I was impressed by the combination of traditional posters, digital videos, and presentations. With regard to mobile technology, I was pleasantly surprised to see such a dramatic increase from just two years ago. This year I saw four posters that developed or validated a smartphone or tablet app for clinical use and patient care, something that I have never seen before. On the exhibit floor, iPads are now a ubiquitous platform for displaying education about products, and many new products integrate wireless capabilities and iPad functionality directly into their use.
JBJS: You presented several times in the Electronic Skills Pavilion at AAOS. Tell us a bit about the sessions and the audience response.
Dr. Franko: The Electronic Skills Pavilion provides a unique presentation opportunity for surgeons to give 45-minute talks on a variety of technology-related topics such as social media, practice websites, search engine optimization, and digital photography and videography. This year, I gave three talks on using mobile apps (iPad and iPhone) for education, patient information, and practice enhancement. The talks were very well attended, which suggests to me that surgeons are eager to learn how to use technology to improve their practice and efficiency.
JBJS: How have you seen the attitudes of orthopaedic surgeons toward mobile technology and apps change over the past 3 years?
Dr. Franko: The past 3 years have shown a clear up-trend in the prevalence and use of apps in hospitals and clinics among both residents and surgeons. This is reflected not only in my personal experience, but also in various studies that have assessed mobile-device usage among all physicians and specifically among orthopaedic surgeons. Using a phone in the hospital is no longer a distraction; it’s a critical educational device.
JBJS: What would you say to orthopaedists who are concerned about HIPAA compliance when using apps?
Dr. Franko: HIPAA will always be a “hot topic” with regard to mobile and wireless devices. This stems from a combination of fear about new technologies that are not well understood, and from the learning curve associated with the introduction of any new technology. First, I would remind everyone that historical medical documentation and care utilized paper charts, standard phone lines, fax machines, and text pagers—none of which are encrypted or HIPAA-compliant. In contrast, mobile devices, text messages, phone calls, and email are much more easily encrypted and protected from data breaches.
Admittedly, these systems are not perfect and never will be. However, if appropriate steps are taken to reduce risks, most hospitals permit the use of all these devices. Generally speaking, surgeons should be aware of patient information that is stored directly on their device versus “in the cloud” (on a remote server at another location). And, if information is stored in the cloud, this should be encrypted at a minimum. I equate the current status of mobile technology for patient care to the off-label use of FDA-approved medical devices: as long as surgeons are aware of how these new technologies work and take measures to protect their patients while working within the restrictions of their hospitals, they should be able to safely implement information technologies that benefit their patients.
JBJS: How do you think JBJS can best address the needs of orthopaedic residents?
Dr. Franko: I think JBJS is taking important steps to address residents’ needs to obtain reliable, peer-reviewed orthopaedic information. As a result of Google, the current generation of residents is accustomed to free, unlimited, and contextually searchable information without delay. This is in stark contrast to searching for archived journal articles on library shelves. By providing fully searchable article titles and full text with the ability to download PDFs for offline viewing, JBJS allows residents to find the information they need when it’s needed. Whether this is provided via a traditional website or via a mobile app is a decision of the journal, but mobile apps have proven to be efficient and reliable tools for journal reading.
(Editor’s note: The recent launch of JBJS Reviews included a free app for use with iOS and Android devices.)
JBJS: What trends in orthopaedics are you most intrigued by?
Dr. Franko: I am most intrigued by the ability to engage patients in the mobile sphere and help them to be participants in their own care. The increase in medical knowledge is true not only for residents and surgeons, but also for patients. Our patients have the ability to learn more about their diseases and potential treatment options than ever before, and they present to our clinics and hospitals with sophisticated questions and expectations about their care. I would like to see technology bridge the gaps between physicians and patients with regard to education and outcomes, while also potentially collecting useful data that can help guide further treatment.
JBJS: Looking ahead to the next 20 years, what three significant advances or changes in orthopaedics do you foresee?
Dr. Franko: While I cannot predict the future, I am hopeful that we will see technology enhance three specific areas of orthopaedic surgery. First, I expect to see drastic changes in resident education that utilize a combination of new technologies to disseminate orthopaedic information. That will include interactive digital journal club discussions, video and web-cast surgical techniques, online board-preparation courses, and curriculum changes that accommodate new work-hour restrictions. Second, I anticipate that medical record digitization will no longer be a burden and will rather demonstrate its potential benefits by improving clinical efficiency, patient safety, and enhancing outcomes research. Third, I am interested in watching the transition to universal healthcare and its impact on healthcare economics and ultimately patient outcomes. This will, in turn, greatly influence practice models and surgeon compensation for my generation of surgeons. That, in turn, will affect the way medical advances are developed and introduced into the field.
JBJS: What is your favorite thing about your profession?
Dr. Franko: The patients. Every day I have the opportunity to help people who are deeply motivated to improve and return to activity, which motivates me to help them in any way possible. My second favorite aspect of my profession is having such diverse and open-minded colleagues who are both exceptional clinicians as well as researchers. As a result, there has been great interest in studying the utility of new technology for the benefit of patient care.