Forced air warming devices are in widespread use in our orthopaedic surgical suites—and for good reason: Hypothermia can be a major factor in poor patient outcomes due to its negative impact on myocardial function, pharmacokinetics, and other aspects of patient physiology. While maintaining normothermia in surgical patients lowers the risk of postoperative surgical site infections, recent literature has raised concerns about an increased risk of infection in arthroplasty cases in which forced air warming was used.
The December 17, 2014 JBJS literature review by Sikka et al. focuses on this conundrum. It is a well-written summary of current knowledge that clearly outlines the deficiencies in the available data. The authors emphasize that the studies yielding both positive and negative findings are in most cases tainted with detection and selection bias related to industry-funded research designs. This is an area that is begging for a large randomized controlled trial.
However, because of the <1% overall incidence of infection following lower-limb arthroplasty, such a trial will require large numbers of patients. Also essential for such an investigation will be an experienced clinical trialist, meticulous methods, and an apriori definition of “infection.” It is doubtful that registry data analysis can adequately determine the efficacy of forced air warming in preventing major intraoperative adverse events or its impact on postoperative infection, but an analysis of all available data would be a good start.
I look forward to future well-designed studies in this area that will further clarify patient benefit as well as risk. In the meantime, Sikka et al. stress the importance of following all manufacturer instructions for use and maintenance of any patient-warming device.
Marc Swiontkowski, MD
Perhaps more than any other advance in orthopaedic surgery, total joint arthroplasty has improved the lives of millions of patients. Originally introduced in the form of hip replacement, nearly all of the major joints of the musculoskeletal system can now undergo arthroplasty, and total knee arthroplasty has established itself as one of the most successful interventions for reducing pain and improving function and quality of life. All total joint arthroplasties are associated with a risk of failure, and it is believed that, with the exception of the oldest patients, most individuals who undergo an arthroplasty will require a revision at some point during their lifetime. With total knee arthroplasty, advances in implant materials and design as well as operative technique have increased implant longevity and decreased the rate of revision to <5% within ten years.
As is typical of a successful intervention, surgeons who perform total knee arthroplasty recognize the need or opportunity to “push the envelope.” There is great demand for offering knee arthroplasty to younger, more active patients, and, in doing so, it is projected that the number of revision procedures will grow from the current annual incidence of 38,000 up to 270,000 by the year 2030. Thus, understanding the causes of failure will be essential for guiding future strategies.
In this month’s article by Bou Monsef et al., a systematic approach to identifying mechanisms of failure and appropriate treatment protocols for failed total knee arthroplasty are introduced. The authors make the important point that avoiding operative intervention before a diagnosis is made, even in cases of pain with no clear etiology, is essential. Individual discussions on the roles of infection, loosening and component failure, instability, stiffness, patellofemoral complications, and even neuromas are presented and placed in their proper perspective.
Indeed, one of the greatest frustrations in orthopaedic practice is the inability to identify the causative factors for a condition. The failure of a total knee arthroplasty may be associated with one or more contributing factors, including rare and unusual conditions such as the formation of heterotopic bone, the development of complex regional pain syndrome, the occurrence of hemarthrosis, and even hypersensitivity to certain metals. Interestingly, up to 17% of the general population expresses some sensitivity to the metals used in total knee implants such as nickel, chromium, and cobalt.
Failure of total knee arthroplasty can be devastating to the patient, but early diagnosis and careful systematic analysis of the potential etiologies can lead to a favorable outcome. This article provides a clear and concise approach to this problem and is a “must read” for surgeons who perform this operation now and the residents and fellows who will be caring for these patients in the decades to come.
Thomas A. Einhorn, MD, Editor
Here are a few excerpts from the JBJS conversation with Dr. Jo Hannafin, President of AOSSM (American Orthopaedic Society for Sports Medicine).
JBJS: You were recently elected the first woman president of AOSSM – what significance do you see in that fact?
Dr. Jo Hannafin: My election to the AOSSM presidency reflects the breadth of membership in the AOSSM and the slowly changing face of orthopaedic surgery. Our goal as educators and surgeons is to bring the best and brightest medical students into our field and this includes men, women and individuals with diverse racial and ethnic backgrounds.
JBJS: What are your key goals for your presidency?
Dr. Jo Hannafin: My goals as president are to increase engagement of the membership in the AOSSM via volunteerism (committee involvement), attendance at specialty day and the annual meeting, and by providing continued opportunities for community education by our members via the STOP Sports Injury program started by Dr. James Andrews.
JBJS: How do you think JBJS can best address the needs of the members of AOSSM and other sub-specialty organizations?
Dr. Jo Hannafin: JBJS can address the needs of orthopaedic surgeons by partnering in webinar programs and by continuing to publish high quality manuscripts in subspecialty areas.
JBJS: What trends in orthopaedics/sports medicine are you most intrigued by?
Dr. Jo Hannafin: The identification of biomarkers with early association with trauma or sports injury has the potential to modify the development of post-traumatic arthrosis. This idea is particularly compelling in sports injuries such as the acute ACL. The frequency of this injury continues to increase, and we are seeing younger athletes sustaining this injury. The continued attention to the development and validation of injury prevention programs provides opportunity for risk modification.
The use of biologic therapy in sports medicine, such as stem cell transplantation and PRP, may have the potential to treat sports injuries, but the clinical use of these treatments needs to be carefully studied and validated.
JBJS: What at are your expectations of changes to come as a result of the Affordable Care Act (ACA)?
Dr. Jo Hannafin: The ACA is an extraordinarily complex document and quite honestly, with a few exceptions, I don’t think we know what it will bring. The ACA will provide health insurance to a large number of previously uninsured or uninsurable people (those with pre-existing conditions). The volume of patients seeking care will increase, and that has the potential to stress the existing system. Reimbursement for orthopaedic care will likely be modified and requires the careful attention of our members, hospital systems, specialty organizations, and the AAOS.
JBJS: Looking ahead to the next 20 years or so, what do you think might be three significant advances or changes in orthopaedics?
Dr. Jo Hannafin: I anticipate that scientists will be able to identify biomarkers associated with acute injury and physicians/surgeons will have the capacity to modify the response to catabolic agents, thus preventing the development of post-traumatic arthrosis. The field of biomechanical engineering will provide surgeons with improved scaffolds which when combined with biologic therapies will permit restoration of bone, cartilage, and ligaments. The field of total joint arthroplasty will benefit from continued interaction with scientists to optimize interface mechanics and prolong the lifetime of arthroplasty implants.
JBJS: You recently participated in a webinar co-sponsored by JBJS and JOSPT. Do you see benefits from greater teamwork among different types of health-care providers? If so, what are the most important benefits? What barriers remain to greater collaboration?
Dr. Jo Hannafin: Teamwork and interaction between providers of musculoskeletal care will continue to grow and will be necessary as the volume of patients treated increases. We need to define the scientific benefits of conservative and surgical treatments for musculoskeletal conditions, and this will require interactions between scientists, physicians, surgeons, and physical therapists. The questions posed during the adhesive capsulitis webinar reflected input from both surgeons and physical therapists and helped each group to understand the issues associated with treatment. The ultimate benefit of this interaction is improved patient care, which is important to all of us. The biggest barrier is time!
JBJS: You have recently overcome some serious health issues. It’s great to hear that you are doing well. Has this experience changed the way you approach your patients?
Dr. Jo Hannafin: The last two years of my life have been marked by highs and lows. My election to the presidency of the AOSSM, and the associated opportunities, has been personally and professionally fulfilling. In April 2012 I was diagnosed with early multiple myeloma, which was treated at Dana Farber Cancer Institute with chemotherapy followed by an autologous stem cell transplant. The experience was the most difficult challenge that I have faced but I received incredible support from family, friends, patients and AOSSM colleagues from across the country. I am happy to report that my health is excellent and I have been back to a normal schedule for almost one year. The experience reinforced the need for careful and thoughtful communication with our patients.
JBJS: What is your favorite thing about your profession?
Dr. Jo Hannafin: As a sports medicine specialist, I love taking care of athletes and active people of all ages. While many sports related injuries do not require surgery, it is especially gratifying as a surgeon to restore function via repair and reconstruction of injured structures, permitting return to sports or fitness activities.
JBJS: Thank you, Dr. Hannafin for sharing this time with us. We look forward to speaking with you again in the near future.