Alpha Defensin Lateral Flow Test for Diagnosis of Periprosthetic Joint Infection: Not a Screening but a Confirmatory Test
Determination of alpha defensin in synovial fluid has shown promising results for diagnosing periprosthetic joint infection (PJI). https://bit.ly/2rH8JuN #JBJSInfographics #JBJS
OrthoBuzz occasionally receives posts from guest bloggers. This guest post comes from Matthew Herring, MD, in response to a recent study in the Journal of Orthopaedic Trauma.
With many problems in orthopaedics, the best management options are still being debated. The treatment of femoral neck fractures is one such problem. Surgeons have several available options: cancellous screws (CS), a sliding hip screw (SHS), hemiarthroplasty, and total hip arthroplasty. The recently completed Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) randomized trial sought to offer insight on those treatment modalities.1 The study enrolled 1,079 patients with low-energy femoral neck fractures and randomized them into treatment with CS or SHS.
In a follow-up study published in the May 2018 edition of the Journal of Orthopedic Trauma, Sprague et al. analyzed FAITH data to identify predictors of revision surgery during 24 months after surgical fixation of a femoral neck fracture.2 Based on previously published studies, the authors identified 15 factors a priori that may be associated with revision surgery . Among the more than 800 patients in the FAITH cohort who had complete follow-up data, 191 (23%) underwent revision surgery and were included in the analysis. Proportional hazard modeling identified 5 factors associated with revision surgery: female sex (hazard ratio [HR], 1.79), body mass index (HR, 1.19—a 19% increased risk of revision for every 5-point increase in BMI), displaced fracture (HR, 2.16), Pauwels type III configuration (HR, 2.13 relative to type II), and poor implant positioning (HR, 2.70). In addition, prefracture dependence on assistive devices for ambulation was significantly associated with a risk of conversion to arthroplasty (p = 0.04), although a hazard ratio was not reported.
These important findings may help guide our decision making for the treatment of femoral neck fractures. First, male patients may be better candidates for surgical fixation of neck fractures than female patients, which probably relates to sex differences in bone density. Thinner patients also may be better candidates for femoral neck fixation, while arthroplasty may be the more reliable option for high-BMI patients.
Second, we have to pick the right fractures to fix. As is well described elsewhere in the literature, a more vertical fracture line (>50°) is more likely to fail with fixation. Additionally, patients with displaced fractures face a significantly higher risk of revision surgery and may be poor candidates for fixation.
Arguably, the most important modifiable risk factor for revision surgery is surgical technique. Unfortunately (and fortunately), in the FAITH study there were too few malreductions to investigate this variable in detail. However, poor implant positioning—defined as prominent screws at the lateral cortex, screw penetration, and lag screws positioned too high—was strongly associated with an increased risk of revision surgery.
It goes without saying, but well-placed implants perform better.
Matthew Herring, MD is a senior orthopaedic resident at the University of Minnesota and a member of the JBJS Social Media Advisory Board.
- Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) Investigators. Fracture fixation in the operative management of hip fractures (FAITH): an international, multicentre, randomised controlled trial. Lancet. 2017;389(10078):1519-1527.
- Sprague S, Schemitsch EH, Swiontkowski M, et al. Factors Associated With Revision Surgery After Internal Fixation of Hip Fractures. J Orthop Trauma. 2018;32(5):223-230.
On Thursday evening, June 28 and all day Friday, June 29 in Boston, The American Orthopaedic Association (AOA) and the National Association of Orthopaedic Nurses (NAON) will present two educational/networking events concentrating on secondary fragility fracture prevention.
The Thursday evening Workshop, available only to those attending the Friday Symposium, will convene clinicians with expertise in counseling and treating fragility fracture patients. “This new two-hour workshop provides an additional opportunity to learn more about identifying, assessing, counseling, and treating fragility fracture patients,” said program co-chair Debra Sietsema, PhD, RN. “The Workshop also includes special breakout stations on calcium, FRAX, and the AOA’s ‘Own the Bone’ initiative.”
The all-day Symposium on Friday focuses on how to establish a multidisciplinary secondary fragility fracture program. In addition, the Symposium will include relevant case studies demonstrating how to translate the principles into hospital, private-practice, or clinic settings. “This Symposium is a great opportunity for orthopaedic surgeons and allied health professionals to get the full picture in one day,” said Dr. Sietsema. “Attendees will gain both basic and expanded knowledge to put their programs in place.”
Register by May 15 to receive early-bird pricing for these important events. NAON members and clinicians from enrolled Own the Bone institutions save an additional $50.
It is easy, perhaps even fun (in a cynical way), to discredit clinical guidelines and suggested care pathways for certain orthopaedic diseases. They are often nuanced, may require a significant change to our practice that we find impractical, and may seem to offer little benefit over current practices. Why change when our patients do just fine with how we have always treated them? Well, as Farrow et al. clearly demonstrate in the May 2, 2018 edition of JBJS, we should follow these guidelines and patient care pathways in hip fracture patients ≥50 years old because patients have better outcomes when we do.
The authors found that increased adherence to the Scottish Standards of Care for Hip Fracture Patients (SSCHFP), implemented in Scotland in 2014, led to a >3-fold decrease in patient mortality at 1 month and a 2-fold decrease in mortality at 4 months. High levels of adherence to the SSCHFP also led to shorter hospital stays and decreased odds of discharging patients to high-care settings, such as a skilled nursing facility. This cohort study of data collected from >1,000 patients saw only 8% of the initial population lost to follow-up.
Just as importantly, when the authors ran a multiple regression analysis, they found that no single SSCHFP practice or patient variable was as important as following the total SSCHFP protocol. The authors thus conclude that “the impact of the standards as a whole is greater than the sum of the parts and highlights the importance of a multidisciplinary team approach…” In other words, following the protocol helped improve patient outcomes. Period.
Studies like this by Farrow et al. are important and impactful. Practice guidelines and care criteria are developed with careful attention to the evidence base, but we are just starting to see published data on their effect on outcomes. This makes them difficult to accept because we DO have data (at least anecdotal data) supporting our current practices. It is easier to stick to our known current methods than to adopt new ones, however subtle, that require change and have little accompanying outcomes data. Implementing practice guidelines will always be challenging, but having data such as these showing the power of their effect should help make adoption easier.
Chad A. Krueger, MD
JBJS Deputy Editor for Social Media
Click here to read a press release about this study from the University of Aberdeen.
Risk Reduction Compared with Access to Care: The Trade-Off of Enforcing a BMI Eligibility Criterion for Joint Replacement
Morbidly obese patients with severe osteoarthritis benefit from successful total joint arthroplasty. However, morbid obesity increases the risk of complications. https://bit.ly/2qpfj8w #JBJS
In 1922, Kellogg Speed, MD said in his American College of Surgeons address, “We enter the world under the brim of the pelvis and exit through the neck of the femur.” Since then, it has been repeatedly shown that femoral-neck and intertrochanteric hip fractures are associated with a high mortality rate during the first year following fracture. Now, in the era of widespread hip arthroplasty—and with the consequently increasing rates of periprosthetic fractures near the hip joint—it is relevant to ask whether periprosthetic fractures are associated with an increased risk of mortality similar to that seen after native hip fractures. In the April 4, 2018 issue of The Journal, Boylan et al. use the New York Statewide Planning and Research Cooperative System database to address that question.
The authors reviewed 8 years of native and periprosthetic hip fracture data to determine whether the 1-month, 6-month, and 12-month mortality risk between the two patient cohorts was similar. They found that the 1-month mortality risk in the two groups was similar (3.2% for periprosthetic fractures and 4.6% for native fractures). However, there were significant between-group differences in mortality risk at the 6-month (3.8% for periprosthetic vs 6.5% for native) and 12-month (9.7% vs 15.9%) time points.
This makes clinical sense because, in general, patients experiencing a native hip fracture have lower activity levels and general fitness and higher levels of comorbidity than patients who have received a total hip arthroplasty. Extensive research has resulted in protocols for lowering the risk of mortality associated with native hip fractures, such as surgery within 24 to 48 hours, optimizing medical management through geriatric consultation, and safer and more effective rehabilitation strategies. We need similar research to develop effective perioperative protocols for patients experiencing a periprosthetic fracture, as this study showed that 1 out of 10 of these patients does not survive the first year after sustaining such an injury. I also agree with the authors’ call for more research to identify patients with periprosthetic fractures who are “at risk of worse outcomes at the time of initial presentation to the hospital.”
Marc Swiontkowski, MD
Under one name or another, The Journal of Bone & Joint Surgery has published quality orthopaedic content spanning three centuries. In 1919, our publication was called the Journal of Orthopaedic Surgery, and the first volume of that journal was Volume 1 of what we know today as JBJS.
Thus, the 24 issues we turn out in 2018 will constitute our 100th volume. To help celebrate this milestone, throughout the year we will be spotlighting 100 of the most influential JBJS articles on OrthoBuzz, making the original content openly accessible for a limited time.
Unlike the scientific rigor of Journal content, the selection of this list was not entirely scientific. About half we picked from “JBJS Classics,” which were chosen previously by current and past JBJS Editors-in-Chief and Deputy Editors. We also selected JBJS articles that have been cited more than 1,000 times in other publications, according to Google Scholar search results. Finally, we considered “activity” on the Web of Science and The Journal’s websites.
We hope you enjoy and benefit from reading these groundbreaking articles from JBJS, as we mark our 100th volume. Here are two more:
Autologous Chondrocyte Implantation Compared with Microfracture in the Knee: A Randomized Trial
G Knutsen, L Engebretsen. T C Ludvigsen, J O Drogset, T Grøntvedt, E Solheim, T Strand, S Roberts, V Isaksen, and O Johansen: JBJS, 2004 March; 86 (3): 455
In the first published randomized trial to compare these 2 methods for treating full-thickness cartilage defects, both procedures demonstrated similar clinical results at 2 years of follow-up. The authors also performed arthroscopic and histologic evaluations at 2 years and again found no significant differences between the groups. Since 2004, however, longer-term follow-ups have suggested that autologous chondrocyte implantation is more durable than microfracture (see Clinical Summary on Knee Cartilage Injuries).
The Value of the Tip-Apex Distance in Predicting Failure of Fixation of Peritrochanteric Fractures of the Hip
M R Baumgaertner, S L Curtin, D M Lindskog, and J M Keggi: JBJS, 1995 July; 77 (7): 1058
So-called “cutout” of the lag screw in sliding hip screw fixation of peritrochanteric hip fractures was a recognized cause of failure long before this landmark JBJS study was published in 1995. Twenty-three years later, when value consciousness has repopularized this reliable fixation method (especially in stable fracture patterns), the tip-apex distance as a strong predictor of cutout remains an important surgical consideration.
This tip comes from Fred Nelson, MD, an orthopaedic surgeon in the Department of Orthopedics at Henry Ford Hospital and a clinical associate professor at Wayne State Medical School. Some of Dr. Nelson’s tips go out weekly to more than 3,000 members of the Orthopaedic Research Society (ORS), and all are distributed to more than 30 orthopaedic residency programs. Those not sent to the ORS are periodically reposted in OrthoBuzz with the permission of Dr. Nelson.
It is well-established that total hip arthroplasty (THA) improves quality of life, but how about longevity itself? Cnudde et al.1 attempted to identify associations between THA and lower mortality rates, acknowledging that such rates may also be influenced by diagnostic, patient-related, socioeconomic, and surgical factors.
Using data from the Swedish Hip Arthroplasty Register, the authors identified 131,808 patients who underwent THA between January 1, 1999 and December 31, 2012. Among those patients, 21,755 died by the end of follow-up. Relative survival among the THA patients was compared with age- and sex-matched survival data from the entire Swedish population.
Patients undergoing elective THA had a slightly improved survival rate compared with the general population for approximately 10 years after surgery, but by 12 years, there was no survival-rate difference between patients undergoing THA and the general population (r = 1.01; 95% CI, 0.99-1.02; p = 0.13).
After controlling for other relevant factors and using primary osteoarthritis as the reference diagnosis, the authors found that patients undergoing THA for osteonecrosis of the femoral head, inflammatory arthritis, and secondary osteoarthritis had poorer relative survival.
In addition, married patients and those with higher levels of education fared better. The authors could not pinpoint the reasons for the increase in relative survival among THA patients, but these findings suggest that the explanation is most likely multifactorial.
- Do Patients Live Longer After THA and Is the Relative Survival Diagnosis-specific?Cnudde P, Rolfson O, Timperley AJ, Garland A, Kärrholm J, Garellick G, Nemes S. Clin Orthop Relat Res. 2018 Feb 28. doi: 10.1007/s11999.0000000000000097. [Epub ahead of print]
JBJS Essential Surgical Techniques (EST) is pleased to congratulate the winners of its two Editor’s Choice Awards for 2017:
The award for best surgical-technique article went to Morteza Kalhor, MD; Diego Collado, MD; Michael Leunig, MD; Paulo Rego, MD; and Reinhold Ganz, MD for Recommendations to Reduce Risk of Nerve Injury During Bernese Periacetabular Osteotomy (PAO).
The recipients of the best Key Procedures video award were Jorge Chahla, MD; Gilbert Moatshe, MD; Lars Engebretsen, MD, PhD; and Robert F. LaPrade, MD, PhD for Anatomic Double-Bundle Posterior Cruciate Ligament Reconstruction.