What’s New in Musculoskeletal Infection 2018

PPI Image for O'BuzzEvery month, JBJS publishes a Specialty Update—a review of the most pertinent and impactful studies published in the orthopaedic literature during the previous year in 13 subspecialties. Click here for a collection of all OrthoBuzz Specialty Update summaries.

This month, Arvind Nana, MD, and his co-authors of the July 18, 2018 Specialty Update on Musculoskeletal Infection, selected the most clinically compelling findings from among the more than 130 studies summarized in the Specialty Update.

CDC Guidelines on Surgical Site Infection (SSI) Prevention

–The most provocative recommendation in the CDC SSI Prevention Guidelines,1 released in 2017, was to encourage administration of parenteral antimicrobial prophylaxis prior to surgery so that a bactericidal concentration is established in the tissue and serum when the incision is made. Postoperatively, the CDC recommended that antimicrobial prophylaxis not be administered in clean and clean-contaminated procedures after incision closure, even if a drain is present.

Treating Periprosthetic Infection

–When performing debridement to treat a periprosthetic joint infection, dilute methylene blue (0.1%) applied to the tissue prior to debridement (with removal of excess dye) may help surgeons visualize devitalized tissue (biofilm) that should be debrided at the time of infection.2,3

Wound Closure

–Two Level-I studies showed that specific wound-closure techniques can improve incisional perfusion. This was seen in the setting of ankle fracture with the Allgower-Donati suture technique4 and in elective total knee arthroplasty with a running subcuticular closure5.

Antimicrobial Prophylaxis

–Two studies reported on the microbiological impact of locally applied vancomycin powder.6,7  For patients who developed infections after surgery despite the application of vancomycin powder, a greater frequency of gram-negative organisms was identified, highlighting the importance of obtaining specimens for culture.

Hand Infections

–Atypical hand infections caused by Mycobacterium tuberculosis, non-tuberculous mycobacterium, and fungi are uncommon, making high-level clinical trials unrealistic.  But these atypical infections are frequent enough that multiple cases are reported, drawing attention to the need for awareness of their clinical presentation,8 even in immunocompetent patients,9 and the need for understanding that cultures should be sent when suspicion is high, even if there is purulence consistent with a typical bacterial infection.10

References

  1. Berrios-Torres SI, Umscheid CA, Bratzler DW, Leas B, Stone EC, Kelz RR, Reinke CE, Morgan S, Solomkin JS, Mazuski JE, Dellinger EP, Itani KMF, Berbari EF, Segreti J, Parvizi J, Blanchard J, Allen G, Kluytmans JAJW, Donlan R, Schecter WP; Healthcare Infection Control Practices Advisory Committee. Centers for Disease Control and Prevention guideline for the prevention of surgical site infection, 2017. JAMA Surg. 2017 Aug 1;152(8):784-91.
  2. Shaw JD, Miller S, Plourde A, Shaw DL, Wustrack R, Hansen EN. Methylene blue guided debridement as an intraoperative adjunct for the surgical treatment of periprosthetic joint infection. J Arthroplasty. 2017 Dec;32(12):3718-23.
  3. Parry JA, Karau MJ, Kakar S, Hanssen AD, Patel R, Abdel MP. Disclosing agents for the intraoperative identification of biofilms on orthopedic implants. J Arthroplasty. 2017 Aug;32(8):2501-4.
  4. Shannon SF, Houdek MT,Wyles CC, Yuan BJ, CrossWW3rd, Cass JR, Sems SA. Allgower-Donati versus vertical mattress suture technique impact on perfusion in ankle fracture surgery: a randomized clinical trial using intraoperative angiography.  J Orthop Trauma. 2017 Feb;31(2):97-102.
  5. Wyles CC, Jacobson SR, Houdek MT, Larson DR, Taunton MJ, Sim FH, Sierra RJ, Trousdale RT. The Chitranjan Ranawat Award: running subcuticular closure enables the most robust perfusion after TKA: a randomized clinical trial. Clin Orthop Relat Res. 2016 Jan;474(1):47-56.
  6. Adogwa O, Elsamadicy AA, Sergesketter A, Vuong VD, Mehta AI, Vasquez RA, Cheng J, Bagley CA, Karikari IO. Prophylactic use of intraoperative vancomycin powder and postoperative infection: an analysis of microbiological patterns in 1200 consecutive surgical cases. J Neurosurg Spine. 2017 Sep;27(3):328-34. Epub 2017 Jun 30.
  7. Chotai S, Wright PW, Hale AT, Jones WA, McGirt MJ, Patt JC, Devin CJ. Does intrawound vancomycin application during spine surgery create vancomycin-resistant organism? Neurosurgery. 2017 May 1;80(5):746-53.
  8. Lopez M, Croley J, Murphy KD. Atypical mycobacterial infections of the upper extremity: becoming more atypical? Hand (N Y). 2017 Mar;12(2):188-92. Epub 2016 Jul.
  9. Sotello D, Garner HW, Heckman MG, Diehl NN, Murray PM, Alvarez S. Nontuberculous mycobacterial infections of the upper extremity: 15-year experience at a tertiary care medical center. J Hand Surg Am. 2017 Dec 6:S0363-5023(16)30908-X. Epub 2017 Dec 6
  10. Kazmers NH, Fryhofer GW, Gittings D, Bozentka DJ, Steinberg DR, Gray BL. Acute deep infections of the upper extremity: the utility of obtaining atypical cultures in the presence of purulence. J Hand Surg Am. 2017 Aug;42(8):663.e1-8. Epub 2017 May 25.

Journal Club Grant Brings Bhandari to UChicago

Bhandari Head ShotEditor’s Note: The Journal of Bone and Joint Surgery’s Robert Bucholz Resident Journal Club Grant provides selected orthopaedic surgery residency programs with funds that facilitate career-long skills in evaluating orthopaedic literature and its impact on clinical decision-making. The Journal is always interested in hearing how those funds have been used to enhance orthopaedic education. Here, Michael Perrone, MD describes how the University of Chicago’s Department of Orthopaedic Surgery and Rehabilitation Medicine used its grant this past academic year.

Our residency hosted Dr. Mohit Bhandari for two days. Dr. Bhandari is widely recognized as the world’s foremost authority in the translation of orthopaedic research into clinical practice. On the first day, he joined us for dinner at a local Chicago pizzeria, where we had a “Deep Dish-cussion” about several landmark articles within the orthopaedic literature. He provided his insights on the design, merits, and limitations of each paper, while also discussing each study’s clinical impact. Both residents and faculty alike found the discussion enlightening and educational.

The following morning, Dr. Bhandari delivered Grand Rounds to the entire department. His talk, “Fear Less, Do More,” gave us an inside look at the trials and tribulations of conducting large, multicenter studies and bringing them to publication. Throughout the talk, he encouraged residents and faculty to be ambitious in their pursuit of research and evidence-based practice.

There are few people with more experience or expertise within orthopaedic research than Dr. Bhandari, and his visit to our residency program was inspirational and enlightening. Such an experience would not have been possible without the generous support from JBJS.

Michael Perrone, MD
PGY-5
University of Chicago

BOG Fracture-Risk Score Combines DNA Info with Physiological Factors

Fracture Risk Image for OBuzzThis post 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. 

During childhood and adulthood, we often put ourselves at risk for future fractures based on our activity, diet, and social habits. Many factors affect the risk of both stress fractures in younger people and fragility fractures later in life. Everyone—but especially athletes and active-duty military personnel—could benefit from an early heads-up regarding their genetic and phenotypic predisposition to stress fractures. Later in life, the FRAX index is a very useful multifactor risk score, but it is usually calculated only after a sentinel event, such as a fragility fracture.

Ultrasound is a readily available and inexpensive way to obtain an estimated heel bone mineral density (eBMD). Many common genetic variants contribute to the genetic basis for the eBMD phenotype. These variants are most commonly characterized by single nucleotide polymorphisms (SNPs, pronounced “snips”). Stanford researcher Stuart Kim developed the BMD Osteoporosis Genetic (BOG) risk score by combining 22,886 SNPs with data on height, weight, sex, and age.1 The correlation between actual eBMD and the BOG algorithm was 0.496, which was higher than the correlations achieved using the 22,886 genetic predictors or the four covariates alone.

Individuals with low BOG scores had a 17.4-fold increased risk for osteoporosis compared to those with the median BOG score. Low BOG scores were also associated with a 1.9-fold higher risk for bone fractures compared to median BOG values. However, the algorithm’s ability to discriminate cases from controls in the overall population was modest. The receiver operator area under the curve for predicting osteoporosis or fracture by the BOG algorithm was 0.78 and 0.57, respectively.

Although the effect of an individual SNP may be inconsequential, the cumulative effect from many SNPs can be large. The author stated that “an algorithm such as the BOG risk score might be useful to screen the general population…to identify individuals that warrant closer examination, such as BMD measurement via DXA [dual-energy X-ray absorptiometry].”

Reference

  1. Kim SK. Identification of 613 new loci associated with heel bone mineral density and a polygenic risk score for bone mineral density, osteoporosis and fracture. PLoS One. 2018 Jul 26;13(7):e0200785. doi: 10.1371/journal.pone.0200785. eCollection 2018. PMID: 30048462

JBJS 100: Talar Neck Fractures, Knee Cartilage Repair

JBJS 100Under 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 full-text 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:

Fractures of the Neck of the Talus
L G Hawkins: JBJS, 1970 July; 52 (5): 991
This article, richly illustrated with radiographs, reports on >1-year results from 43 patients treated after sustaining a vertical fracture of the neck of the talus. Hawkins introduced a 3-group classification system based on the initial radiographic appearance of the fracture, and he provided an in-depth discussion of the complication of avascular necrosis.

Autologous Chondrocyte Implantation and Osteochondral Cylinder Transplantation in Cartilage Repair of the Knee Joint
U Horas, D Pelinkovic, G Herr, T Aigner, R Schnettler: JBJS, 2003 February; 85 (2): 185
In the 15 years since this paper appeared in JBJS, nearly 800 articles have been published that have “autologous chondrocyte implantation” (ACI) in their title. This study—replete with histologic, biopsy-specimen, and electron microscopy images—compared 2-year results among 40 patients who had received either ACI or autologous osteochondral transplants for knee cartilage defects. Both treatments decreased symptoms, but the authors concluded that “the improvement provided by the [ACI] lagged behind that provided by the osteochondral cylinder transplantation.” For more current information on these cartilage-repair techniques, see the JBJS Clinical Summary on Knee Cartilage Injuries.

Getting to the Core of Bone Marrow Lesions

Bone Marrow Lesion for OBuzzThis post 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. 

The terms “bone marrow edema,” “bone marrow lesion” (BML), and “bone bruise” are often used interchangeably to refer to areas in cancellous bone that have hyperintense marrow signal in fluid-sensitive, fat-suppressed MRI sequences. Although most commonly observed in knee MRIs, BMLs can be seen in a variety of joints. In the hip, they are seen in transient osteoporosis and rapid-onset osteoarthritis. The term “bone bruise” is often specifically applied in the setting of an injury, such as lateral tibial plateau hyperintense changes that are seen after an anterior cruciate ligament rupture.

In the setting of knee osteoarthritis, BMLs are a response to degeneration of menisci, articular cartilage, synovium, or bone itself. One of the mechanisms associated with BMLs seems to be secondary to circulatory response and bone turnover. In one study covered in a 2017 review article1, patients with OA and associated BMLs were randomized to receive the bone antiresorptive agent zoledronic acid (ZA) or placebo. At 6 months, VAS pain scores in the ZA group were reduced by ZA, the reduction in BML area was greater in the ZA group than in the placebo group, and a greater proportion in the ZA group achieved a clinically significant reduction in BML size (39% vs. 18%, p <0.044). A larger study is planned to further define the relationship between reduction in BML size and pain scores.

Regarding “crosstalk” between subchondral bone and articular cartilage in joint disease, recent data suggest that numerous canals and porosities connect the bone to cartilage at the interface. Treatment of the bone compartment with antiresorptives and anti-TGF-β at specific early time points has been shown to have chondroprotective effects in animal models. Additionally, one study identified s14-3-3ε, a short extracellular protein, as a mediator critical in the communication between subchondral bone and cartilage in OA. This may prove to be a potential target for therapeutic or prognostic use.

Numerous articles have outlined the abundance of trabecular microfractures seen in areas where BMLs are present. A commonly held hypothesis is that resorption cavities caused by bone remodeling can act as stress concentrations, promoting further microdamage and leading to a cycle of damage-remodeling-damage. Some individuals may be more prone to rapid bone turnover and thus more prone to developing bone edema.

When your clinical attention is directed to BMLs, their shape and extent may influence nonsurgical treatment decisions. Conservative management may be directed by a better understanding of how BMLs contribute to pain and OA progression.

Reference

  1. Alliston T, Hernandez CJ, Findlay DM, Felson DT, Kennedy OD. Bone marrow lesions in osteoarthritis: What lies beneath. J Orthop Res. 2017 Dec 21. doi: 10.1002/jor.23844. [Epub ahead of print] PMID: 29266428

Properly Selected Patients with Cerebral Palsy Benefit from Upper-Extremity Surgery

CP Image for OBuzzThe orthopaedic community has been abuzz lately with conversations about the value of interdisciplinary teamwork among clinicians and shared decision-making between patients and clinicians. The positive results of both those approaches, implemented with children and adolescents who have cerebral palsy (CP), are revealed in a clinical cohort study by Louwers et al. in the August 15, 2018 JBJS.

The authors engaged 66 patients with CP in a comprehensive, multidisciplinary screening process and shared decision-making to determine each patient’s suitability for upper-extremity surgery. Forty-four patients were deemed eligible for surgery and 39 (mean age of 15 years) underwent surgery.  Seven types of surgery were performed, depending on each patient’s predetermined goals, values, and preferences.  Seventy-seven percent of patients had surgery that consisted of flexor carpi ulnaris tendon release or transfer and adductor pollicis muscle slide plus extensor pollicis longus rerouting.

The authors itemize the preoperative and postoperative assessment tools used in the study and describe them as “suitable for selecting patients for upper-extremity surgery and for evaluating the effect of that surgery.”

The bottom line: All outcomes improved significantly after patient-specific upper-extremity surgery in those deemed suitable for it and who opted for surgery after the shared decision-making process. Most of the patients experienced clinically relevant improvement in their functional and cosmetic goals and in manual performance 9 months after their operation.

The two patients who chose nonsurgical treatment after going through the assessment and shared decision-making process did so due to a lack of motivation for the intensive postoperative rehabilitation, which began with upper-limb immobilization for 5 to 6 weeks, followed by a program customized for each patient by his or her rehabilitation physician and occupational therapist.

Structural Allografts Can Work for Acetabular Defects in THA

Structural Allograft for OBuzzAllograft bone is used often in orthopaedic surgery. However, the use of structural allografts to address large acetabular defects in total hip arthroplasty (THA) is not common. But it may become more so in light of the study by Butscheidt et al. in the August 15, 2018 issue of JBJS. The authors add to our knowledge about these relatively rare procedures by evaluating the incorporation of structural acetabular allografts into host bone among 13 complete pelvic explants containing allograft that had been in place for a mean of 13 years.

Using sophisticated imaging and histological techniques, the authors found that in 10 out of the 13 specimens retrieved, 100% of the interface was characterized by direct contact and additional overlap of the allograft bone and the host bone. The remaining 3 allografts showed direct contact along 25% to 80% of the interface.  The authors found no correlation between ingrowth of the host bone into the allograft and the amount of time the allograft had spent in situ, leading them to surmise that “a large proportion of the incorporation process may be completed within the first weeks.”

Large, structural allografts are not commonly used for acetabular reconstructions, as most surgeons seem to favor other options.  (See the JBJS Clinical Summary on “Managing Acetabular Defects in Hip Arthroplasty.”) While a postmortem study of 13 cases may not be “practice-changing,“ the Butscheidt et al. analysis does provide some detailed clarity as to what surgeons can expect from these large allograft reconstructions in terms of incorporation with host bone. Obviously, one limitation of this study is that structural allografts that never incorporated with the host bone probably failed early and would not be available for analysis in a long-follow-up retrieval study.

Chad A. Krueger, MD
JBJS Deputy Editor for Social Media

New Findings in Muscle Injury—An Under-Researched Subject

Periostin for OBuzzThe goal of orthopaedic surgery is to help the entire musculoskeletal system function in harmony, but the preponderance of orthopaedic research focuses on the skeletal system instead of muscles and tendons. Bone is the only organ that can heal by regenerating tissue that is usually just as effective as the original structure. Consequently, we have focused on developing systems to hold bone intact as it heals so that postinjury function is maximized. Decades have been spent understanding the critical biologic pathways of bone healing and developing implantable, pharmacologic, and cell-based therapies to optimize it.

However, we sometimes overlook the fact that the skeleton can’t move without muscles. Only a few researchers have devoted their careers to understanding skeletal muscle’s response to injury and approaches to enhance muscle recovery after disuse and injury. In the August 15, 2018 issue of The Journal, Hara et al. report on experiments with the protein periostin in mice. Periostin is involved with the process of muscle fibrosis, during which fibroblasts proliferate in the injured area of the muscle and create “scar tissue” that eventually inhibits muscle function.

In one experiment, the authors found that “knockout” mice without the gene that encodes for periostin had improved recovery in a lacerated gastrocnemius muscle, less fibrosis in the muscle, and a significantly reduced number of infiltrating fibroblasts than “wild” mice with the same induced injury. In a similar experiment, they found reduced muscle fibrosis in injured muscles of mice whose production of periostin was neutralized by an antibody injected into the injured muscle. Although a sharp injury to muscle (the laceration model used in these mouse experiments) is not a common clinical scenario in patients seen by orthopaedists, the Hara et al. study represents a step forward in understanding muscle response to injury.

While these findings need to be replicated and then translated into clinical applications for humans, they shed new light on the importance of preventing periostin-induced fibroblast migration after skeletal muscle injury. This research hints at a potential therapeutic strategy to enhance muscle’s functional recovery, which is the most sought-after outcome for patients.

The clinical sports and orthopaedic communities are in need of approaches to limit scarring and atrophy in the setting of muscle disuse and injury. Any of us who unavoidably injure muscle during surgical approaches to bones and joints or for graft harvests and other procedures should be heartened by these findings. It is my hope that more early-career researchers will focus on the first half of the term “musculoskeletal” to advance therapeutic approaches to problems that impact function to a much more permanent degree than do most bone injuries.

Marc Swiontkowski, MD
JBJS Editor-in-Chief

JBJS 100: Harris Hip Score, Clavicle Fractures

JBJS 100Under 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 full-text 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:

Traumatic Arthritis of the Hip after Dislocation and Acetabular Fractures—Treatment by Mold Arthroplasty: An End-Result Study Using a New Method of Result Evaluation
W H Harris: JBJS, 1969 June; 51 (4): 737
The most lasting legacy from this classic 1969 article from William Harris is the author’s proposed hip score. A “single, reliable figure” designed to be equally applicable to different hip problems and different treatments, the Harris Hip Score is still used worldwide today in routine evaluations before and after hip arthroplasty. Not surprisingly, this article remains the most frequently cited paper in the hip arthroplasty literature.

Nonoperative Treatment Compared with Plate Fixation of Displaced Midshaft Clavicular Fractures
Canadian Orthopaedic Trauma Society: JBJS, 2007 January; 89 (1): 1
Amid the ongoing debate about whether to operate on which type of clavicle fractures, this multicenter, randomized clinical trial stands out for its rigorous design and focus on patient-oriented outcomes. Local irritation and unsightly prominence from hardware notwithstanding, these findings support primary plate fixation of completely displaced midshaft clavicle fractures in active adult patients.

New Frontiers in Journal Clubs

Journal Club for OBuzzDepending on which historical account you read, journal clubs have been a staple of medical education since around 1875.  Still ubiquitous within medical education today, journal clubs help educators and students alike stay current on medical literature, provide a vehicle for teaching how to critically appraise medical studies, and convene a forum in which respectful debate can occur among colleagues.  Journal clubs constitute a medical-education practice that almost no one questions, probably because they are so effective.

But that doesn’t mean journal clubs can’t be improved. As the September 30, 2018 deadline approaches to submit applications for the JBJS Robert Bucholz Journal Club Grant Program (click here for the application form), I encourage medical-education leaders to envision new ways in which journal clubs could further orthopaedic education. That might include various iterations of “virtual” journal clubs over the internet. For example, the Journal of Hand Surgery recently hosted a journal club on Twitter.  Another intriguing possibility would be to invite authors of journal articles with conflicting conclusions about the same research question to discuss their findings in a point/counterpoint format over teleconference. (Today’s teleconferencing platforms are not hard to set up, are relatively low-cost, and could broaden journal-club participation to anyone with a suitable device and a high-speed internet connection.)

The traditional face-to-face journal club provides many unique benefits, but creating new, innovative platforms for using departmental or grant-based journal-club funds could increase their impact and help ensure the sustainability of these educational programs. It will also be important for everyone to share their experiences with alternative journal-club formats. It behooves the orthopaedic community to continually envision how to integrate the journal-club component of medical education into new technologies as they evolve.

Chad A. Krueger, MD
JBJS Deputy Editor for Social Media