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JBJS Editor’s Choice—Knee Sepsis: Arthroscopic or Open Treatment?

Open vs Arthroscopic Tx for Knee Sepsis.jpegIn the March 15, 2017 issue of The Journal, Johns et al. report results from a Level III cohort study comparing arthroscopic vs open irrigation for control of acute native-knee sepsis. The authors collected information on more than 160 patients with knee sepsis over a 15-year period, which is a large cohort of patients with this relatively unusual clinical problem.

The data show a cumulative success rate of 97% with arthroscopic treatment after 3 irrigations and debridements vs 83% success in the arthrotomy group after the same number of procedures—a clinically important difference. Significantly fewer arthroscopic procedures were required for successful treatment, relative to open procedures, and post-procedure median knee range of motion was significantly greater in the arthroscopic group (90°) than in the open treatment group (70°).

The fact is that arthroscopic instruments allow a greater volume of irrigation fluid to be instilled with better access to the posterior recesses of the knee. With an open arthrotomy, it is more difficult to irrigate with high volumes, and the posterior recesses of the knee are not well accessed. It seems clear that arthroscopic management of acute knee sepsis should be the standard of care for these reasons, as well as because the technique is minimally invasive in terms of soft tissue stripping and incision size.

Treating infections of major-weight bearing joints is following a trend seen in surgical management of many orthopaedic conditions—smaller exposures with use of adjunctive visualization techniques.

Marc Swiontkowski, MD
JBJS Editor-in-Chief

JBJS/JOSPT Webinar–Improving ACL Reconstruction Outcomes

April 4 Webinar Speakers

Anterior cruciate ligament (ACL) reconstruction is a common and predominantly successful surgical intervention.  But are there any specific preoperative patient characteristics or intraoperative surgical decisions that lead to better or worse outcomes? And can understanding brain function changes of patients after ACL reconstruction reveal how to improve postsurgical rehabilitation to further enhance outcomes?

These intriguing and clinically applicable questions will be addressed on Tuesday, April 4, 2017 at 8:00 PM EDT during a complimentary* LIVE webinar, hosted jointly by The Journal of Bone & Joint Surgery (JBJS) and the Journal of Orthopaedic & Sports Physical Therapy (JOSPT).

  • JBJS co-author Kurt Spindler, MD, will discuss findings that identified baseline patient characteristics and intraoperative choices that predicted higher and lower SF-36 Physical Component scores after ACL reconstruction.
  • JOSPT co-author Dustin Grooms, PhD, will share recently published results of a study that employed functional MRI to investigate brain-activation differences between patients who did and did not undergo ACL reconstruction.

Moderated by Kevin Wilk, PT, DPT, a leading authority on rehabilitation of sports injuries, the webinar will include additional insights from expert commentators Eric McCarty, MD, and Karin Silbernagel, PT, PhD. The last 15 minutes will be devoted to a live Q&A session between the audience and panelists.

Seats are limited, so Register Now.

* This webinar is complimentary for those who attend the event live.

Total Joint Arthroplasty: Does One Lead to Another?

TJA and Second TJA.jpegAn estimated 7 million people living in the US have undergone a total joint arthroplasty (TJA), and the demand for total hip arthroplasty (THA) and total knee arthroplasty (TKA) will almost certainly increase during the next 15 years.  But how many people can expect to have an additional TJA after having a first one?

That’s the question Sanders et al. address in their historical cohort study, published in the March 1, 2017 edition of The Journal of Bone & Joint Surgery. They followed more than 4,000 patients who underwent either THA or TKA between 1969 and 2008 to assess the likelihood of those patients undergoing a subsequent, non-revision TJA.

Here’s what they found:

  • Twenty years after an initial THA, the likelihood of a contralateral hip replacement was 29%.
  • Ten years after an initial THA, the likelihood of a contralateral knee replacement was 6%, and the likelihood of an ipsilateral knee replacement was 2% at 20 years.
  • Twenty years after an initial TKA, the likelihood of a contralateral knee replacement was 45%.
  • After an initial TKA, the likelihood of a contralateral hip replacement was 3% at 20 years, and the likelihood of an ipsilateral hip replacement was 2% at 20 years.

In those undergoing an initial THA, younger age was a significant predictor of contralateral hip replacement, and in those undergoing an initial TKA, older age was a predictor of ipsilateral or contralateral hip replacement.

The authors conclude that “patients undergoing [THA] or [TKA] can be informed of a 30% to 45% chance of a surgical procedure in a contralateral cognate joint and about a 5% chance of a surgical procedure in noncognate joints within 20 years of initial arthroplasty.” They caution, however, that these findings may not be generalizable to populations with more racial or socioeconomic diversity than the predominantly Caucasian population they studied.

New Knee Content from JBJS

knee-spotlight-image.pngThe recently launched JBJS Knee Spotlight offers highly relevant and potentially practice-changing knee content from the most trusted source of orthopaedic information.

Here are the five JBJS articles to which you will have full-text access through the Knee Spotlight during the month of March 2017:

  • Improved Accuracy of Component Positioning with Robotic-Assisted Unicompartmental Knee Arthroplasty: Data from a Prospective, Randomized Controlled Study
  • The Effect of Timing of Manipulation Under Anesthesia to Improve Range of Motion and Functional Outcomes Following Total Knee Arthroplasty
  • Anatomic Single-Bundle ACL Reconstruction Is Possible with Use of the Modified Transtibial Technique: A Comparison with the Anteromedial Transportal Technique
  • Autologous Chondrocyte Implantation in the Knee: Mid-Term to Long-Term Results
  • Outcomes of Unicompartmental Knee Arthroplasty After Aseptic Revision to Total Knee Arthroplasty: A Comparative Study of 768 TKAs and 578 UKAs Revised to TKAs from the Norwegian Arthroplasty Register (1994 to 2011)

Knee studies offered on the JBJS Knee Spotlight will be updated monthly, so check the site often.

Visit the JBJS Knee Spotlight website today.

Guest Post: “Telemedicine” for Knee OA Works

telerehabOrthoBuzz occasionally receives posts from guest bloggers. This guest post comes from Chad Krueger, MD, in response to a recent study in the Annals of Internal Medicine.

Few disease processes are as prevalent within the United States as hip and knee osteoarthritis (OA).  While OA is commonly thought to be a disease of older age, the reality is that over half of all individuals with knee arthritis are younger than 65. While some of those individuals will eventually go on to have a knee arthroplasty, before that, most OA patients try various other treatments in an effort to decrease pain and increase function.  Medications such as NSAIDs and others are certainly a part of these treatment efforts, but nonpharmacologic treatments are also widely recommended.

However, as Bennell et al. clearly state in their Annals article, patients face multiple barriers to the implementation of these nonoperative, nonpharmacologic modalities, including cost and transportation to relevant clinical specialists. The authors used these barriers as the rationale for a randomized trial in which an intervention group of knee OA patients received Internet-based educational material, online pain-coping skills training, and videoconferencing with a physiotherapist who provided individualized exercises for each patient. A control group received only the educational material.

At 3 and 9 months, both groups showed improvements in pain and function, but the intervention group had significantly greater improvements than the control group.  More importantly, the people in the intervention group largely adhered to all online programs on their own and were very satisfied with the prescribed treatments, especially the video-based physiotherapy component.

Internet-based health interventions are certainly not new. However, my suspicion is that 20 years from now we will look back and wonder why we did not use them more often. They are self-directed, cost-effective, reproducible, and available to any of the 87% of Americans over the age of 50 who, according to the Pew Research Center, use the Internet. These online interventions require no driving to an office, and patients can easily track their own progress by seeing how many modules they have completed.

While there are certainly limitations to the findings from Benell et al., as an accompanying editorial by Lisa Mandl, MD points out, the study serves as a very strong proof of concept that should be expanded upon. Dr. Mandl herself proclaims that “these results are encouraging and show that ‘telemedicine’ is clearly ready for prime time.”

With the number of ways we “stay connected” always increasing, it seems important for orthopaedists to learn how to use these technologies to benefit our patients.  Doing so may require some adjustments, but the ultimate goal of improving the quality of life for our patients warrants whatever creativity and open-mindedness might be necessary.

Chad Krueger, MD is a military orthopaedic surgeon at Womack Army Medical Center in Fort Bragg, North Carolina.

Smoking Boosts Rate of Reoperation for Infection after TJA

Smoking Image from Nick.jpegHere’s one thing about which medical studies have been nearly unanimous:  Smoking is a health hazard by any measure. In the February 15, 2017 edition of The Journal of Bone & Joint Surgery, Tischler et al. put some hard numbers on the risk of smoking for those undergoing total joint arthroplasty (TJA).

After controlling for confounding factors, the authors of the Level III prognostic study found that:

  • Current smokers have a significantly increased risk of reoperation for infection within 90 days of TJA compared with nonsmokers.
  • The amount one has smoked, regardless of current smoking status, significantly contributed to increased risk of unplanned nonoperative readmission.

In a commentary on the Tischler et al. study, William, G. Hamilton, MD says, “…as physicians, we should work cooperatively with our patients to enhance outcomes by attempting to reduce these modifiable risk factors. We can educate patients and can suggest smoking cessation programs and weight loss regimens that may not only improve the risk profile during the surgical episode, but also improve the patients’ overall health.”

What’s New in Adult Reconstructive Knee Surgery

Every 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, Gwo-Chin Lee, MD, author of the January 18, 2017 Specialty Update on Adult Reconstructive Knee Surgery, selected the five most clinically compelling findings from among the more than 100 studies summarized in the Specialty Update.

Nonoperative Knee OA Treatment

—Weight loss is one popular nonoperative recommendation for treating symptoms of knee osteoarthritis (OA). An analysis of data from  the Osteoarthritis Initiative found that delayed progression of cartilage degeneration, as revealed on MRI and clinical symptoms, positively correlated with BMI reductions >10% over 48 months.1

Total Knee Arthroplasty

—In total knee arthroplasty (TKA), the drive toward producing normal anatomy has led to explorations of alternative alignment paradigms. A prospective randomized study found that small deviations from the traditional mechanical axis (known as kinematic alignment) can be well tolerated and do not lead to decreased survivorship or poorer functional outcomes at short-term follow up.2

—Controversy exists about the optimal method to achieve stemmed implant fixation in revision TKA.  A randomized controlled trial of TKA patients with mild to moderate tibial bone loss found no difference in tibial implant micromotion between cemented and hybrid press-fit stem designs, based on radiostereometric analysis.

Blood Management in TKA

—Minimizing blood loss and transfusions is crucial to minimizing complications after TKA. A randomized, double-blind, placebo-controlled trial found that intra-articular and intravenous administration of tranexamic acid (TXA) was more effective than intravenous TXA alone, without an increased risk of venous thromboembolism (VTE).  However, the optimal regimen for TXA remains undefined.

VTE/PE Prophylaxis

—VTE prophylaxis is essential for all patients undergoing TKA. A risk-stratification study of pulmonary embolism (PE) after elective total joint arthroplasty reported that the incidence of PE within 30 days after either hip or knee replacement was 0.5%. Risk factors associated with PE were age of > 70 years, female sex, and higher BMI. The presence of anemia was protective against PE.  The authors developed an easy-to-use scoring system to determine risk for VTE to help guide chemical prophylaxis.3

References

  1. Gersing AS, Solka M, Joseph GB, Schwaiger BJ, Heilmeier U, Feuerriegel G, Nevitt MC, McCulloch CE,Link TM. Progression of cartilage degeneration and clinical symptoms in obese and overweight individuals is dependent on the amount of weight loss: 48-month data from the Osteoarthritis Initiative. Osteoarthritis Cartilage. 2016 Jul;24(7):1126-34. Epub 2016 Jan 30.
  2. Calliess T, Bauer K, Stukenborg-Colsman C, Windhagen H, Budde S, Ettinger M. PSI kinematic versus non-PSI mechanical alignment in total knee arthroplasty: a prospective, randomized study. Knee Surg Sports Traumatol Arthrosc. 2016 Apr 27. [Epub ahead of print]
  3. Bohl DD, Maltenfort MG, Huang R, Parvizi J, Lieberman JR, Della Valle CJ. Development and validation of a risk stratification system for pulmonary embolism after elective primary total joint arthroplasty. J Arthroplasty. 2016 Sep;31(9)(Suppl):187-91. Epub 2016 Mar 17.

 

New Knee Content from JBJS

knee-spotlight-image.pngThe recently launched JBJS Knee Spotlight offers highly relevant and potentially practice-changing knee content from the most trusted source of orthopaedic information.

Here are the five JBJS articles to which you will have full-text access through the Knee Spotlight during the month of February 2017:

  • Comparison of Highly Cross-Linked and Conventional Polyethylene in Posterior Cruciate-Substituting Total Knee Arthroplasty in the Same Patients

  • What’s New in Adult Reconstructive Knee Surgery

  • Hinged External Fixation in the Treatment of Knee Dislocations: A Prospective Randomized Study

  • A Randomized, Controlled, Prospective Study Evaluating the Effect of Patellar Eversion on Functional Outcomes in Primary Total Knee Arthroplasty

  • Comparison of Functional Outcome Measures After ACL Reconstruction in Competitive Soccer Players: A Randomized Trial

Knee studies offered on the JBJS Knee Spotlight will be updated monthly, so check the site often.

Visit the JBJS Knee Spotlight website today.

JBJS Editor’s Choice: Biomechanics Alone or Biomechanics + UKA for Painful Varus Knees?

UKA vs PTO Survivorship.gifIn the January 18, 2017 issue of JBJS, Krych et al. report on early and mid-term results of the two most common surgical procedures to help patients 55 years old and younger with varus knees and medial compartment osteoarthritis: unicompartmental knee arthroplasty (UKA) and proximal tibial osteotomy (PTO). PTO realigns the knee’s biomechanics by moving the weight-bearing line laterally toward the more normal side of the knee. UKA corrects the biomechanical issue and removes and resurfaces damaged tissue.

In this comparative cohort study of 240 patients between 18 and 55 years old, patients receiving UKA had better functional scores and reached a higher activity level early after surgery. UKA survivorship (defined as avoiding revision to total knee arthroplasty [TKA]) was 94% at an average of 5.8 years, while PTO survivorship was 77% at an average of 7.2 years.

The functional outcomes should come as no surprise, seeing as arthroplasty replaces/denervates the subchondral bone in the medial compartment, while also correcting the alignment issue. A reasonable trauma-related analog to this can be seen with total hip arthroplasty providing generally better functional outcomes for displaced femoral neck fractures than internal fixation because the latter approach does not anatomically restore hip biomechanics. In both those cases, the mechanics of a weight-bearing joint are maintained/improved without relying on bone to heal. In contrast, with PTO and other bone and joint “preservation” approaches, the natural mechanics are altered.

However, I do not think we should extend this argument beyond what these data from Krych et al. provide. The mean length of follow-up in the UKA group was only 5.8 years. We need 20- to 30-year results in that group so we can truly understand the risk of further arthroplasty revision, polyethylene replacement, periprosthetic fracture, etc. I therefore truly hope to see follow-up reporting in a decade on this cohort of patients.

We must also recognize that these patients were selected for a surgical intervention based on their functional demand. The baseline characteristics of both groups suggest that those who had higher loading “habits” received an osteotomy.

Marc Swiontkowski, MD
JBJS Editor-in-Chief

Long-Term Opioid Use Before TKA Raises Risk of Revision

Opioid and TKA Revision.gifGiven the prevalence of opioid prescriptions, many patients present for total knee arthroplasty (TKA) having been on long-term opioid therapy. In the January 4, 2017 edition of The Journal of Bone & Joint Surgery, Ben-Ari et al. determined that patients taking opiate medications for more than three months prior to their TKA were significantly more likely than non-users of opioids to undergo revision surgery within a year after the index procedure.

Among the more than 32,000 TKA patients from Veterans Affairs (VA) databases included in the study, nearly 40% were long-term opioid users prior to surgery. Despite that high percentage, the authors found that chronic kidney disease was the leading risk factor for knee revision among the relevant variables they examined. And even though the authors used a sophisticated natural language/machine-learning tool to analyze postoperative notes, they found no association between long-term opioid use and the etiology of the revisions.

In a commentary accompanying the study, Michael Reich, MD and Richard Walker, MD, note that the study’s very specific VA demographic (94% male) may hamper the generalizability of the findings, especially because most TKAs are currently performed in women. Nevertheless, the commentators conclude that:

  • “The study illuminates the value in limiting opioid use during the nonoperative treatment of patients with knee arthritis.”
  • “Patients who are taking opioids when they present for TKA could reasonably be encouraged to decrease opioid use during preoperative preparation.”
  • “Preoperative use of opioids should be considered among modifiable risk factors and comorbidities when deciding whether to perform TKA.”