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More Data on Outpatient vs Inpatient Joint Replacement

TKA for OBuzzIn addition to the Pearl Diver-based retrospective study by Arshi et al. on one-year complications after outpatient knee replacement, the December 6, 2017 issue of JBJS contains a NSQIP-based retrospective study by Basques et al. that compares 30-day adverse events and readmissions among 1,236 patients who underwent same-day-discharge hip or knee (total or unicompartmental) arthroplasty with an equal number of propensity score-matched patients who were discharged at least 1 calendar day after the procedure.

When analyzing all three procedures together, the authors found no overall between-group differences in the rates of any adverse event (severe or minor) or readmission. However, when authors analyzed individual adverse events, the same-day group had decreased thromboembolic events and increased 30-day reoperations compared to inpatients. Analysis of individual procedures revealed an increased 30-day reoperation rate for same-day total knee arthroplasty (TKA), compared with inpatient TKA. Overall, infection was the most common reason for reoperation and readmission following same-day procedures.

As with the Arshi et al. study, the limitations of the database prevented these authors from accounting for physician or hospital volume. However, they did identify several preoperative patient characteristics that increased the risk of 30-day readmission among same-day patients, and from those findings Basques et al. concluded that “obese patients, older patients [≥85 years of age], and those with diabetes mellitus may not be appropriate candidates for same-day procedures.”

Outpatient Knee Replacement Complications: How Important Are They?

Outpatient TKA for OBuzzIn the December 6, 2017 issue of The Journal, Arshi et al. report on a detailed analysis of a large administrative database, looking specifically at one-year complications associated with outpatient versus standard inpatient knee replacement. This type of analysis is crucial because of the rapidly growing interest in outpatient joint replacement among patients, payers, and the orthopaedic community.

The data convince me that these outpatient procedures should proceed, but with a little more caution. Although the absolute complication rates in both surgical settings were very low, after adjusting for age, sex, and comorbidities, the authors found a higher relative risk of several surgical and medical complications among outpatients—including component failure, infection, knee stiffness requiring manipulation under anesthesia, and deep vein thrombosis.

One important element that is lacking in this analysis is adjustment for surgeon/hospital volume. We know from important work by Katz and others that patients managed at centers and by surgeons with greater volumes of total knee replacement have lower risks of perioperative adverse events.

These results from Arshi et al. are definitely not a call to stop the expansion of outpatient joint replacement protocols. Instead, I think this study should prompt every joint-replacement center to analyze its risk-adjusted inpatient and outpatient outcomes—and to ensure, as these authors emphasize, that outpatients receive the same level of attention to rehabilitation, antibiotic administration, and thromboprophylaxis as inpatients.

Enhancing outpatient knee-replacement protocols will serve local communities well, and the nationwide orthopaedic community will receive further confirmation that outpatient joint replacement is a move in the right direction.

Marc Swiontkowski, MD
JBJS Editor-in-Chief

Webinar on Dec. 13—Patient Satisfaction After ACL Surgery

webinar speakersAn estimated 300,000 ACL surgeries are performed in the US annually, at an estimated cost of up to $1 billion, but we still have many unanswered questions about patient satisfaction after these procedures. Among them:

  • Does the cost of postoperative physical therapy affect patient satisfaction?
  • What are the rates and predictors of return to play after ACL reconstruction? Does graft choice play a role?
  • What is the relationship between return to play and patient satisfaction?

On Wednesday, December 13, 2017 at 8:00 PM EST, the Journal of Orthopaedic & Sports Physical Therapy (JOSPT) and The Journal of Bone & Joint Surgery (JBJS) will host a complimentary* LIVE webinar that addresses these and other important questions.

JOSPT co-author Caitlin J. Miller, PT, DPT and JBJS co-author Benedict U. Nwachukwu, MDMBA, will discuss findings from their respective studies, and the webinar will include additional insights from Mark V. Paterno, PT, PhD, MBA, SCS, ATC, and Elizabeth Matzkin, MD. Moderated by Tara Jo ManalPT, DPT, OCS, SCS, FAPTA, the webinar will conclude with a live Q&A session between the audience and panelists.

Seats are limited so REGISTER NOW.

*All registrants will have free access to the webinar for 24 hours following the live broadcast.

Patient Satisfaction After ACL Reconstruction—Dec. 13 Webinar

webinar speakersWe still have many unanswered questions about patient satisfaction after anterior cruciate ligament (ACL) reconstruction.

  • Do specific patient populations benefit from more or fewer physical therapy (PT) visits?
  • Does the cost of PT affect patient satisfaction?
  • Should patients be classified by factors beyond their medical diagnoses to achieve the best outcomes while minimizing costs?
  • What are the rates and predictors of return to play after ACL reconstruction? Does graft choice play a role?
  • What is the relationship between return to play and patient satisfaction?

On Wednesday, December 13, 2017 at 8:00 PM EST, the Journal of Orthopaedic & Sports Physical Therapy (JOSPT) and The Journal of Bone & Joint Surgery (JBJS) will host a complimentary* LIVE webinar that addresses these important and clinically applicable questions.

JOSPT co-author Caitlin J. Miller, PT, DPT, will share the results of a retrospective cohort study examining the relationship between patient demographics, number of physical therapy visits, and the cost of postoperative interventions with revision rates and patient-reported outcomes following primary ACL reconstruction.

JBJS co-author Benedict U. Nawachukwu, MD, MBA, will discuss findings from a study  of return to play and patient satisfaction among athletes following ACL reconstruction. This study also explores the efficacy of patellar tendon autografts and the preinjury impact of certain sports.

Moderated by Tara Jo Manal, PT, DPT, OCS, SCS, FAPTA, a leading authority on the spine and the knee, the webinar will include additional insights from expert commentators Mark V. Paterno, PT, PhD, MBA, SCS, ATC, and Elizabeth Matzkin, MD. The last 15 minutes will be devoted to a live Q&A session between the audience and panelists.

Seats are limited so REGISTER NOW.

*All registrants will have free access to the webinar for 24 hours following the live broadcast.

Fructosamine Bests HbA1c for Preop Glycemic Screening

Fructosamine for OBuzzPatients with diabetes have an increased risk of postoperative complications following total joint arthroplasty (TJA). Additionally, perioperative hyperglycemia has been identified as a common and independent risk factor for periprosthetic joint infection, even among patients without diabetes. Therefore, knowing a patient’s glycemic status prior to surgery is very helpful.

In the November 15, 2017 edition of The Journal of Bone & Joint Surgery, Shohat et al. demonstrate that serum fructosamine, a measure of glycemic control obtainable via a simple and inexpensive blood test, is a good predictor of adverse outcomes among TJA patients—whether or not they have diabetes.

Researchers screened 829 patients undergoing TJA for serum fructosamine and HbA1c—a common measure, levels of which <7% are typically considered good glycemic control. Patients with fructosamine levels ≥292 µmol/L had a significantly higher risk of postoperative deep infection, readmission, and reoperation, while HbA1c levels ≥7% showed no significant correlations with any of those three adverse outcomes. Among the 51 patients who had fructosamine levels ≥292 µmol/L, 39% did not have HbA1c levels ≥7%, and 35% did not have diabetes.

In addition to being more predictive of postsurgical complications than HbA1c, fructosamine is also a more practical measurement. A high HbA1c level during preop screening could mean postponing surgery for 2 to 3 months, while the patient waits to see whether HbA1c levels come down. Fructosamine levels, on the other hand, change within 14 to 21 days, so patients could be reassessed for glycemic control after only 2 or 3 weeks.

While conceding that the ≥292 µmol/L threshold for fructosamine suggested in this study should not be etched in stone, the authors conclude that “fructosamine could serve as the screening marker of choice” for presurgical glycemic assessment. However, because the study did not examine whether correcting fructosamine levels leads to reduced postoperative complications, a prospective clinical trial to answer that question is needed.

High Value Joint Replacements at Physician-Owned Hospitals

H image for OBuzzIn the November 15, 2017 issue of The Journal, Courtney et al. carefully evaluate CMS data to compare TKA and THA costs, complications, and patient satisfaction between physician-owned and non-physician-owned hospitals. The authors used risk-adjusted data when comparing complication scores between the two hospital types, in an attempt to address the oft-rendered claim that surgeons at physician-owned facilities “cherry pick” the healthiest patients and operate on the highest-risk patients in non-physician-owned facilities.

In general, the findings suggest that, for TKA and THA, physician-owned hospitals are associated with lower costs to Medicare, fewer complications and readmissions, and superior patient-satisfaction scores compared with non-physician-owned hospitals. These findings should come as no surprise to readers of The Journal. One fundamental principle of health care finance is that physicians control 70% to 80% of the total cost of care with their direct decisions. When physician incentives are aligned with those related to the facility, the result is better care at lower cost.

Nevertheless, many policymakers remain convinced that physician-owners are completely mercenary and base every decision on maximizing profit margins—even if that includes ordering unnecessary tests, performing unnecessary procedures, or using inferior implants. We need more transparency among physician-owners at local and national levels to address these usually-erroneous assumptions, which are frequently repeated by local non-physician-owned health systems. For example, we should be transparent with the percentage of the margin that ends up in the physician-owner’s pocket. Whatever the “right” percentage is, I believe it should not be the dominant factor in a physician’s total income..

The findings from Courtney et al. should spur further debate on this issue. I am confident that the best outcomes for individual patients and the public result when physicians (and their patients) stay in direct control of decision making regarding care, when surgeons are appropriately motivated to be cost- and outcome-effective, and when we all do our part to care for the under- and uninsured.

Marc Swiontkowski, MD
JBJS Editor-in-Chief

“Phenotype” Redefined in Osteoarthritis Research

Osteoarthritis for BSTOTWThis basic science 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.

Over the decades, the meaning of the term “phenotype” has changed. In the past it was solely applied to inherited disorders and was based on physical appearance or clinical presentation. Similarly, the term “penetrance” was applied to the variations in phenotype severity relative to normal. Over time, it has been found that penetrance is usually a reflection of different mutations for the same gene at different parts of the allele, or a mutation in one of several specific genes that could contribute to a similar phenotype.

Now, both terms have been applied to a variety of genetic and environmental circumstances that may affect physical appearance and function. In osteoarthritis research, the term “phenotype” has increasingly been used to define physical, genetic, environmental, and other variables, both past and present.

The authors of a recent abstract use a modern application for the term phenotype to systematically review the literature for studies using knee characteristics relevant for phenotyping osteoarthritis (OA).1 A comprehensive search was performed limited to observational studies of individuals with symptomatic knee OA that identified phenotypes based on OA characteristics, and then the authors assessed phenotypic association with clinically important outcomes.

Based on their abstract, 34 of 2777 citations were included in a descriptive synthesis of the data. Clinical phenotypes were investigated most frequently, followed by laboratory, imaging, and etiologic phenotypes. Eight studies defined subgroups based on outcome trajectories (pain, function, and radiographic progression). Most studies used a single patient or disease characteristic to identify subgroups, while five included characteristics from multiple domains.

Evidence from multiple studies suggested that pain sensitization, psychological distress, radiographic severity, BMI, muscle strength, inflammation, and comorbidities are associated with clinically distinct phenotypes. Gender, obesity and other metabolic abnormalities, the pattern of cartilage damage, and inflammation may delineate distinct structural phenotypes. However, only a few of the 34 studies reviewed investigated the external validity of the chosen phenotypes or their prospective validity using longitudinal outcomes.

While the authors remarked on the heterogeneity of the data included in studies investigating knee OA phenotypes, they say that the phenotypic characteristics identified in their review could form a classification framework for future studies investigating OA phenotypes.

It should be noted that the FRAX score used to calculate fragility fracture risk could be considered a phenotypically based system, the validation of which is continuing.

Reference

  1. Deveza LA, Melo L, Yamato TP, Mills K, Ravi V, Hunter DJ. Knee osteoarthritis phenotypes and their relevance for outcomes: a systematic review. Osteoarthritis 2017 Aug 25. pii: S1063-4584(17)31156-1. doi: 10.1016/j.joca.2017.08.009. [Epub ahead of print].

With OCA, Don’t Fret About Condyle Matching

OCA for OBuzz

Osteochondral allograft transplantations (OCAs) are becoming a mainstay of treatment for knee-cartilage injuries. To help ensure that the allograft plug is transplanted with <1 mm of step-off from the surrounding recipient cartilage, many surgeons restrict themselves to orthotopic OCAs—matching the graft-recipient condyles in a lateral-to-lateral or medial-to-medial fashion.

However, in the October 4, 2017 issue of The Journal of Bone & Joint Surgery, Wang et al. demonstrated that both orthotopic and non-orthotopic (e.g., lateral condyle-to-medial condyle) OCA resulted in significantly improved outcomes in 77 cases followed for a mean of 4.3 years. The authors found that reoperation rates and pre- and postoperative scores in physical functioning and pain did not differ significantly between the orthotopic (n=50) and non-orthotopic (n=27) groups. These results suggest that condyle-specific matching may not be necessary.

One problem with orthotopic OCA is that 75% of the available allograft is supplied in the form of lateral condyles, while most full-thickness cartilage lesions presenting for treatment occur in the medial condyle. Consequently, surgeon preferences for orthotopic OCA limit the number of available matches and lead to an estimated 13% of available grafts being discarded.

Noting that many factors contribute to successful resurfacing of cartilage defects in the knee, the authors say that “it may be overly simplistic to assume that a conventionally matched orthotopic allograft will ensure a smooth surface contour at the recipient site.” They go on to conclude that “if surgeons forewent condyle-specific matching, more allografts would be readily available, which would shorten wait times, provide fresher grafts with increased chondrocyte viability, and lower procedure costs.”

New Level-I Data on TKA Blood Conservation

TXAMinimizing perioperative blood loss during total knee arthroplasty (TKA) helps curtail the risks and costs of allogeneic blood transfusions. Currently, the most popular pharmacological approach to blood conservation is the antifibrinolytic agent tranexamic acid (TXA). But in a randomized trial published in the October 4, 2017 edition of The Journal of Bone & Joint Surgery, Boese et al. found that a similar and much less expensive compound, epsilon-aminocaproic acid (EACA), performed almost as effectively and just as safely as TXA in patients undergoing unilateral knee replacement.

Although the 98 patients in the study who received TXA averaged less estimated blood loss than the 96 patients who received EACA, no transfusions were required in either group, and there were no statistically significant or clinically relevant between-group differences in the change in hemoglobin levels. On the safety/complication side, there were no statistically significant between-group differences in any measured parameter, including postoperative serum creatinine levels or renal, bleeding, or thrombotic complications. However, there were 3 pulmonary emboli in the EACA group compared with only 1 in the TXA group. While that was not a statistically significant difference, “an observed difference of this magnitude could limit the usefulness of EACA in TKA,” the authors caution.

This study did not compare the current cost of the two compounds, but back in 2012, when the authors’ institution added antifibrinolytics to their blood management program, TXA cost $43/g, compared with $0.20/g for EACA. The cost differential is striking, even when you consider that TXA is at least 7 times more potent than EACA on a molar basis, so less of the former drug is required.

Boese et al. conclude that “TXA does not have superior blood conservation effects or safety profile compared with EACA in TKA,” but they cite a need for future equivalence, superiority, and noninferiority trials with these drugs.

D-Dimer Levels May Help with PJI Diagnoses

D-dimer for OBuzzThe percentage of periprosthetic joint infections (PJIs) among patients requiring revision arthroplasty of the hip and knee is increasing. PJIs have important clinical implications both for revision surgical procedures as well as pre- and postoperative management. Any extra help we can get making a PJI diagnosis outside of the obvious (where the patient presents with a draining wound) would be most welcome.

In the September 6, 2017 issue of The Journal, Shahi et al. present compelling data from a prospective study suggesting that serum D-dimer levels may help diagnose PJI—and thereby help determine the optimal timing of component reimplantation. The authors determined that 850 ng/mL was the optimal threshold value for D-dimer in diagnosing PJI. Moreover, with sensitivity of 89% and specificity of 93%, this test outperformed the widely used ESR and CRP tests, which until now have proven to be the “best” tools we have at our disposal.

Ideally, after these results are confirmed in larger populations of patients undergoing revision arthroplasty, the serum D-dimer test—inexpensive and almost universally available—will be used in all high-volume joint replacement centers. The continued pursuit of diagnostic and treatment methodologies for patients with suspected PJI is definitely warranted, given the increasing number of patients requiring arthroplasty and combined lifetime knee- and hip-replacement revision rates hovering around 10% to 12%. The identification of D-Dimer elevation as a potentially more accurate diagnostic tool than our currently available tests is a welcome contribution.

Marc Swiontkowski, MD
JBJS Editor-in-Chief