This 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.
Early cartilage changes in early-stage osteoarthritis (OA) often exist before symptoms arise. Using MRI, researchers assessed a random sample of 73 subjects, aged 40 to 79 years and without knee pain, for cartilage changes.1 A self-reported BMI at age 25, a current measured BMI, and change in BMI were recorded. Knee cartilage was scored semi-quantitatively (grades 0 to 4) on MRI. In primary analysis, cartilage damage was defined as ≥2 (at least moderate), and in a secondary analysis as ≥3 (severe). Researchers also conducted a sensitivity analysis by dichotomizing current BMI as <25 vs. ≥25. Logistic regression was used to evaluate the association of each BMI variable with prevalent MRI-detected cartilage damage, adjusted for age and sex.
Their abstract states that among the 73 subjects, knee cartilage damage ≥2 and ≥3 was present in 65.4% and 28.7%, respectively. Note the high prevalence. The median current BMI was 26.1, while the median past BMI was 21.6. For cartilage damage ≥2, current BMI had a non-statistically significant odds ratio (OR) of 1.65 per 5-unit increase in BMI (95% CI 0.93-2.92). For cartilage damage ≥3, current BMI showed a trend towards statistical significance with an OR of 1.70 per 5 units (95% CI 0.99-2.92). Past BMI and change in BMI were not significantly associated with cartilage damage. Current BMI ≥ 25 was statistically significantly associated with cartilage damage ≥2 (OR 3.04 [95% CI 1.10-8.42]), but not with damage ≥3 (OR 2.63 [95% CI 0.86-8.03]).
The take-home is that MRI-detected knee cartilage damage is highly prevalent in asymptomatic populations aged 40 to 79 years. There is a trend towards significance in the relationship between rising BMI and cartilage damage severity. (It should be added there are localities where a BMI of 26.1, which is technically in the “overweight” zone, would be considered relatively low.) Although this study lends some support to the relationship between BMI and the pathogenesis of knee cartilage damage in asymptomatic people, the role of BMI in symptomatic OA progression is clearer.
In another study, researchers showed that weight loss over 48 months among obese and overweight individuals is associated with slowed knee cartilage degeneration and improved knee symptoms.2 These results point to a promising approach to disease modification that carries little or no risk.
- Keng A, Sayre EC, Guermazi A, Nicolaou S, Esdaile JM, Thorne A, Singer J, Kopec JA, Cibere J. Association of body mass index with knee cartilage damage in an asymptomatic population-based study. BMC Musculoskelet Disord. 2017 Dec 8;18(1):517. doi: 10.1186/s12891-017-1884-7. PMID: 29221481 PMCID: PMC5723095
- 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. doi: 10.1016/j.joca.2016.01.984. PMID: 26828356 PMCID: PMC4907808
In previous studies, simultaneous bilateral total knee arthroplasty (TKA) in appropriately selected patients has compared favorably with staged bilateral TKA—in terms of both clinical outcomes and cost. In the December 20, 2017 issue of The Journal of Bone & Joint Surgery, Meehan et al. report on a population-based analysis of 90-day and 180-day postoperative knee stiffness requiring manipulation under anesthesia (MUA) in three patient subgroups: those undergoing simultaneous bilateral, unilateral, and staged bilateral TKA. In this retrospective Level-III study, the authors made appropriate methodological adjustments to account for patients who planned a staged bilateral TKA but did not have the second operation.
In terms of cumulative MUA incidence after 90 and 180 days, rates were lowest in the simultaneous bilateral TKA group. After adjusting for relevant risk factors, Meehan et al. found that, after 90 days, the odds ratio (OR) of undergoing MUA after simultaneous bilateral TKA was significantly lower than that for unilateral TKA and staged bilateral TKA. Similar MUA odds were found among the three groups at 180 days.
The authors also identified significant nonsurgical risk factors for MUA at 90 days. Those included younger age, black race, no chronic comorbidities, and normal weight. The 180-day nonsurgical risk factors for MUA were the same as those for 90 days, with two additions—female sex and Hispanic ethnicity.
While Meehan et al. acknowledge that “there is no uniformity to indications for MUA” and that such decisions are “obviously surgeon- and patient-specific,” they nevertheless conclude that patients undergoing simultaneous bilateral TKA had a significantly lower risk of requiring MUA for stiffness than those in the other two TKA groups studied.
Two of the most trusted names in medical and scientific content have joined forces to create the very best in ongoing orthopaedic education. JBJS Clinical Classroom on NEJM Knowledge+ is a state-of-the-art adaptive learning platform that helps you assess the orthopaedic material you know and identify the areas where you need reinforcement.
JBJS Clinical Classroom houses more than 2,800 questions based on learning objectives developed by experts in 10 orthopaedic subspecialties, continually tailoring the experience to your specific learning needs.
For learners—residents, fellows, or board-certified orthopaedists—JBJS Clinical Classroom reinforces clinical skills and boosts your confidence. You can even create personalized subspecialty exams and read relevant “suggested resources” from JBJS and other peer-reviewed references. You can also earn AMA PRA Category 1 Credits TM—and JBJS Clinical Classroom is approved by the ABOS to provide scored and recorded self-assessment examination (SAE) credits for maintenance of certification (MOC). JBJS Clinical Classroom is simply the most efficient and effective way to prepare for initial board certification or MOC exams.
For Residency Program Directors, JBJS Clinical Classroom reports performance data at the individual and program level. Directors can identify at-risk performers and monitor group and individual performance by learning objective and by postgraduate year.
With this special introductory offer, you can purchase a full year of JBJS Clinical Classroom on NEJM Knowledge+—all 10 subspecialty modules—for $479. That’s 20% off the $599 list price.
Hip arthroscopy for labral pathology and cam and pincer impingement has become increasingly established as an effective procedure in the hands of experienced surgeons. However, as with all technically complex orthopaedic procedures, success entails not only sound technique, but also appropriate patient selection, meticulous pre- and intraoperative setup, and appropriate use of intraoperative fluoroscopy. Thankfully, we have a community of leaders in arthroscopy who share and teach these details.
In the December 20, 2017 issue of The Journal, Duchman et al. use the ABOS Part-II exam database to analyze who among recent graduates of orthopaedic residencies is performing hip arthroscopies. Overall, between 2006 and 2015, the authors found that 643 of 6,987 ABOS candidates (9.2%) had performed ≥1 hip arthroscopy; nearly three-quarters of those reported sports-medicine fellowship training. More than two-thirds of candidates performing hip arthroscopy performed ≤5 such procedures; conversely, only 6.5% of those candidates performed 35% of all the hip arthroscopies identified in the database.
The concerning suggestion from these findings is that the increase in hip arthroscopy utilization comes from an increased number of individuals performing the surgery, rather than from an increase in procedure volume among individual surgeons. One question this study does not address is whether there has been an increase in the prevalence of hip pathology that warrants an increased utilization of this procedure. If not, an alternative explanation, which Wennberg et al. posit in the Dartmouth Atlas, is that procedure utilization expands in relationship to the distribution of provider resources and medical opinion in the local community.
I believe that hip arthroscopy is technically challenging and that the quality of the outcome is very likely related to the per-surgeon volume of procedures performed. This makes it incumbent upon all orthopaedists who offer this procedure to actively evaluate their outcomes with validated instruments so the practitioner and her/his patients can objectively understand and discuss what the results are likely to be.
In a commentary on this study, Rupesh Tarwala, MD calls for an outcomes analysis of patients who were treated with hip arthroscopy by ABOS Part-II candidates. I concur completely, and would more specifically ask that the cohort of surgeons evaluated in this study by Duchman et al. collect and report their 1- and 2-year outcomes to The Journal.
Marc Swiontkowski, MD
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, Matthew J. Allen, VetMB, PhD, author of the December 6, 2017 Specialty Update on Musculoskeletal Basic Science, summarized the five most compelling findings from among the more than 60 noteworthy studies summarized in the article.
–Deriving induced pluripotent stem cells (iPSCs) from peripheral blood cells1 rather than from dermal fibroblasts obviates the need for in vitro expansion. This method may also serve to boost interest in the use of commercial cell-based therapies with defined potency that are available off-the-shelf and don’t require separate cell-harvesting procedures.
–The FDA recommends that large-animal models be used to corroborate basic-science findings from small-animal models. Recent work has demonstrated the efficacy of insulin-like growth factor (IGF)-1 in supporting mechanically competent repair tissue following chondrocyte implantation in a pig model.2
–Infection, especially from organisms that have developed antimicrobial resistance and/or that produce biofilms, continues to pose a challenging problem for orthopaedic surgeons. To provide a more rational and stratified approach to managing these complex cases, Getzlaf et al. recommend the use of a multidisciplinary approach in which patient-specific information about individual microorganisms is combined with detailed understandings of the vulnerabilities of candidate bacterial species.3
–There is a resurgence of interest in the role of subclinical infection in the etiopathogenesis of aseptic loosening. At the same time, molecular diagnostic methods for microbial infection are moving forward.4 Such methods may serve to highlight the relevance of subclinical microbial contamination as a cause of aseptic loosening.
–While the goal of cartilage imaging is to develop tools that are fast, inexpensive, sensitive, accurate, and noninvasive, there is growing interest in the use of more direct, invasive techniques such as optical coherence tomography (OCT),5 which could be used in vivo at the time of surgery to analyze cartilage damage.
- Li Y, Liu T, Van Halm-Lutterodt N, Chen J, Su Q, Hai Y. Reprogramming of blood cells into induced pluripotent stem cells as a new cell source for cartilage repair. Stem Cell Res Ther.2016 Feb 17;7:31.
- Meppelink AM, Zhao X, Griffin DJ, Erali R, Gill TJ, Bonassar LJ, Redmond RW,Randolph MA. Hyaline articular matrix formed by dynamic self-regenerating cartilage and hydrogels. Tissue Eng Part A.2016 Jul;22(13-14):962-70. Epub 2016 Jul 7.
- Getzlaf MA, Lewallen EA, Kremers HM, Jones DL, Bonin CA, Dudakovic A,Thaler R, Cohen RC, Lewallen DG, van Wijnen AJ. Multi-disciplinary antimicrobial strategies for improving orthopaedic implants to prevent prosthetic joint infections in hip and knee. J Orthop Res.2016 Feb;34(2):177-86. Epub 2015 Dec 29.
- Palmer MP, Melton-Kreft R, Nistico L, Hiller NL, Kim LH, Altman GT, Altman DT, Sotereanos NG, Hu FZ, De Meo PJ, Ehrlich GD. Polymerase chain reaction-electrospray-time-of-flight mass spectrometry versus culture for bacterial detection in septic arthritis and osteoarthritis. Genet Test Mol Biomarkers.2016 Dec;20(12):721-31. Epub 2016 Oct 17.
- Novakofski KD, Pownder SL, Koff MF, Williams RM, Potter HG, Fortier LA. High-resolution methods for diagnosing cartilage damage in vivo. 2016 Jan;7(1):39-51.
Dr. Warren ponders whether his decision to jettison an “academic pedigree” in favor of a private practice in western Florida was a good career choice. In answering that question with a resounding “yes,” Dr. Warren’s essay reminds readers that the definition of “success” is intensely personal. In his case, what matters most is being a solid orthopaedic diagnostician and surgeon, a loving father and husband, a philanthropist, and a respected member of his religious and secular communities.
If you would like JBJS to consider your “What’s Important” story for publication, please submit a manuscript via Editorial Manager. When asked to select an article type, please choose Orthopaedic Forum and include “What’s Important:” at the beginning of the title.
Because they are personal in nature, “What’s Important” submissions will not be subject to the usual stringent JBJS peer-review process. Instead, they will be reviewed by the Editor-in-Chief, who will correspond with the author if revisions are necessary and make the final decision regarding acceptance.
I’m constantly searching for JBJS content to do my job at The Journal. That’s why I’m thrilled with the power, speed, and accuracy of the new search engine that’s at the heart of the reimagined and reengineered jbjs.org.
Here are just a few examples of what happens when you use the “enter a search query” bar at the top of every page on the new website:
- As you type a common orthopaedic word, such as distal, you get a drop-down list of popular terms with that word included. Very often, what you’re looking for is in the list, so you can stop typing and simply click. (This works just like a popular feature in an often-used search engine that I won’t name here.)
- When you search a phrase or condition, such as distal radial fracture, you get relevant articles, images, videos, webinars, and podcasts from the flagship JBJS, as well as from JBJS Essential Surgical Techniques, JBJS Reviews, JBJS Open Access, and JBJS Case Connector. You can also easily filter your results by publication name.
- If you know the digital object identifier (DOI) of a JBJS article of interest, simply paste it into the search bar (beginning with the numeral 10), and you’ll get that specific result. The same holds true for complete or partial article titles, even if they are long.
- When you search for an author by last name, your top hits are articles in which that name appears as an article author, rather than articles in which it appears in the reference list.
- Once you’ve found what you’re looking for, click on the star icon to automatically save the item to your customized “My JBJS” folder.
In developing this improved search experience, JBJS listened to a broad array of orthopaedic website users, young and old. Over the last five-plus years, this (old) user has searched for JBJS content on four different platforms using four different search tools, and this one is by far the most satisfying.
Complimentary access to the new jbjs.org is available until March 1, 2018.
JBJS Developmental Editor
No matter how you look at it, orthopaedic residency is a relentlessly challenging five or six years. The Journal of Bone & Joint Surgery offers the following special services to make life and learning a little easier for orthopaedists in training:
- Complimentary access to all JBJS journals via the AOA’s Council of Orthopaedic Residency Directors (CORD)
- Guidance for getting the most out of your Journal Club
- Annual grants ($2,500) to support Journal Club activities
- Free access to JBJS Podcasts, Videos, and Webinars
- Opportunities to participate in the JBJS blog, OrthoBuzz
Residents who connect now with JBJS establish a solid foundation for a career of lifetime orthopaedic learning. Click on the “Residents” button under “Editorial Resources” at www.jbjs.org to find out more.
In 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.”
Nowadays, chronic deep periprosthetic joint infections (PJIs) are typically treated with 2-stage exchange arthroplasty, but what about acute PJIs? In the December 6, 2017 edition of JBJS, Bryan et al. report on a retrospective cohort study of acute infections after hip arthroplasty. The results suggest we’ve come a long way in identifying patients with early infections and that contemporary irrigation-and-debridement protocols are more successful than older methods.
The researchers studied 6-year outcomes in 90 hips that had undergone either total or hemiarthroplasty and that were determined to have either acute early postoperative infections (n=66) or acute hematogenous infections (n=24). All the infected hips were managed with either irrigation, debridement, and modular head and liner exchange (70%) or with irrigation and debridement alone (30%). The authors stratified the patients into those without comorbidities (A), those with 1 or 2 comorbidities (B), and those with >2 comorbidities (C). Postoperatively, patients were treated with broad-spectrum intravenous antibiotics, followed by targeted therapy administered by infectious disease specialists.
Of the 90 acute infections, failure—defined as uneradicated infection, subsequent removal of any component for infection, unplanned second wound debridement for ongoing infection, or infection-related mortality—occurred in 15 hips (17%). Of those 15, 9 required component removal. The chances of treatment failure were slightly higher in cases of hematogenous infection (21%), compared with acute early postoperative infection (15%), but that difference was not statistically significant. Significant comorbidity-related failure-rate differences were found: failure occurred in 8% of the grade-A patients, 16% of grade-B patients, and 44% of grade-C patients. The most common infecting organism was methicillin-sensitive Staphylococcus aureus (MSSA).
From this overall 6-year success rate of 83%, the authors conclude that “with modern inclusion criteria for acute infection, modern surgical techniques, and modern antibiotic therapy…the rate of success was higher than in most historic reports.”