Tag Archive | JBJS Open Access

“Normal” Ultrasound May Not Rule Out DDH Later in Childhood

Some years ago, we moved away from calling hip dysplasia “congenital” and started using the term “developmental dysplasia of the hip” (DDH). Indeed, it is developmental. As a surgeon specializing in pediatric orthopaedics and hip preservation, I see not only infants when DDH is of potential concern but also young adults with more mature manifestations of hip dysplasia not previously diagnosed or treated.

Screening protocols have successfully helped in the early identification of DDH and dislocation, but what is the likelihood that infants with risk factors for dysplasia but normal ultrasound results will go on to experience DDH in childhood? And which risk factors are predictive?

In a recent report in JBJS Open Access, Humphry et al. provide new insight into these challenging questions. This study from the UK included 1,053 children from a cohort of 2,191 children who had been assessed as newborns and had at least 1 of 9 perinatal risk factors for DDH. All had undergone ultrasound at a mean of 8 weeks and were followed clinically.

The mean age of the children in the current study was 4.4 years (range, 2.0 to 6.6 years). Thirty-seven of the participants had been treated for DDH in the postnatal period, predominantly with a harness.

Assessing the acetabular index (AI) on pelvic radiographs, the authors found that:

  • 27 of the children had “severe” hip dysplasia (an AI of >2 standard deviations above age and sex reference values). Girls were more likely to have this outcome. Only 3 of the 27 received treatment for DDH in infancy.
  • 146 (13.9%) of the children had an AI of >20°, only 12 of whom had been treated during infancy; 92% had no prior diagnosis of DDH. On multivariate analysis, female sex and breech presentation at birth were significantly predictive of this “mild” dysplasia (breech presentation demonstrated a nearly twofold increased odds of an AI of >20° at ≥3 years of age), while first-born status had a protective effect.

The findings of this study lend support to radiographic monitoring later in childhood for patients with risk factors such as breech positioning at birth. While the exact algorithm of ultrasound and radiographic workup still needs to be elucidated, it appears that a “normal” ultrasound in infancy does not necessarily rule out the development of hip dysplasia in children with select risk factors.

Matthew R. Schmitz, MD
JBJS Deputy Editor for Social Media

“Inflation” and Bias in Letters of Recommendation

OrthoBuzz occasionally receives posts from guest bloggers. This guest post comes Christopher Dy, MD, MPH in response to 2 recent studies in JBJS Open Access.

It’s that time of year when many of us write and review letters of recommendation (LOR) for orthopaedic residency applicants. LOR have always played a large part in the ranking and selection of applicants, and they may be weighed even more heavily during the upcoming “virtual-interview” season. Many applicants present remarkable objective measures of accomplishment, accompanied by 3 to 4 glowing LOR from colleagues. But can all these people really be that good? I am not the first to wonder whether “grade inflation” has crept into the writing of recommendation letters.

As letter writers, we fulfill two important, but potentially conflicting, roles:

  1. Mentors: We want to support the applicants who have worked with us.
  2. Colleagues: We want to be honest with our peers who are reviewing the applications.

In addition, this dynamic is now playing out in the context of our profession’s efforts to increase the racial and gender diversity of the orthopedic workforce. This begs the question as to whether there are differences in how we describe applicants based on race and gender.

To help answer that question, our research team analyzed LOR from 730 residency applications made during the 2018 match. Using text-analysis software, we examined race- and gender-based differences in the frequency of words from 5 categories:

  1. Agency (e.g., “assertive,” “confident,” “outspoken”)
  2. Communal (e.g., “careful,” “warm,” “considerate”)
  3. Grindstone (e.g., “dedicated,” “hardworking,” “persistent”)
  4. Ability (e.g., “adept,” “intelligent,” “proficient”)
  5. Standout (e.g., “amazing,” “exceptional,” “outstanding”)

We hypothesized that men and women would be described differently, expecting, for example, that agency terms would be used more often for describing men and communal terms more often for describing women.

Our hypothesis was almost entirely wrong. The agency, communal, grindstone, and ability words were used similarly for both male and female applicants. Standout words were used slightly (but significantly) more often in letters describing women. When comparing word usage in LOR for white candidates to those of applicants underrepresented in orthopedics, standout words were more commonly used in the former, and grindstone words were more commonly used in the latter. Interestingly, neither gender nor race word-usage differences were observed when LOR using the American Orthopaedic Association (AOA) standardized letter format were analyzed.

In a separate but related study, we looked at the scores given in each of the 9 domains of the AOA standardized letter of recommendation. These scores clustered far “to the right,” with 75% of applicants receiving a score of ≥85 in all domains. While I am certain that orthopaedic residency applicants are universally very talented all-around, this lopsided scoring distribution makes it very hard to differentiate among candidates. Furthermore, 48% of applicants were indicated as “ranked to guarantee match.” I suspect that the “ranked to guarantee match” recommendation is made more often than it should be. Again, this “inflation” makes it challenging for applicants to stand out – and may have especially important implications in this year’s virtual-interview environment.

What I take away from these two studies is that our natural tendency as orthopedic surgeons is to write effusively about our student mentees. Perhaps the differences in how we describe applicants based on their race and gender can be mitigated by using the AOA standardized letter format, but that format has a profound ceiling effect that makes it hard to discern the “cream of the crop.”

As a specialty, we are truly fortunate to have such excellent students vying to be orthopedic surgeons, and it is quite possible that nearly all of the applicants applying for our residency programs would make great orthopedic surgeons. However, it would help us to have a baseline measure of how we rate our students. Having some kind of benchmark against which to measure our past rankings and how they compare to those of our peers would help immensely.

Christopher Dy, MD, MPH is a hand and wrist surgeon, an assistant professor of orthopaedic surgery at Washington University School of Medicine in St. Louis, and a member of the JBJS Social Media Advisory Board.

JBJS Essential Surgical Techniques and JBJS Open Access Now in PubMed Central

PMC LogoThe Editors of The Journal of Bone & Joint Surgery (JBJS) are pleased to announce that JBJS Essential Surgical Techniques (EST) and JBJS Open Access (OA) are now archived in PubMed Central (PMC), the national repository of free full-text biomedical literature, and discoverable on PubMed.

Launched in 2011 and edited by Edward Cheng, MD, JBJS Essential Surgical Techniques offers readers an expanding online library of thoroughly vetted orthopaedic procedures, including high-quality instructional videos. Peer reviewed and derived from top-quality published clinical studies, EST articles and videos deliver detailed, practical surgical guidance to all orthopaedists—from seasoned practitioners to those just starting out in practice.

Launched in 2016, JBJS Open Access gives authors an open-access option bolstered by the outstanding service and editorial excellence that JBJS has delivered for more than 125 years. At the same time, orthopaedic clinicians and researchers worldwide benefit from all-inclusive access to the best clinical and basic-science content about musculoskeletal health and injury care. JBJS OA is co-edited by Eng Lee, MD, FRCSC and Robin Richards, MD, FRCSC.

To learn more about JBJS Essential Surgical Techniques, click here.

To learn more about JBJS Open Access, click here.