Pediatric orthopaedists have long been searching for anatomic, mechanical, and metabolic causes of slipped capital femoral epiphysis (SCFE). Adolescent obesity has been a recognized SCFE risk factor for 50 years. (Interestingly, high BMI is a consistent risk factor in males, but females who experience SCFE are often thin.) Possible racial risk factors have been examined as well, with no clear conclusions.
Because the incidence of SCFE is relatively low (1 in 10,000 children according to this JBJS Clinical Summary) and the risk of bilaterality is high (in the range of 30% to 40%), it seems likely that anatomic risk factors are at play. In the January 2, 2020 issue of The Journal, Novias et al. home in on the 3-D anatomy of the epiphyseal tubercle (a small, round protuberance thought to stabilize the epiphysis) and peripheral “cupping” of the epiphysis in patients with and without SCFE.
They found a smaller epiphyseal tubercle and more extensive epiphyseal cupping in patients with SCFE compared with normal hips. The authors encourage further investigation of the first finding to determine whether smaller tubercles are a consequence of the slip process or an anatomic variant that predisposes the epiphysis to slip.
A major strength of this study is that all measurements were made by a single observer blinded to the diagnosis of SCFE and other potentially confounding clinical and demographic data. Also, the measurement processes used in this study have been previously validated.
Investigation into the anatomic features of this disease should continue, along with development of minimally invasive, safe, and inexpensive ways to screen for possible anatomic risk factors. The most pertinent clinical goals are to continue evolving minimally invasive methods of epiphyseal stabilization to prevent and/or treat SCFE and to more accurately identify hips at risk of SCFE.
Marc Swiontkowski, MD
The treatment of early-onset scoliosis with Mehta casting is a long process, but if successful, it can delay or obviate the need for surgery. In the September 4, 2019 issue of JBJS, Fedorak et al. examine outcomes among 38 patients (mean age of 24 ± 15 months at time of first casting) who were treated with Mehta casting and followed for a mean of 8 ± 2 years. The retrospective review identified differences between patients who had a Cobb angle ≤15° (improvement group) at the most recent follow-up and those who had a Cobb angle of >15° (no-improvement group).
Forty-nine percent of children had achieved and maintained scoliosis of ≤15° at the time of the most recent follow-up, and 73% were improved by at least 20°, although 3 children ended up relapsing after meeting recommended criteria for discontinuation of casting. There was no significant difference in thoracic-height gain between the groups, demonstrating that even when scoliosis was not corrected, growth was maintained during cast treatment.
Patients in the improvement group had a mean age of 18.9 ± 12 months and scoliosis of 48.2° ± 14° at the initiation of treatment. Here are 3 additional factors that were associated with a greater likelihood of scoliosis of ≤15°:
- A lower pre-treatment Cobb angle and traction Cobb angle
- A smaller rib-vertebral angle difference on first-in-cast radiograph
- A lower Cobb angle on first-in-cast radiograph
The authors note that although this study analyzed longer-term follow-up data than most other similar investigations, “treatment of early-onset scoliosis is not truly finished until skeletal maturity has been reached.”
Orthopaedists are seeing an increasing number of active, young patients with hip pain. A study by May et al. in the March 20, 2019 issue of The Journal of Bone & Joint Surgery strongly suggests that osteoid osteoma (OO)—a small, benign tumor characterized by dense sclerotic bone tissue—should not be overlooked in the differential diagnosis when working up these patients.
The authors identified and reviewed the records of 50 children and adolescents (mean age of 12.4 years) at their tertiary-care pediatric center who had received a diagnosis of OO within or around the hip between 2003 and 2015. Nighttime hip and/or thigh pain (90%) and symptom relief with NSAIDs (88%) were common clinical findings.
Sclerosis/cortical thickening was visible in 58% of the radiographs. Perilesional edema and a radiolucent nidus was found on all 43 of the available CT scans, leading the authors to conclude that “CT scans provide definitive diagnosis” of OO.
Unfortunately, 46% of these patients initially received an alternative diagnosis, the most common of which was femoroacetabular impingement (FAI), and a delay in diagnosis of >6 months occurred in 43% of patients. The authors note that concerns regarding radiation exposure have led some clinicians to order MRI rather than CT when evaluating pediatric hip disorders, but this study found that identifying an OO nidus with MRI was not as accurate as doing so with CT.
Regarding treatment, among the 41 patients who ultimately underwent percutaneous radiofrequency ablation (RFA) to treat OO, 93% achieved complete post-RFA symptom resolution. Complications from RFA occurred in 7% of patients who underwent the procedure.
Every month, JBJS publishes a review of the most pertinent and impactful studies published in the orthopaedic literature during the previous year in one of 13 subspecialties. Click here for a collection of all OrthoBuzz subspecialty summaries.
This month, Kelly L. VanderHave, MD, co-author of the February 20, 2019 “What’s New in Pediatric Orthopaedics,” selected the five most compelling findings from among the more than 50 noteworthy studies summarized in the article.
—A before-and-after comparison found that, after implementation of a dedicated, weekday operating room reserved for pediatric trauma, length of stay for 5 common pediatric orthopaedic fractures was reduced by >5 hours. In addition, cost was reduced by about $1,200 per patient; complication rates improved slightly; frequency of after-hours surgery decreased by 48%; and wait times for surgery were significantly reduced.
—Forty-two patients with a distal radial buckle fracture received a removable wrist brace during an initial clinic visit, along with instructions to wear it for 3 to 4 weeks. No follow-up was scheduled, but the family was contacted at 1 week and at 5 to 10 months following treatment. No complications or refractures occurred; 100% of respondents said they would select the same treatment.1
Pediatric Sports Medicine
—Among a continuous cohort of 85 patients (mean age 13.9 years) who underwent primary ACL reconstruction (77% with open physes at time of surgery) and who were followed for a minimum of 2 years, overall prevalence of a second ACL surgery was 32%, including 16 ACL graft ruptures and 11 contralateral ACL tears. A slower return to sport was found to be protective against a second ACL injury.
Infection and Scoliosis Surgery
—A preliminary study of 36 pediatric patients who underwent a total of 191 procedures for early-onset scoliosis found that the use of vancomycin powder during closure significantly decreased the rate of surgical site infection (13.8% per procedure in the control group versus 4.8% per procedure in the vancomycin group).
—A retrospective review of >1,100 clubfeet that were presumed to be idiopathic upon presentation found that the condition in 112 feet (8.9%) was later determined to be associated with neurological, syndromic, chromosomal, or spinal abnormalities—and therefore nonidiopathic.2 The nonidiopathic group was less likely to have a good result at the 2- and 5-year follow-up, and more likely to require surgery. The authors conclude, however, that surgery is avoidable for most patients with nonidiopathic clubfoot.
- Kuba MHM, Izuka BH. One brace: one visit: treatment of pediatric distal radius fractures with a removable wrist brace and no follow-up visit. J Pediatr Orthop.2018 Jul;38(6):e338-42.
- Richards BS, Faulks S. Clubfoot infants initially thought to be idiopathic, but later found not to be. How do they do with nonoperative treatment?J Pediatr Orthop. 2017 Apr 10. [Epub ahead of print].
Up to 40% of kids who experience a slipped capital femoral epiphysis (SCFE) in one hip develop a slip in the contralateral hip. Recent research in pediatric orthopaedics has attempted to identify risk factors for a second SCFE in patients who have had a first. A retrospective study by Maranho et al. in the February 6, 2019 issue of JBJS provides additional evidence about one particular risk factor.
The authors radiographically measured the epiphyseal tilt, epiphyseal extension ratio, alpha angle, and epiphyseal angle of the uninvolved, contralateral hip among 318 patients (mean age of 12.4 years) who presented for treatment of a unilateral SCFE between 2000 and 2017. After adjusting for triradiate cartilage status, Maranho et al. found that, over a minimum follow-up of 18 months:
- Increased posterior epiphyseal tilt was associated with an increased risk of contralateral SCFE, which corroborates recent findings. Specifically, an epiphyseal tilt of >10° corresponded to a 54% predicted probability of a contralateral slip in patients with open triradiate cartilage.
- Increased epiphyseal extension around the metaphysis in the superior plane had a protective effect against a contralateral SCFE. For each 0.01 increase in superior epiphyseal extension ratio, the odds of a contralateral slip decreased by 6%.
- The alpha angle and epiphyseal angle were not independently associated with a contralateral slip.
Clinically, the authors suggest that the tilt findings may be more useful than the extension-ratio findings, especially when it comes to the difficult decision around whether to perform prophylactic percutaneous pinning of the contralateral hip. They write that “prophylactic fixation may be discussed with the families of patients presenting with unilateral SCFE who have a tilt angle of >10°,” noting that this threshold “would result in a low proportion of patients undergoing unnecessary prophylactic pinning.” Maranho et al. are quick to add that even contralateral hips with epiphyseal tilt angles <10° are at risk of SCFE and should be closely monitored.
How much opioid analgesia do pediatric patients need after closed reduction and percutaneous pinning of a supracondylar humeral fracture? Not as much as they are being prescribed, suggests a study of 81 kids (mean age of 6 years) by Nelson et al. in the January 16, 2019 issue of The Journal of Bone & Joint Surgery.
All patients in the study underwent closed reduction and percutaneous pinning at a single pediatric trauma center. The authors collected opioid utilization data and pain scores (using the Wong-Baker FACES scale) for postoperative days 1 to 7, 10, 14, and 21 via a text-message system, with automated text queries sent to the phones of the parents/guardians of the patients. (Click here for another January 16, 2019 JBJS study that relied on text messaging.)
Not surprisingly, the mean postoperative pain ratings were highest on the morning of postoperative day 1, but even those were only 3.5 out of a possible 10. By postop day 3, the mean pain rating decreased to <2. As you’d expect, postoperative opioid use decreased in parallel to reported pain.
Overall, patients used only 24% of the opioids they were prescribed after surgery. (See related OrthoBuzz post about the discrepancy between opioids prescribed and their actual use by patients.) Considering that pain levels and opioid usage decreased in this patient population to clinically unimportant levels by postoperative day 3, the authors conclude that “opioid prescriptions containing only 7 doses would be sufficient for the majority of [pediatric] patients after closed reduction and percutaneous pinning without compromising analgesia.”
Now that some normative data such as these are available, Nelson et al. “encourage orthopaedic surgeons treating these common [pediatric] injuries to reflect on their opioid-prescribing practices.” They also call for prospective randomized studies into whether non-narcotic analgesia might be as effective as opioid analgesia for these patients.
Most patients with clinically apparent juvenile osteochondritis dissecans (JOCD) are between 12 and 19 years of age. Often the disease can be treated successfully with nonoperative modalities, but even in cases where the initial lesion resolves, patients may be predisposed to osteoarthritis later in life. While repetitive microtrauma is suspected to be involved in the development of JOCD, the exact etiology remains poorly understood, even 130 years after the condition was first described.
In the December 19, 2018 issue of The Journal, Toth et al. histologically examined 59 biopsy samples from the central condyles of 26 pediatric cadavers to look for areas of epiphyseal cartilage necrosis. Hypothesizing that such evaluation would reveal some lesions similar to those found in animals, the authors did indeed identify 6 samples with 1 or more areas of necrotic cartilage, which were either incorporated into subchondral bone or associated with focal failure of endochondral ossification. Those characteristics are consistent with a similar disease process called osteochondrosis manifesta seen in pigs and horses. While the clinical significance of these findings remains to be determined, the authors suggest that they may help explain an epiphyseal etiology of JOCD, and the data suggest that these microscopic changes (some of which are rendered in this article as whole-slide images) are probably present in young people 5 to 10 years prior to the clinical manifestations of JOCD.
These findings lend credence to the theory that the underlying etiology of JOCD primarily involves the epiphyseal growth plate rather than subchondral bone. Furthermore, the similarities between these cadaveric specimens and osteochondrosis manifesta lesions in porcine and equine femoral condyles may help us develop improved models to better diagnose, prevent, and treat this pathology.
Chad A. Krueger, MD
JBJS Deputy Editor for Social Media
The evidence favoring tranexamic acid (TXA) for reducing surgical blood loss is ample and growing, but until now robust data were sparse regarding its efficacy in the setting of adolescent idiopathic scoliosis surgery. In the December 5, 2018 issue of The Journal of Bone & Joint Surgery, Goobie et al. report on a randomized, blinded, placebo-controlled trial showing that, in that population, TXA reduced perioperative blood loss by 27%, compared with blood loss in a placebo group.
Even with recent advances in scoliosis surgical technique, blood transfusions are common. And, because transfusions are associated with significant morbidity and mortality, limiting operative blood loss and reducing the need for transfusion have become focal points for orthopaedic surgeons.
In this Level-I trial, >100 patients between the ages of 10 and 18 years undergoing elective posterior instrumented spinal fusion were randomized to receive either TXA (infusion of a 50-mg/kg loading dose and a 10-mg/kg/h maintenance dose) or normal saline (delivered in the same way and dose) during surgery. The TXA group demonstrated an overall 27% reduction in cumulative blood loss and a 2-fold reduction in the percentage of patients with clinically relevant blood loss (defined as >20 mL/kg).
The cumulative effect of reduced blood loss was enhanced over time, with the positive effect of TXA being most evident in procedures lasting >4 hours. None of the patients in the TXA group required a transfusion or developed side effects such as thromboembolism or seizures.
In an interesting sidenote, the authors asked the participating orthopaedic surgeons, who were blinded to the randomization, to guess which group each patient had been assigned to by evaluating the relative ooziness of the surgical field. The surgeons guessed correctly 72% of the time.
Overall, these findings prompted the authors to conclude that “the use of TXA as part of a multimodal blood management strategy, as was employed in this study, should be considered the standard of care for patients undergoing surgery for adolescent idiopathic scoliosis.”
Under 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:
Tibia Vara: Osteochondrosis Deformans Tibia
WP Blount: JBJS, 1937 January; 19 (1): 1
In this classic article, Blount detailed clinical and radiologic features of the affected lower extremities of 13 children with bowlegs. Nearly 80 years have passed since Blount’s original description, and not much more is known about this enigmatic developmental disorder. Given the potential for less postoperative morbidity, there has been a resurgence of “guided growth” strategies to treat this and other pediatric limb deformities.
Lumbar Disc Disorders and Low-back Pain: Socioeconomic Factors and Consequences
JN Katz: JBJS, 2006 April; 88 (Suppl 2): 21
The 21st century has brought with it a sharper focus on both the socioeconomic factors contributing to medical conditions and the socioeconomic consequences of those conditions. Back in 2006, Dr. Katz found that the total annual costs of low back pain in the US exceeded $100 billion, two-thirds of that in the form of indirect costs (e.g., lost wages and reduced productivity). He also found that fewer than 5% of patients who have a low back pain episode account for 75% of the total costs, prompting Dr. Katz to emphasize the ongoing “critical importance of identifying strategies to prevent these disorders and their consequences.”
OrthoBuzz occasionally receives posts from guest bloggers. This guest post comes from Carl Nunziato, MD and Anthony Johnson, MD in response to a TV news segment on WLWT in Cincinnati.
While viewing the WLWT segment on youth sports injury, we were encouraged that the reporter sought out a local orthopedic surgeon to comment on the risks associated with single-sport specialization. As orthopaedic surgeons, our opinions are a trusted voice in our communities, and we need to educate athletes, coaches, and parents alike of the dangers of such specialization. We commend Dr. Timothy Kremchek for his involvement in his local community and have felt the frustration he expressed regarding the rising sport-injury rates among adolescents.
However, we caution providers against characterizing single-sport specialization as “child abuse,” as Dr. Kremchek did in this segment. This extreme language, even if used to emphasize the potentially serious nature of some sport injuries, is counterproductive. Instead, we encourage all musculoskeletal clinicians to focus on educating the public on how to reduce risk in adolescent athletes, rather than shaming or blaming.
We’ve helped many patients—both minors and adults—as they struggled to rehab from injuries, only to realize that returning to the same level of competition may not be possible. In such cases, many patients and/or their parents ask the same guilt-ridden questions as the mother of the young basketball player in the news segment: “Did I make a mistake? Did I push too hard?”
It is true that youthful participation in a single sport year-round has been shown to result in increased injury rates, burnout, and possibly even limitations in peak performance in the chosen sport due to delayed development of other muscle groups and fine motor skills. We also cannot deny the risks and costs associated with the increase in operations on young athletes. It’s key to remember, however, the principal concept of patient autonomy. As the young patient in the story reminds us, these kids often truly love their sport – and many would choose to continue participating even if they knew the risk and seriousness of eventual injury.
Instead of using sensational phrases like “child abuse,” which may frighten families or stir up feelings of guilt, we should provide resources for coaches, parents, physicians, and athletes aimed at encouraging healthy participation and minimization of one-sport injuries. One example is the AAOS/AOSSM OneSport initiative. Educating patients and their families requires significant time and effort on the part of the orthopaedic surgeon, but it is likely to result in a more positive interaction with the patient and parents. And these interactions may help emphasize the long-term lifestyle behaviors that we are hoping to cultivate among these vulnerable populations.
Carl A. Nunziato, MD is a resident in orthopaedic surgery at Dell Medical School in Austin, Texas. Anthony Johnson, MD is the orthopaedic surgery residency program director in the Department of Surgery and Perioperative Care at Dell Medical School.