OrthoBuzz occasionally receives posts from guest bloggers. This guest post comes from Impact Science, in response to a recent article in JBJS.
Pain management is an important aspect of postoperative care after posterior spinal fusion for the treatment of adolescent idiopathic scoliosis (AIS). Opioid medications, while highly effective and commonly used for postoperative analgesia, have many well-documented adverse effects. Several recent studies have suggested that dexamethasone, a glucocorticoid, is an effective adjunct for postoperative pain management after many adult orthopaedic procedures, but its use after AIS surgery has not been well studied.
Beginning in 2017, doctors at Children’s Healthcare of Atlanta added dexamethasone to their postoperative pain control pathway for adolescent spinal-fusion patients. In the October 21, 2020 issue of The Journal of Bone & Joint Surgery, Fletcher et al. report findings from a cohort study that investigated the postoperative outcomes of 113 patients (median age of 14 years) who underwent posterior spinal fusion between 2015 and 2018. The main outcome of interest—opioid consumption while hospitalized—was determined by converting all postoperative opioids given into morphine milligram equivalents (MME).
Because dexamethasone entered their institution’s standardized pathway for this operation in 2017, it was easy for the authors to divide these patients into two groups; 65 of the study patients did not receive postoperative steroids, while 48 patients were managed with 3 doses of steroids postoperatively. Relative to the former group, the latter group showed a 39.6% decrease in total MME used and a 29.5% decrease in weight-based MME. Patients who received postoperative dexamethasone were also more likely to walk at the time of initial physical therapy evaluation. Notably, the authors found no differences between the groups with regard to wound dihescence or 90-day infection rates—2 complications that have been associated with chronic use of perioperative steroids.
In commenting on these findings, Amy L. McIntosh, MD from Texas Scottish Rite Hospital for Children writes that she was so impressed that she plans “on adding dexamethasone to our institution’s standardized AIS care pathway.”
Impact Science is a team of highly specialized subject-area experts (Life Sciences, Physical Sciences, Medicine & Humanities), who collaborate with authors, societies, libraries, universities, and various other stakeholders for services to enhance research impact. Through research engagement and science communication, Impact Science aims at democratizing science by making research-backed content accessible to the world.
Identifying the pathogenic microorganism in childhood osteomyelitis and septic arthritis is essential to tailoring appropriate treatment. But the traditional methods of swab and tissue culturing have subpar success rates in pediatric patients, identifying the pathogen in only 40% to 60% of cases. In the October 21, 2020 edition of The Journal, Shin et al. report their findings comparing microbial identification rates using pediatric blood culture bottles (BCBs), typical culture swabs, and tissue specimens.
Over 3 years, the authors prospectively collected intraoperative specimens from 40 pediatric patients (mean age of 7.2 years) who underwent surgery for a presumed osteoarticular infection. Half of the patients had received oral or intravenous antibiotics in the 3 weeks prior to surgery, while the other half had received intravenous cefazolin after culture specimens were obtained in the operating room. Intraoperative culture specimens were obtained in 3 different manners for all patients:
- Four 21-gauge needles were dipped into the infected fluid and were used to inoculate 4 pediatric BCBs – 2 aerobic and 2 nonaerobic.
- Two swabs were placed in direct contact with the infected tissue.
- Two solid tissue samples were collected and placed in 2 sterile containers.
In these 40 cases, the microbial identification rate of the BCB method was 68%, compared to 45% with the swab method and 38% with the tissue method—all statistically significant differences. In 9 patients (23%), the pathogen was only identified with the BCB method. No samples showed positive culture growth with the other 2 methods if the BCB culture was negative. Interestingly, in a subgroup analysis of 15 patients with methicillin-susceptible Staphylococcus aureus (MSSA), the authors found no difference in detection rates between the 3 methods, but in cases involving organisms other than MSSA, detection with BCBs was significantly higher than with both swab and tissue cultures.
The apparent superiority of BCBs to detect microbial organisms could be due to the characteristics of pediatric BCBs, which enhance microorganism growth in a small amount of liquid. Although there are some concerns that this enhanced BCB detection could lead to increased rates of false-positives from contaminants, I think the risk of false positives is a viable tradeoff if we can more quickly and accurately identify pathogens in pediatric infections. As Shin et al. emphasize, “Sequelae resulting from these infections are particularly unfortunate for pediatric patients.”
Matthew R. Schmitz, MD
JBJS Deputy Editor for Social Media
There has been a huge worldwide effort over the last 2-plus decades to establish arthroplasty registries. Among the many advantages of such registries, advocates emphasize the potential detection of early failures associated with new implant designs and biomaterials. The large number of patients enrolled in most registries and the methodical capturing of data yield substantial statistical and research benefits.
Based on the successes of arthroplasty registries, parallel registries have been established for sports medicine (especially for shoulder and knee conditions and treatments), fractures, musculoskeletal tumors, and others. Although the focus has been on enrolling large numbers of patients with relatively common disorders or procedures, there have been less well-publicized efforts to create smaller registries of rarer diseases.
In the October 21, 2020 issue of The Journal, Forman et al. use the 8-site Congenital Upper Limb Differences (CoULD) registry to report on associations between congenital deficiency of the radial aspect of the forearm in 259 patients (383 involved limbs) and thumb hypoplasia. Two findings stood out to me:
- The severity of radial deficiency was correlated with the severity of thumb deficiency.
- Compared with subjects who had no diagnosed syndromes, patients with concomitant syndromes (such as VACTERL and Holt-Oram) were twice as likely to have bilateral deficiency and 2.5 times as likely to have radial and thumb deficiencies as opposed to thumb deficiency alone.
In addition to reinforcing findings from previous single-institution studies, these data from Forman et al. will help surgeons counsel parents, determine treatment approaches, and establish frameworks for following patient outcomes after both surgical and nonsurgical treatment. It is my hope that other clinician-researchers with interest in understanding and managing rare conditions will establish similar registries to benefit these smaller but no-less-important groups of patients and families.
Click here to read the JBJS Clinical Summary on Congenital Hand Differences.
Marc Swiontkowski, MD
In the October 7, 2020 issue of The Journal, Du et al. report on a multicenter database-derived cohort of 167 patients with early-onset scoliosis treated with traditional growing rods and followed for ≥2 years after “final” fusion. These researchers report that 19% of those patients required a repeat surgery following fusion, most commonly for surgical-site infection and anchor-site failure. Multivariate analysis of risk factors for reoperation following final fusion revealed the following:
- Curve progression requiring revision surgery during the spine-lengthening process
- The number of levels spanned with the growing rods
- The duration of treatment
Du et al. report these results without spin in a way that is most useful for surgeons who are considering using these implants in their armamentarium. This is the way all new technology, especially complex advances in surgical care, should be reported.
Orthopaedic implants and instruments continue to evolve, almost always toward more sophisticated digital technology, complex engineering, and more numerous moving parts. The advent of magnetic growing rods for treating early-onset scoliosis is just one example. Often such advances are reported on by surgeons who are conflicted by personal and financial interests in the technology. This leads to all manner of potential bias–indication bias, reporting bias, selection bias, and detection bias to name just a few. Readers should evaluate this type of data with a high degree of suspicion.
What we need throughout orthopaedics are more multicenter, multisurgeon, “deconflicted” cohort studies and clinical trials. When such rigorous studies are conducted to investigate “high-tech” growing rods in patients with early-onset scoliosis, I will not be surprised if researchers find the same risk factors for reoperation after fusion that Du et al. found.
Marc Swiontkowski, MD
Pes planovalgus (flatfoot) is a common condition seen in the pediatric orthopaedic clinic. We who help manage this condition differentiate it from adult acquired flatfoot deformity, primarily in that most child and adolescent patients remain asymptomatic or minimally symptomatic and rarely require surgical intervention. However, it would be nice to have data to share with young patients and their parents regarding factors associated with flatfoot symptoms.
Min et al. provide some of that data in the September 2, 2020 issue of The Journal. The authors retrospectively evaluated factors affecting the symptoms of idiopathic pes planovalgus among 123 patients (mean age of 10.1 ± 3.2 years) using the 4-domain Oxford Ankle Foot Questionnaire (OxAFQ) administered to patients and their parents. They compared questionnaire scores to 3 radiographic measurements─anteroposterior (AP) talo-first metatarsal angle, lateral talo-first metatarsal angle, and hallux valgus angles. They also analyzed the scores in relation to patient age and sex.
Min et al. found that the physical domain score for the child-reported OxAFQ decreased by 0.74 with each 1° increase in the AP talo-first metatarsal angle. Because that angle is a surrogate for forefoot abduction, this finding portends worse patient-reported outcomes in kids with greater severity of that component of flatfoot. Female sex was also associated with lower physical domain scores, with the authors postulating that this might be attributable to culturally influenced sex differences.
In addition, age was a significant factor in 3 domains of the OxAFQ. Compared with scores from younger kids, children ≥10 years old and their parents reported statistically worse outcomes with regard to school/play, emotional well-being, and footwear. In other words, at or beyond the age of 10, flatfoot deformity seems to significantly affect the patient’s choice of footwear, interferes with the ability to participate in sports and play, and may cause personal distress, such as that which comes from being teased about foot appearance.
Orthopaedists can help manage most cases of pediatric flatfoot with sound footwear recommendations and reassurance. But it appears that in the setting of increased forefoot abduction, female sex, and symptoms that persist past the age of 10 years, further investigation may be warranted. Although this study has weaknesses, it shows that there may be detriments─both physical and emotional─associated with pes planovalgus in pediatric patients that should not be ignored.
Matthew R. Schmitz, MD
JBJS Deputy Editor for Social Media
Most orthopaedic spine surgeons and neurosurgeons have come to understand that syringomyelia plays a role in some cases of scoliosis, and that the spinal-cord condition may increase the risk of cord injury during deformity-correction surgery. In the August 19, 2020 issue of JBJS, Tan et al. investigate whether radiographic and clinical outcomes after 1-stage posterior spinal fusion to correct scoliosis secondary to syringomyelia differ between patients with syringomyelia related to Chiairi-I malformation (CIM) and those with idiopathic syringomyelia.
The short answer is “no.” Although researchers found larger preoperative syringeal parameters in the CIM group, up through 2 years after scoliosis-correction surgery, they detected no significant between-group differences in coronal/sagittal parameters or in scores from the 5 domains of the Scoliosis Research Society-22 questionnaire. Moreover, the preoperative neurological status and intraoperative neuromonitoring signals were similar in both groups.
In commenting on these findings, Kent A. Reinker, MD, points out that patients who had received preoperative neurological treatment for the syrinx were excluded from the study, so “the results … do not necessarily apply to patients who have had neurological intervention prior to scoliosis surgery.” He strongly recommends that all patients with a syrinx be referred to a neurosurgeon for evaluation prior to any scoliosis surgery, concluding that “a working partnership between orthopaedic surgeons and their neurological colleagues is important when assessing these patients.”
There is a wry saying in academic medicine that “nothing ruins good results like long-term follow-up.” But long-term follow-up helps us truly understand how our orthopaedic interventions affect patients. This is especially important with procedures on children, and the orthopaedic surgeons at the University of Iowa have been masterful with long-term outcome analysis in pediatric orthopaedics. They demonstrate that again in the August 5, 2020 issue of The Journal, as Scott et al. present their results comparing outcomes among 2 cohorts of patients who underwent treatment for developmental hip dislocations between the ages of 18 months and 5 years—and who were followed for a minimum of 40 years.
Seventy-eight hips in 58 patients underwent open reduction with Salter innominate osteotomy, and 58 hips in 45 patients were treated with closed reduction. At 48 years after reduction, 29 (50%) of the hips in the closed reduction cohort had undergone total hip arthroplasty (THA), compared to 24 (31%) of hips in the open reduction + osteotomy group. This rate of progression to THA nearly doubled compared to previously reported results at 40 years of follow-up, when 29% of hips in the closed reduction group and 14% of hips in the open reduction group had been replaced.
In addition, the authors found that patient age at the time of reduction and presence of unilateral or bilateral disease affected outcomes. Patients with bilateral disease who were treated at 18 months of age had a much lower rate of progression to THA when treated with closed reduction, compared to those treated with open reduction—but the opposite was true among patients with bilateral disease treated at 36 months of age. Treatment type and age did not seem to substantially affect hip survival among those with unilateral disease.
I commend the authors for their dedication to analyzing truly long-term follow-up data to help us understand treatment outcomes among late-diagnosed developmental hip dislocations in kids. Long-term follow-up may “ruin” good results, but it gives us more accurate and useful results. And, in this case, the findings reminded us how important it is to diagnose and treat developmental hip dislocations as early in a child’s life as possible.
Matthew R. Schmitz, MD
JBJS Deputy Editor for Social Media
Lengthening the ulna is a common method of treating radial head dislocations due to hereditary multiple exostoses (HME) in pediatric patients, but the optimal amount of ulnar lengthening remains unclear. In the June 17, 2020 issue of JBJS, Huang et al. demonstrate that using the proportional ulnar length of 1.1 as a guide to ulnar lengthening can promote spontaneous correction of the radial shaft deformity. The authors arrived at the 1.1 proportion by measuring the normal lengths of the ulna and radius in 20 pediatric patients of different age groups.
Huang et al. then treated 30 forearms (average patient age of 7.4 years) that had a radial head dislocation associated with HME. They excised the osteochondroma around the physis of the distal part of the ulna prior to lengthening. They then pulled the radial head down to the plane of the ulnar coronoid process with a Kirschner wire and lengthened the ulna to predicted proportional length using a modified Ilizarov frame. The technique also facilitated lengthening of the soft tissues of the elbow.
At the time of frame removal, reduction of the dislocated radial head was achieved in 28 forearms (93%). Forearm function also improved markedly, as did radial bowing and the radioarticular angle. The actual ulnar lengthening distance in these patients was greater than the predicted lengthening using the proportional method, but that contributed to the spontaneous remodeling of the radial shaft deformity, and there were no instances of wrist impingement.
The authors conclude that this study demonstrates that, in this clinical scenario, the “proportional ulnar length is a safe and effective parameter to use as the ulnar lengthening reference value.” But they also note that the small number of patients and the average follow-up of 63 months in this study should be expanded in future research.
The tried-and-true treatment for progressive adolescent idiopathic scoliosis (AIS) is a posterior spinal fusion (PSF). However, for skeletally immature patients, there is increasing interest in motion-sparing growth modulation, specifically anterior vertebral body tethering (AVBT). Early reports on tethering looked promising, but the long-term prognosis remains fuzzy.
Newton et al. clarify this somewhat in the May 6, 2020 issue of JBJS. They retrospectively compared outcomes among a cohort of 23 AVBT patients followed for a mean of 3.4 years with those among a matched cohort of 26 PSF patients followed for a mean of 3.6 years. The groups were well-matched in terms of demographics and preoperative curve measurements, but the AVBT group was slightly less skeletally mature based on triradiate cartilage status and Sanders classification.
The authors found that both groups experienced significant postoperative curve correction, but the PSF group had significantly greater immediate correction of the main thoracic curve (78%) than the AVBT group (36%). Smaller immediate correction is to be expected in a growth-modulation procedure, which allows the spine to “grow straighter” over time with the tether. But at the final follow-up, the AVBT group had only a 43% curve correction versus 69% final follow-up correction in the PSF group. In addition, 9 revision procedures occurred in the AVBT group, versus none in the PSF group. Twelve patients (52%) in the AVBT group had evidence of broken tethers, with 3 of those patients undergoing revision surgery due to curve progression linked to tether breakage.
Overall, 12 of 23 patients in the AVBT group (52%) were deemed a “clinical success” at the end of the study (defined as a thoracic curve <35° without a need for a secondary fusion) while all 26 patients in the PSF group were deemed a clinical success. Anterior vertebral body tethering may have a role in the treatment of scoliosis in the growing spine, but the results to date, including these from Newton et al., lead me to question whether the tethering “juice” in its current form is worth the “squeeze.”
Matthew R. Schmitz, MD
JBJS Deputy Editor for Social Media
Transitional fractures of the ankle in adolescents are related to torsional injuries that occur around the time that the distal tibial physis begins to close. In recent years, treatment has moved toward screw fixation when the intra-articular fracture gap in Salter type III (Tillaux) and type IV (triplane) fractures is between 1 mm and 2 mm. The rationale for operative treatment has been that intra-articular fracture gaps should be completely reduced, particularly in younger patients, to limit the long-term risk of post-traumatic osteoarthroses. However, evidence supporting the wisdom of surgical intervention has been thin at best. (See Clinical Summary on Triplane Ankle Fractures.)
In the April 15, 2020 issue of The Journal, Lurie et al. report on a retrospective analysis of 34 patients with a triplane fracture and 23 patients with a Tillaux fracture, all of which had 2 mm to 5 mm of articular displacement. Among those 57 patients, 34 were treated with surgery and 23 with closed reduction and casting.
Based on regression analysis, nonoperative treatment, a larger intra-articular gap after closed reduction, and the presence of a grade-III complication were associated with worse functional outcomes at a mean follow-up of 4.5 years. Patients who were treated nonoperatively and had a gap ≤2.5 mm had significantly better functional scores than similar patients with a gap >2.5 mm. From this data, the authors conclude that “surgical management of these injuries likely conveys the greatest functional benefit when the intra-articular gap exceeds 2.5 mm.”
This study has the usual issues of treatment and detection bias inherent in retrospective reviews, and the measurement of fracture gaps, even with the CT scans these authors used, is not always reliable at this level of precision. Nevertheless, this data from Lurie et al. is the best we have to date to indicate that the so-called “2-mm rule” of nonoperative management of transitional ankle-fracture gaps ≤2 mm probably makes sense in most clinical situations.
Marc Swiontkowski, MD