Pediatric Monteggia Fracture-dislocations and Their Variants: An Analysis of Outcomes and Complications Over a 10-year Period.

OBJECTIVE: Monteggia fracture-dislocation variants have been well documented in adults, but most of the literature in the pediatric population is in the form of case reports. These injuries present differently in children due to the presence of immature radiocapitellar epiphyses and the flexibility of the joint that is more prone to subluxation, contributing to occult presentations and/or misdiagnoses. The purpose of this study is to investigate the outcomes and complications of true Monteggia fracture-dislocations compared with their variants in the pediatric population. METHODS: A retrospective review was performed of all patients 17 years of age and younger who sustained a true Monteggia fracture-dislocation or a Monteggia fracture-dislocation variant over a 10-year period. Patient demographics, mechanisms of injury, fracture pattern, Bado and Letts classification, treatment (operative or conservative), and complications were recorded. RESULTS: Of the 89 patients identified, 17 (19.1%) had true Monteggia fracture dislocations, and 72 (80.9%) had a Monteggia fracture-dislocation variant. The most common Monteggia fracture-dislocation variant was an olecranon fracture and concomitant radial neck fracture (65.3%, n = 47). Of the Monteggia fracture-dislocation variants, 83.3% (n = 60) were treated nonoperatively with closed reduction and immobilization or immobilization alone, whereas only 23.5% (n = 4) of the true Monteggia fracture-dislocation injuries were treated nonoperatively with closed reduction and immobilization. Overall, 14 (15.7%) patients had complications during the course of treatment, including 12 (16.7%) Monteggia fracture-dislocation variants and 2 (11.8%) true Monteggia fracture-dislocations. The most common complications were loss of range of motion (n = 6, 42.9%, all of which were nondisplaced variants), loss of reduction (n = 4, 28.6%, including 2 nondisplaced variants, 1 displaced variant, and 1 true Monteggia fracture dislocation), and malunion or nonunion (n = 2, 14.3%, both nondisplaced variants). CONCLUSION: Pediatric Monteggia fracture-dislocation variants are much more common than true pediatric Monteggia fracture-dislocations. Monteggia fracture-dislocation variants have similar complication rates to true Monteggia fracture-dislocations overall, however, nondisplaced variants exhibited a higher complication rate when treated operatively. Further studies are warranted to assess specific fracture patterns and their associated treatments that result in varying complication rates. LEVEL OF EVIDENCE: Level III-retrospective comparison study.

Understanding the Action of RARγ Agonists on Human Osteochondroma Explants.

Osteochondromas are cartilage-capped growths located proximate to the physis that can cause skeletal deformities, pain, limited motion, and neurovascular impingement. Previous studies have demonstrated retinoic acid receptor gamma (RARγ) agonists to inhibit ectopic endochondral ossification, therefore we hypothesize that RARγ agonists can target on established osteochondromas. The purpose of this study was to examine the action of RARγ agonist in human osteochondromas. Osteochondroma specimens were obtained during surgery, subjected to explant culture and were treated with RARγ agonists or vehicles. Gene expression analysis confirmed the up-regulation of RARγ target genes in the explants treated with NRX 204647 and Palovarotene and revealed strong inhibition of cartilage matrix and increased extracellular matrix proteases gene expression. In addition, immunohistochemical staining for the neoepitope of protease-cleaved aggrecan indicated that RARγ agonist treatment stimulated cartilage matrix degradation. Interestingly, cell survival studies demonstrated that RARγ agonist treatment stimulated cell death. Moreover, RNA sequencing analysis indicates changes in multiple molecular pathways due to RARγ agonists treatment, showing similarly to human growth plate chondrocytes. Together, these findings suggest that RARγ agonist may exert anti-tumor function on osteochondromas by inhibiting matrix synthesis, promoting cartilage matrix degradation and stimulating cell death.

Canal Fill of the Forearm Bones When Placing Intramedullary Nails in the Pediatric and Adolescent Populations.

BACKGROUND: In the lower extremity, studies have suggested an optimal nail diameter to medullary canal diameter (ND/MCD) ratio to minimize postoperative complications. The goal of this study was to determine whether a correlation exists between the occurrence of complications, angulation, and range of motion and the ratio of the ND/MCD in the upper extremity. METHODS: A total of 85 radius and ulna fractures treated with flexible intramedullary nails had ND/MCD ratios measured. Random-effects models were developed to determine the association between complications and ND/MCD ratio, angulation and ND/MCD ratio, and range of motion and ND/MCD ratio. The results were reported for unadjusted models and adjusted models. RESULTS: Of the 85 forearm fractures treated with intramedullary nailing, there were 3 complications. The average follow-up was 6 months. The ND/MCD ratios were categorized as <0.50, 0.50 to 0.59, and ≥0.60. There was not a significant association between the different ratios and angulation, or risk of complication. There was an association between the ND/MCD ratio ≥0.60 and decreased pronation of -1.58° (-2.77° to -0.38°) and supination of -2.68° (-4.91° to -0.46°) (P < .05). CONCLUSION: This study found that there was not an association between the nail to canal diameter ratio and postoperative angulation in forearm fractures treated with flexible intramedullary nails. When choosing a flexible nail for forearm fractures, there does not appear to be an optimal ratio; it is therefore reasonable to use the ND that passes more easily.

Discharge Opioid Prescribing Patterns in an Academic Orthopaedic Setting: Level of Training and Subspecialty Patterns.

INTRODUCTION: Despite increased research on opioids in the orthopaedic literature, little is known of the prescribing practices of orthopaedic providers based on their level of training. The purpose of this study was to describe the discharge opioid prescribing patterns of orthopaedic providers, stratifying by level of training and orthopaedic subspecialty, within a single medical system. METHODS: A retrospective review of orthopaedic surgical encounters was performed over a 1-year period for adults who received a discharge opioid prescription. Patient demographics and prescriber characteristics were collected, including the provider's level of training (attending, fellow, resident, physician assistant [PA], and nurse practitioner [NP]) and surgical subspecialty. Junior residents were postgraduate year 1 to 3, whereas senior residents/fellows were postgraduate year 4 to 6. Discharge opioids were converted to milligram morphine equivalents (MMEs). Overprescribing was defined as a prescribing more than a seven-day supply or >45 MMEs per day. Multivariable linear regression analysis determined the factors associated with discharge MMEs, whereas logistic regression determined the factors associated with overprescribing opioids. RESULTS: Of the 3,786 patients reviewed, 1,500 met the criteria for inclusion in the study. The greatest proportion of opioid prescriptions was written by junior residents (33.9%), followed by NPs (30.1%), PAs (24.1%), senior residents/fellows (10.6%), and attendings (1.2%). Compared with junior residents, senior residents prescribed -59.4 MMEs, NPs prescribed +104 MMEs, and attendings prescribed +168 MMEs (P < 0.05), whereas PAs prescribed similar amounts (P > 0.05). Orthopaedic subspecialty was also predictive of discharge MMEs (P < 0.05). Senior residents and attendings were more likely to prescribe more than seven days of opioids (P < 0.05), whereas NPs and PAs were more likely to prescribe >45 MMEs per day (P < 0.05). DISCUSSION: This study demonstrates significant variability in opioid prescribing practices according to provider level of training and subspecialty. National guidelines for opioid prescribing practices and educational programs may help reduce such variability. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Upper Extremity Compressive Neuropathies in the Pediatric and Adolescent Populations.

PURPOSE OF REVIEW: Although somewhat rare, upper extremity compressive neuropathies can occur in the pediatric and adolescent populations due to various etiologies. Some of the most common conditions seen include thoracic outlet syndrome, supracondylar process syndrome, cubital tunnel syndrome with subluxation of the ulnar nerve, and carpal tunnel syndrome. This review will focus on these diagnoses and how to address them in the pediatric and adolescent populations. RECENT FINDINGS: Due to the rarity of upper extremity compressive neuropathies in the pediatric and adolescent populations, substantial advancement in the literature does not routinely occur. However, recent literature has found a difference in the rate of various subtypes of thoracic outlet syndrome in children versus adults. Additionally, cubital tunnel syndrome associated with ulnar nerve subluxation/instability has recently been found to have better outcomes following surgical decompression of the ulnar nerve and transposition than those with stable ulnar nerves. In summary, this review provides the most recent knowledge surrounding upper extremity compressive and entrapment neuropathies in the pediatric and adolescent populations.

Incremental Effect of Academic Predictors on Nursing Admission Assessment.

This study examined the incremental values of academic predictors that may be adopted as nursing school admission criteria. The findings revealed that using additional content areas of mathematics, reading, and English in conjunction with science contributes significantly to the prediction of early nursing school success. This study demonstrates an incremental validity approach that provides valuable guidelines to inform the selection of effective, accurate, and cost-effective admission tools for screening qualified nursing candidates.

Nonlinear random-effects mixture models for repeated measures.

A mixture model for repeated measures based on nonlinear functions with random effects is reviewed. The model can include individual schedules of measurement, data missing at random, nonlinear functions of the random effects, of covariates and of residuals. Individual group membership probabilities and individual random effects are obtained as empirical Bayes predictions. Although this is a complicated model that combines a mixture of populations, nonlinear regression, and hierarchical models, it is straightforward to estimate by maximum likelihood using SAS PROC NLMIXED. Many different models can be studied with this procedure. The model is more general than those that can be estimated with most special purpose computer programs currently available because the response function is essentially any form of nonlinear regression. Examples and sample code are included to illustrate the method.