Evaluating Chat Generative Pre-trained Transformer Responses to Common Pediatric In-toeing Questions

OBJECTIVE

Chat generative pre-trained transformer (ChatGPT) has garnered attention in health care for its potential to reshape patient interactions. As patients increasingly rely on artificial intelligence platforms, concerns about information accuracy arise. In-toeing, a common lower extremity variation, often leads to pediatric orthopaedic referrals despite observation being the primary treatment. Our study aims to assess ChatGPT's responses to pediatric in-toeing questions, contributing to discussions on health care innovation and technology in patient education.

METHODS

We compiled a list of 34 common in-toeing questions from the "Frequently Asked Questions" sections of 9 health care-affiliated websites, identifying 25 as the most encountered. On January 17, 2024, we queried ChatGPT 3.5 in separate sessions and recorded the responses. These 25 questions were posed again on January 21, 2024, to assess its reproducibility. Two pediatric orthopaedic surgeons evaluated responses using a scale of "excellent (no clarification)" to "unsatisfactory (substantial clarification)." Average ratings were used when evaluators' grades were within one level of each other. In discordant cases, the senior author provided a decisive rating.

RESULTS

We found 46% of ChatGPT responses were "excellent" and 44% "satisfactory (minimal clarification)." In addition, 8% of cases were "satisfactory (moderate clarification)" and 2% were "unsatisfactory." Questions had appropriate readability, with an average Flesch-Kincaid Grade Level of 4.9 (±2.1). However, ChatGPT's responses were at a collegiate level, averaging 12.7 (±1.4). No significant differences in ratings were observed between question topics. Furthermore, ChatGPT exhibited moderate consistency after repeated queries, evidenced by a Spearman rho coefficient of 0.55 (P = 0.005). The chatbot appropriately described in-toeing as normal or spontaneously resolving in 62% of responses and consistently recommended evaluation by a health care provider in 100%.

CONCLUSION

The chatbot presented a serviceable, though not perfect, representation of the diagnosis and management of pediatric in-toeing while demonstrating a moderate level of reproducibility in its responses. ChatGPT's utility could be enhanced by improving readability and consistency and incorporating evidence-based guidelines.

LEVEL OF EVIDENCE

Level IV-diagnostic.

Tibial Spine Fractures in the Child and Adolescent Athlete: A Systematic Review and Meta-analysis

BACKGROUND

Tibial spine fractures (TSFs) are uncommon injuries that may result in substantial morbidity in children. A variety of open and arthroscopic techniques are used to treat these fractures, but no single standardized operative method has been identified.

PURPOSE

To systematically review the literature on pediatric TSFs to determine the current treatment approaches, outcomes, and complications.

STUDY DESIGN

Meta-analysis; Level of evidence, 4.

METHODS

A systematic review of the literature was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) guidelines using PubMed, Embase, and Cochrane databases. Studies evaluating treatment and outcomes of patients <18 years old were included. Patient demographic characteristics, fracture characteristics, treatments, and outcomes were abstracted. Descriptive statistics were used to summarize categorical and quantitative variables, and a meta-analytic technique was used to compare observational studies with sufficient data.

RESULTS

A total of 47 studies were included, totaling 1922 TSFs in patients (66.4% male) with a mean age of 12 years (range, 3-18 years). The operative approach was open reduction and internal fixation in 291 cases and arthroscopic reduction and internal fixation in 1236 cases; screw fixation was used in 411 cases and suture fixation, in 586 cases. A total of 13 nonunions were reported, occurring most frequently in Meyers and McKeever type III fractures (n = 6) and in fractures that were treated nonoperatively (n = 10). Arthrofibrosis rates were reported in 33 studies (n = 1700), and arthrofibrosis was present in 190 patients (11.2%). Range of motion loss occurred significantly more frequently in patients with type III and IV fractures (P < .001), and secondary anterior cruciate ligament (ACL) injury occurred most frequently in patients with type I and II fractures (P = .008). No statistically significant differences were found with regard to rates of nonunion, arthrofibrosis, range of motion loss, laxity, or secondary ACL injury between fixation methods (screw vs suture).

CONCLUSION

Despite variation in TSF treatment, good overall outcomes have been reported with low complication rates in both open and arthroscopic treatment and with both screw and suture fixation. Arthrofibrosis remains a concern after surgical treatment for TSF, but no significant difference in incidence was found between the analysis groups. Larger studies are necessary to compare outcomes and form a consensus on how to treat and manage patients with TSFs.

Relationship Between Age and Pathology With Treatment of Pediatric and Adolescent Discoid Lateral Meniscus: A Report From the SCORE Multicenter Database

BACKGROUND

Surgical treatment options of discoid lateral meniscus in pediatric patients consist of saucerization with or without meniscal repair, meniscocapular stabilization, and, less often, subtotal meniscectomy.

PURPOSE

To describe a large, prospectively collected multicenter cohort of discoid menisci undergoing surgical intervention, and further investigate corresponding treatment of discoid menisci.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A multicenter quality improvement registry (16 institutions, 26 surgeons), Sports Cohort Outcomes Registry, was queried. Patient characteristics, discoid type, presence and type of intrasubstance meniscal tear, peripheral rim instability, repair technique, and partial meniscectomy/debridement beyond saucerization were reviewed. Discoid meniscus characteristics were compared between age groups (<14 and >14 years old), based on receiver operating characteristic curve, and discoid morphology (complete and incomplete).

RESULTS

In total, 274 patients were identified (mean age, 12.4 years; range, 3-18 years), of whom 55.6% had complete discoid. Meniscal repairs were performed in 55.1% of patients. Overall, 48.5% of patients had rim instability and 36.8% had >1 location of peripheral rim instability. Of the patients, 21.5% underwent meniscal debridement beyond saucerization, with 8.4% undergoing a subtotal meniscectomy. Patients <14 years of age were more likely to have a complete discoid meniscus (P < .001), peripheral rim instability (P = .005), and longitudinal tears (P = .015) and require a meniscal repair (P < .001). Patients ≥14 years of age were more likely to have a radial/oblique tear (P = .015) and require additional debridement beyond the physiologic rim (P = .003). Overall, 70% of patients <14 years of age were found to have a complete discoid meniscus necessitating saucerization, and >50% in this young age group required peripheral stabilization/repair.

CONCLUSION

To preserve physiological "normal" meniscus, a repair may be indicated in >50% of patients <14 years of age but occurred in <50% of those >14 years. Additional resection beyond the physiological rim may be needed in 15% of younger patients and 30% of those aged >14 years.

Medial meniscal posterior horn tears and ramp lesions in pediatric patients: lessons learned

Meniscal injuries are increasingly reported in pediatric patients due to early sports participation and are commonly encountered during anterior cruciate ligament reconstruction. Preoperative identification of meniscal tears is crucial, particularly when involving the posteromedial meniscocapsular junction (ramp lesion). MRI plays an important role in detecting this particular type of meniscal injury. Consequently, pediatric radiologists should be aware of particular MRI findings related to ramp lesions including the presence of a medial meniscal tear, peripheral meniscal irregularity, meniscocapsular junctional fluid-like signal intensity, and capsular ligament tears. Thus, we illustrate the lessons we have learned from our institutional multidisciplinary arthroscopic-MR correlation conference for retrospectively identified posterior horn medial meniscal tears and ramp lesions.

Anterior Displacement of Tibial Spine Fractures: Does Anatomic Reduction Matter?

Background

Operative treatment of displaced tibial spine fractures consists of fixation and reduction of the fragment in addition to restoring tension of the anterior cruciate ligament.

Purpose

To determine whether residual displacement of the anterior portion of a tibial spine fragment affects the range of motion (ROM) or laxity in operatively and nonoperatively treated patients.

Study Design

Cohort study; Level of evidence, 3.

Methods

Data were gathered from 328 patients younger than 18 years who were treated for tibial spine fractures between 2000 and 2019 at 10 institutions. ROM and anterior lip displacement (ALD) measurements were summarized and compared from pretreatment to final follow-up. ALD measurements were categorized as excellent (0 to <1 mm), good (1 to <3 mm), fair (3 to 5 mm), or poor (>5 mm). Posttreatment residual laxity and arthrofibrosis were assessed.

Results

Overall, 88% of patients (290/328) underwent operative treatment. The median follow-up was 8.1 months (range, 3-152 months) for the operative group and 6.7 months (range, 3-72 months) for the nonoperative group. The median ALD measurement of the cohort was 6 mm pretreatment, decreasing to 0 mm after treatment (P < .001). At final follow-up, 62% of all patients (203/328) had excellent ALD measurements, compared with 5% (12/264) before treatment. Subjective laxity was seen in 11% of the nonoperative group (4/37) and 5% of the operative group (15/285; P = .25). Across the cohort, there was no association between final knee ROM and final ALD category. While there were more patients with arthrofibrosis in the operative group (7%) compared with the nonoperative group (3%) (P = .49), this was not different across the ALD displacement categories.

Conclusion

Residual ALD was not associated with posttreatment subjective residual laxity, extension loss, or flexion loss. The results suggest that anatomic reduction of a tibial spine fracture may not be mandatory if knee stability and functional ROM are achieved.

Fixation Strategy Does Not Affect Risk of Growth Disturbance After Surgical Treatment of Pediatric Tibial Spine Fracture

Purpose

To characterize growth abnormalities after surgical treatment of tibial spine fractures and to investigate risk factors for these abnormalities.

Methods

A retrospective analysis of children who underwent treatment of tibial spine fractures between January 2000 and January 2019 was performed, drawing from a multicenter cohort among 10 tertiary care children's hospitals. The entire cohort of surgically treated tibial spine fractures was analyzed for incidence and risk factors of growth disturbance. The cohort was stratified into those who were younger than the age of 13 years at the time of treatment in order to evaluate the risk of growth disturbance in those with substantial growth remaining. Patients with growth disturbance in this cohort were further analyzed based on age, sex, surgical repair technique, implant type, and preoperative radiographic measurements with χ2, t-tests, and multivariate logistic regression.

Results

Nine patients of 645 (1.4%) were found to have growth disturbance, all of whom were younger than 13 years old. Patients who developed growth disturbance were younger than those without (9.7 years vs 11.9 years, P = .019.) There was no association with demographic factors, fracture characteristics, surgical technique, hardware type, or anatomic placement (i.e., transphyseal vs physeal-sparing fixation) and growth disturbance.

Conclusions

In this study, we found an overall low incidence of growth disturbance after surgical treatment of tibial spine fractures. There was no association with surgical technique and risk of growth disturbance.

Level of Evidence

Level III, retrospective comparative study.

Interobserver and Intraobserver Agreement are Unsatisfactory When Determining Abstract Study Design and Level of Evidence

BACKGROUND

Understanding differences between types of study design (SD) and level of evidence (LOE) are important when selecting research for presentation or publication and determining its potential clinical impact. The purpose of this study was to evaluate interobserver and intraobserver reliability when assigning LOE and SD as well as quantify the impact of a commonly used reference aid on these assessments.

METHODS

Thirty-six accepted abstracts from the Pediatric Orthopaedic Society of North America (POSNA) 2021 annual meeting were selected for this study. Thirteen reviewers from the POSNA Evidence-Based Practice Committee were asked to determine LOE and SD for each abstract, first without any assistance or resources. Four weeks later, abstracts were reviewed again with the guidance of the Journal of Bone and Joint Surgery (JBJS) LOE chart, which is adapted from the Oxford Centre for Evidence-Based Medicine. Interobserver and intraobserver reliability were calculated using Fleiss' kappa statistic (k). χ2 analysis was used to compare the rate of SD-LOE mismatch between the first and second round of reviews.

RESULTS

Interobserver reliability for LOE improved slightly from fair (k=0.28) to moderate (k=0.43) with use of the JBJS chart. There was better agreement with increasing LOE, with the most frequent disagreement between levels 3 and 4. Interobserver reliability for SD was fair for both rounds 1 (k=0.29) and 2 (k=0.37). Similar to LOE, there was better agreement with stronger SD. Intraobserver reliability was widely variable for both LOE and SD (k=0.10 to 0.92 for both). When matching a selected SD to its associated LOE, the overall rate of correct concordance was 82% in round 1 and 92% in round 2 (P<0.001).

CONCLUSION

Interobserver reliability for LOE and SD was fair to moderate at best, even among experienced reviewers. Use of the JBJS/Oxford chart mildly improved agreement on LOE and resulted in less SD-LOE mismatch, but did not affect agreement on SD.

LEVEL OF EVIDENCE

Level II.

Is Nonoperative Treatment Appropriate for All Patients With Type 1 Tibial Spine Fractures? A Multicenter Study of the Tibial Spine Research Interest Group

Background:

Type 1 tibial spine fractures are nondisplaced or ≤2 mm–displaced fractures of the tibial eminence and anterior cruciate ligament (ACL) insertion that are traditionally managed nonoperatively with immobilization.

Hypothesis:

Type 1 fractures do not carry a significant risk of associated injuries and therefore do not require advanced imaging or additional interventions aside from immobilization.

Study Design:

Case series; Level of evidence, 4.

Methods:

We reviewed 52 patients who were classified by their treating institution with type 1 tibial spine fractures. Patients aged ≤18 years with pretreatment plain radiographs and ≤ 1 year of follow-up were included. Pretreatment imaging was reviewed by 4 authors to assess classification agreement among the treating institutions. Patients were categorized into 2 groups to ensure that outcomes represented classic type 1 fracture patterns. Any patient with universal agreement among the 4 authors that the fracture did not appear consistent with a type 1 classification were assigned to the type 1+ (T1+) group; all other patients were assigned to the true type 1 (TT1) group. We evaluated the rates of pretreatment imaging, concomitant injuries, and need for operative interventions as well as treatment outcomes overall and for each group independently.

Results:

A total of 48 patients met inclusion criteria; 40 were in the TT1 group, while 8 were in the T1+ group, indicating less than universal agreement in the classification of these fractures. Overall, 12 (25%) underwent surgical treatment, and 12 (25%) had concomitant injuries. Also, 8 patients required additional surgical management including ACL reconstruction (n = 4), lateral meniscal repair (n = 2), lateral meniscectomy (n = 1), freeing an incarcerated medial meniscus (n = 1), and medial meniscectomy (n = 1).

Conclusion:

The classification of type 1 fractures can be challenging. Contrary to prior thought, a substantial number of patients with these fractures (>20%) were found to have concomitant injuries. Overall, surgical management was performed in 25% of patients in our cohort.

Trends in Anterolateral Ligament Reconstruction and Lateral Extra-articular Tenodesis With ACL Reconstruction in Children and Adolescents

Background:

Anterolateral ligament reconstruction (ALLR) and lateral extra-articular tenodesis (LET) show promise in lowering the risk of rerupture after anterior cruciate ligament reconstruction (ACLR), but there are little data on surgeon practices and preferences in children and adolescents.

Purpose:

To quantify surgeon practices regarding ALLR and LET in the pediatric population.

Study Design:

Cross-sectional study.

Methods:

An electronic survey was administered to 87 surgeons in the Pediatric Research in Sports Medicine society. The questionnaire asked several questions about surgeon and practice characteristics as well as indications, preferences, and techniques for ALLR or LET in the context of primary and revision pediatric ACLR. Chi-square and Fisher exact tests were used to evaluate factors that affect surgical preferences.

Results:

A total of 63 surgeons completed the survey, of whom 62% performed ≥50 pediatric ACLRs annually; 56% sometimes performed anterolateral augmentation with primary ACLR, and 79% with revision ACLR. The most common indications for ALLR or LET in the primary setting were high-grade pivot shift, knee hyperextension, generalized laxity, and type of sports participation. Surgeons whose practice was >75% sports medicine were more likely to perform ALLR or LET with both primary and revision ACLR (P = .005 and P < .001, respectively). Those who had completed a sports medicine fellowship were more likely to perform these procedures than those with only pediatric orthopaedic training, in both primary (68% vs 36%; P = .01) and revision scenarios (92% vs 60%; P = .002). Of the 28 respondents who did not perform ALLR or LET with primary ACLR, 75% cited insufficient evidence as the reason. However, 96% of surgeons who did perform these procedures expressed interest in studying them prospectively, and 87% were willing to randomize patients.

Conclusion:

Findings indicated that 56% of pediatric sports surgeons sometimes perform anterolateral augmentation with primary ACLR and 79% with revision ACLR. Surgeons with sports medicine fellowship training or a mostly sports practice were more likely to perform these procedures. Insufficient evidence was the most common reason given by surgeons who did not perform anterolateral augmentation. However, there was substantial willingness to prospectively study and even randomize pediatric patients to assess the impact of ALLR or LET in this population.

What Are the Causes and Consequences of Delayed Surgery for Pediatric Tibial Spine Fractures? A Multicenter Study

Background:

The uncommon nature of tibial spine fractures (TSFs) may result in delayed diagnosis and treatment. The outcomes of delayed surgery are unknown.

Purpose:

To evaluate risk factors for, and outcomes of, delayed surgical treatment of pediatric TSFs.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

The authors performed a retrospective cohort study of TSFs treated surgically at 10 institutions between 2000 and 2019. Patient characteristics and preoperative data were collected, as were intraoperative information and postoperative complications. Surgery ≥21 days after injury was considered delayed based on visualized trends in the data. Univariate analysis was followed by purposeful entry multivariate regression to adjust for confounders.

Results:

A total of 368 patients (mean age, 11.7 ± 2.9 years) were included, 21.2% of whom underwent surgery ≥21 days after injury. Patients who experienced delayed surgery had 3.8 times higher odds of being diagnosed with a TSF at ≥1 weeks after injury (95% CI, 1.1-14.3; P = .04), 2.1 times higher odds of having seen multiple clinicians before the treating surgeon (95% CI, 1.1-4.1; P = .03), 5.8 times higher odds of having magnetic resonance imaging (MRI) ≥1 weeks after injury (95% CI, 1.6-20.8; P < .007), and were 2.2 times more likely to have public insurance (95% CI, 1.3-3.9; P = .005). Meniscal injuries were encountered intraoperatively in 42.3% of patients with delayed surgery versus 21.0% of patients treated without delay (P < .001), resulting in 2.8 times higher odds in multivariate analysis (95% CI, 1.6-5.0; P < .001). Delayed surgery was also a risk factor for procedure duration >2.5 hours (odds ratio, 3.3; 95% CI, 1.4-7.9; P = .006). Patients who experienced delayed surgery and also had an operation >2.5 hours had 3.7 times higher odds of developing arthrofibrosis (95% CI, 1.1-12.5; P = .03).

Conclusion:

Patients who underwent delayed surgery for TSFs were found to have a higher rate of concomitant meniscal injury, longer procedure duration, and more postoperative arthrofibrosis when the surgery length was >2.5 hours. Those who experienced delays in diagnosis or MRI, saw multiple clinicians, and had public insurance were more likely to have a delay to surgery.

Does Insurance Status Affect Treatment of Children With Tibial Spine Fractures?

BACKGROUND

Previous studies have reported disparities in orthopaedic care resulting from demographic factors, including insurance status. However, the effect of insurance on pediatric tibial spine fractures (TSFs), an uncommon but significant injury, is unknown.

PURPOSE

To assess the effect of insurance status on the evaluation and treatment of TSFs in children and adolescents.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

We performed a retrospective cohort study of TSFs treated at 10 institutions between 2000 and 2019. Demographic data were collected, as was information regarding pre-, intra-, and postoperative treatment, with attention to delays in management and differences in care. Surgical and nonsurgical fractures were included, but a separate analysis of surgical patients was performed. Univariate analysis was followed by purposeful entry multivariate regression to adjust for confounding factors.

RESULTS

Data were collected on 434 patients (mean ± SD age, 11.7 ± 3.0 years) of which 61.1% had private (commercial) insurance. Magnetic resonance imaging (MRI) was obtained at similar rates for children with public and private insurance (41.4% vs 41.9%, respectively; P≥ .999). However, multivariate analysis revealed that those with MRI performed ≥21 days after injury were 5.3 times more likely to have public insurance (95% CI, 1.3-21.7; P = .02). Of the 434 patients included, 365 required surgery. Similar to the overall cohort, those in the surgical subgroup with MRI ≥21 days from injury were 4.8 times more likely to have public insurance (95% CI, 1.2-19.6; P = .03). Children who underwent surgery ≥21 days after injury were 2.5 times more likely to have public insurance (95% CI, 1.1-6.1; P = .04). However, there were no differences in the nature of the surgery or findings at surgery. Those who were publicly insured were 4.1 times more likely to be immobilized in a cast rather than a brace postoperatively (95% CI, 2.3-7.4; P < .001).

CONCLUSION

Children with public insurance and a TSF were more likely to experience delays with MRI and surgical treatment than those with private insurance. However, there were no differences in the nature of the surgery or findings at surgery. Additionally, patients with public insurance were more likely to undergo postoperative casting rather than bracing.

Four Risk Factors for Arthrofibrosis in Tibial Spine Fractures: A National 10-Site Multicenter Study

BACKGROUND

Tibial spine fractures (TSFs) are relatively rare pediatric injuries. Postoperative arthrofibrosis remains the most common complication, with few studies having examined factors associated with its development.

PURPOSE

To identify risk factors for arthrofibrosis and required MUA or lysis of adhesions in the largest known cohort of patients with TSFs.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

This was a multicenter study of 249 patients ≤18 years old who had a TSF between January 2000 and February 2019. Patients were separated into cohorts based on whether they developed arthrofibrosis, defined as a 10° deficit in extension and/or 25° deficit in flexion at postoperative 3 months or a return to the operating room for manipulation under anesthesia (MUA) and/or lysis of adhesions.

RESULTS

A total of 58 (23.3%) patients developed postoperative arthrofibrosis, with 19 (7.6%) requiring a return to the operating room for MUA. Patients with arthrofibrosis were younger (mean ± SD, 11.3 ± 2.7 vs 12.3 ± 2.8 years; P = .029). They were more likely to have a nonsport, trauma-related injury (65.4% vs 32.1%; P < .001) and a concomitant ACL injury (10.3% vs 1.1%; P = .003). Those with arthrofibrosis had longer operative times (135.0 vs 114.8 minutes; P = .006) and were more likely to have been immobilized in a cast postoperatively (30.4% vs 16.6%; P = .043). In multivariate regression, concomitant anterior cruciate ligament (ACL) injury (odds ratio [OR], 20.0; P = .001), traumatic injury (OR, 3.8; P < .001), age <10 years (OR, 2.2; P = .049), and cast immobilization (OR, 2.4; P = .047) remained significant predictors of arthrofibrosis. Concomitant ACL injury (OR, 7.5; P = .030) was additionally predictive of a required return to the operating room for MUA.

CONCLUSION

Surgeons should be cognizant of arthrofibrosis risk in younger patients with concomitant ACL tears and traumatic injuries not resulting from athletics. Furthermore, postoperative immobilization in a cast should be avoided given the high risk of arthrofibrosis. Concomitant ACL injury is associated with a higher return to the operating room for MUA.

Genetic structure and admixture in sheep from terminal breeds in the United States

Selection for performance in diverse production settings has resulted in variation across sheep breeds worldwide. Although sheep are an important species to the United States, the current genetic relationship among many terminal sire breeds is not well characterized. Suffolk, Hampshire, Shropshire and Oxford (terminal) and Rambouillet (dual purpose) sheep (n = 248) sampled from different flocks were genotyped using the Applied Biosystems Axiom Ovine Genotyping Array (50K), and additional Shropshire sheep (n = 26) using the Illumina Ovine SNP50 BeadChip. Relationships were investigated by calculating observed heterozygosity, inbreeding coefficients, eigenvalues, pairwise Wright’s F_ST estimates and an identity by state matrix. The mean observed heterozygosity for each breed ranged from 0.30 to 0.35 and was consistent with data reported in other US and Australian sheep. Suffolk from two different regions of the United States (Midwest and West) clustered separately in eigenvalue plots and the rectangular cladogram. Further, divergence was detected between Suffolk from different regions with Wright’s F_ST estimate. Shropshire animals showed the greatest divergence from other terminal breeds in this study. Admixture between breeds was examined using admixture, and based on cross‐validation estimates, the best fit number of populations (clusters) was K = 6. The greatest admixture was observed within Hampshire, Suffolk, and Shropshire breeds. When plotting eigenvalues, US terminal breeds clustered separately in comparison with sheep from other locations of the world. Understanding the genetic relationships between terminal sire breeds in sheep will inform us about the potential applicability of markers derived in one breed to other breeds based on relatedness.

Pediatric Type II Tibial Spine Fractures: Addressing the Treatment Controversy With a Mixed-Effects Model

Background:

Tibial spine fractures, although relatively rare, account for a substantial proportion of pediatric knee injuries with effusions and can have significant complications. Meyers and McKeever type II fractures are displaced anteriorly with an intact posterior hinge. Whether this subtype of pediatric tibial spine fracture should be treated operatively or nonoperatively remains controversial. Surgical delay is associated with an increased risk of arthrofibrosis; thus, prompt treatment decision making is imperative.

Purpose:

To assess for variability among pediatric orthopaedic surgeons when treating pediatric type II tibial spine fractures.

Study Design:

Cross-sectional study.

Methods:

A discrete choice experiment was conducted to determine the patient and injury attributes that influence the management choice. A convenience sample of 20 pediatric orthopaedic surgeons reviewed 40 case vignettes, including physis-blinded radiographs displaying displaced fractures and a description of the patient’s sex, age, mechanism of injury, and predominant sport. Surgeons were asked whether they would treat the fracture operatively or nonoperatively. A mixed-effects model was then used to determine the patient attributes most likely to influence the surgeon’s decision, as well as surgeon training background, years in practice, and risk-taking behavior.

Results:

The majority of respondents selected operative treatment for 85% of the presented cases. The degree of fracture displacement was the only attribute significantly associated with treatment choice (P < .001). Surgeons were 28% more likely to treat the fracture operatively with each additional millimeter of displacement of fracture fragment. Over 64% of surgeons chose to treat operatively when the fracture fragment was displaced by ≥3.5 mm. Significant variation in surgeon’s propensity for operative treatment of this fracture was observed (P = .01). Surgeon training, years in practice, and risk-taking scores were not associated with the respondent’s preference for surgical treatment.

Conclusion:

There was substantial variation among pediatric orthopaedic surgeons when treating type II tibial spine fractures. The decision to operate was based on the degree of fracture displacement. Identifying current treatment preferences among surgeons given different patient factors can highlight current variation in practice patterns and direct efforts toward promoting the most optimal treatment strategies for controversial type II tibial spine fractures.

Sport Participation and Specialization Characteristics Among Pediatric Soccer Athletes

Background:

Soccer is an increasingly popular sport for children and adolescents in the United States. Little is known about participation patterns related to sport specialization.

Purpose:

To investigate soccer participation levels and sport specialization characteristics among youth soccer athletes.

Study Design:

Cross-sectional study.

Methods:

Adolescent athletes aged between 12 and 18 years completed an online survey addressing participant demographics, sports and soccer participation history, and level of specialization. Descriptive analyses characterized participation, while chi-square and Kruskal-Wallis tests assessed the influence of specialization, sex, and grade on survey variables.

Results:

Overall, 83.7% of 746 respondents participated in an organized soccer league outside of school, and 37% played in multiple leagues concurrently. Nearly three-quarters of respondents trained in soccer more than 8 months of the year, with those who participated in club soccer being more likely to train more than 8 months of the year. More respondents were classified as high specialization (37.5%), followed by moderate (35.6%) and low (28.6%) specialization. No differences between sexes were noted for level of specialization or quitting other sports to specialize in soccer, but male athletes were more likely to train more than 8 months per year compared with female athletes. Respondents in older grades (9th-10th and 11th-12th grades) were more likely to be highly specialized and quit other sports to focus on soccer. No differences between grade levels were found among respondents training more than 8 months per year.

Conclusion:

The study findings suggest that many youth soccer athletes participated in multiple teams or leagues at the same time and trained more than 8 months of the year. Characteristics including participation on a club team, level of specialization, and male sex were associated with a greater likelihood of exceeding the 8-month training recommendation.

Two cases of combined patellar tendon avulsion from the tibia and patella

Avulsion fractures of the inferior pole of the patella and proximal tibial apophysis are independently rare injuries. They occur in children due to the relative weakness of the apophyseal cartilage compared to the ligaments and tendons. The combination of these two fractures, is exceedingly rare, with only a few previously described cases in the literature. Due to the infrequent presentation of this injury, careful examination and consideration of advanced imaging is important for diagnosis and preoperative planning. Here we present two cases of combined sleeve fractures of the inferior pole of the patella and tibial apophysis, with discussion of the pathophysiology, classification, identification and management of the injury.

Closed and Open Reduction of Displaced Pediatric Lateral Condyle Humeral Fractures, a Study of Short-Term Complications and Postoperative Protocols

BACKGROUND

Displaced lateral condyle humeral fractures in children are treated operatively to maximize function and growth of the elbow. Traditionally an open approach is used for reduction of the fracture, but recent series have shown promising results with closed reduction. Percutaneous pins are typically used for fixation, no matter the reduction method. This retrospective review compares our experience with early complications after open and closed reduction of these fractures.

METHODS

We retrospectively reviewed charts and radiographs of operatively treated lateral condyle fractures. The Song and Jakob classification systems were utilized to determine fracture severity. High-grade displacement was defined as Song stage 4 and 5, or Jakob type 3. Data was analyzed by fracture type (high-grade or low-grade) and by treatment method to look for differences in complication rates and treatment differences. Complications were defined as delayed union and infection.

RESULTS

172 fractures were analyzed, 141 were treated open, and 31 were treated closed. There were no statistically significant differences in pin duration, total cast time, additional procedures, or short term complications between the open and closed treatment groups, or the high and low-grade fracture groups. High-grade fractures were more likely to be treated with open reduction (p<0.0001). Pin duration prior to removal was not associated with increased incidence of infection or delayed union.

CONCLUSIONS

Closed reduction and percutaneous pinning of lateral condyle fractures amenable to this treatment does not seem to require any changes in postoperative treatment or alter the incidence of early complications when compared to open procedures.

LEVEL OF EVIDENCE

IV.

National Trends in Operative Treatment of Pediatric Fractures in the Ambulatory Setting

This study evaluated the expanding role of freestanding ambulatory surgery centers in pediatric fracture care based on the only national ambulatory surgery database within the United States. Released by the Centers for Disease Control and Prevention in 1996 and again in 2006, these reports were used to estimate the volume of outpatient pediatric operative fracture care in the United States over a decade, based on International Classification of Diseases, Ninth Revision, Clinical Modification, procedure codes. Particular attention focused on the prevalence of open vs closed vs percutaneous fixation. The estimated number of pediatric patients who presented to outpatient facilities and required operative fracture care between 1996 and 2006 increased by 88%, from 74,577 ± 4663 to 140,152 ± 9138. During this time, the use of outpatient surgical services for pediatric fractures increased threefold, from 10% ± 1% in 1996 to 32% ± 2% in 2006. An even greater preference for freestanding ambulatory surgery centers was observed during this same time by a factor of 7, from 3% ± 1% to 21% ± 4%. Additionally, a trend toward higher volumes of open and percutaneous fixation in freestanding ambulatory surgery centers and not in hospital-associated outpatient centers was observed. This study showed the expanding role of freestanding ambulatory surgery centers in the surgical treatment of pediatric fractures based on data from the only national ambulatory surgery database in the United States. The proportion of open and percutaneous treatment vs closed reduction of fractures in these facilities also greatly increased. Further study is needed to evaluate clinical outcomes and determine which fractures are most appropriately treated in the ambulatory vs hospital setting.

Level of evidence gap in orthopedic research

Level of evidence is the most widely used metric for the quality of a publication, but instances exist in which a Level I study is neither feasible nor desirable. The goal of this study was to evaluate the level of evidence gap in current orthopedic research, which the authors defined as the disparity between the level of evidence that would be required to optimally answer the primary research question and the level of evidence that was actually used. Five orthopedic surgeons (K.D.B., J.B., J.A., S.D.M., W.N.S.) evaluated blinded articles from the first 6 months of 2010 in the Journal of Bone and Joint Surgery (American Volume) (JBJS-Am), classifying the study type and design and extracting a primary research question from each article. Each evaluator then defined the study type and method, along with the level of evidence that would ideally be used to address the primary research question. The level of evidence gap was then calculated by subtracting the actual level of evidence of the manuscript from the level of evidence of the idealized study. Of the 64 JBJS-Am manuscripts eligible for analysis, the average level of evidence was between Level II and III (mean, 2.73). The average level of evidence gap was 1.06 compared with the JBJS-Am-designated level of evidence and 1.28 compared with the evaluators' assessment. Because not all questions require Level I studies, level of evidence alone may not be the best metric for the quality of orthopedic surgery literature. Instead, the authors' concept of a level of evidence gap may be a better tool for assessing the state of orthopedic research publications.

Genome-wide association analysis for quantitative trait loci influencing Warner-Bratzler shear force in five taurine cattle breeds

We performed a genome-wide association study for Warner–Bratzler shear force (WBSF), a measure of meat tenderness, by genotyping 3360 animals from five breeds with 54 790 BovineSNP50 and 96 putative single-nucleotide polymorphisms (SNPs) within μ-calpain [HUGO nomenclature calpain 1, (mu/I) large subunit; CAPN1] and calpastatin (CAST). Within- and across-breed analyses estimated SNP allele substitution effects (ASEs) by genomic best linear unbiased prediction (GBLUP) and variance components by restricted maximum likelihood under an animal model incorporating a genomic relationship matrix. GBLUP estimates of ASEs from the across-breed analysis were moderately correlated (0.31–0.66) with those from the individual within-breed analyses, indicating that prediction equations for molecular estimates of breeding value developed from across-breed analyses should be effective for genomic selection within breeds. We identified 79 genomic regions associated with WBSF in at least three breeds, but only eight were detected in all five breeds, suggesting that the within-breed analyses were underpowered, that different quantitative trait loci (QTL) underlie variation between breeds or that the BovineSNP50 SNP density is insufficient to detect common QTL among breeds. In the across-breed analysis, CAPN1 was followed by CAST as the most strongly associated WBSF QTL genome-wide, and associations with both were detected in all five breeds. We show that none of the four commercialized CAST and CAPN1SNP diagnostics are causal for associations with WBSF, and we putatively fine-map the CAPN1 causal mutation to a 4581-bp region. We estimate that variation in CAST and CAPN1 explains 1.02 and 1.85% of the phenotypic variation in WBSF respectively.

Genome-wide association analysis for feed efficiency in Angus cattle

Estimated breeding values for average daily feed intake (AFI; kg/day), residual feed intake (RFI; kg/day) and average daily gain (ADG; kg/day) were generated using a mixed linear model incorporating genomic relationships for 698 Angus steers genotyped with the Illumina BovineSNP50 assay. Association analyses of estimated breeding values (EBVs) were performed for 41 028 single nucleotide polymorphisms (SNPs), and permutation analysis was used to empirically establish the genome-wide significance threshold (P < 0.05) for each trait. SNPs significantly associated with each trait were used in a forward selection algorithm to identify genomic regions putatively harbouring genes with effects on each trait. A total of 53, 66 and 68 SNPs explained 54.12% (24.10%), 62.69% (29.85%) and 55.13% (26.54%) of the additive genetic variation (when accounting for the genomic relationships) in steer breeding values for AFI, RFI and ADG, respectively, within this population. Evaluation by pathway analysis revealed that many of these SNPs are in genomic regions that harbour genes with metabolic functions. The presence of genetic correlations between traits resulted in 13.2% of SNPs selected for AFI and 4.5% of SNPs selected for RFI also being selected for ADG in the analysis of breeding values. While our study identifies panels of SNPs significant for efficiency traits in our population, validation of all SNPs in independent populations will be necessary before commercialization.

A genome scan for quantitative trait loci influencing carcass, post-natal growth and reproductive traits in commercial Angus cattle

To gain insight into the number of loci of large effect that underlie variation in cattle, a quantitative trait locus (QTL) scan for 14 economically important traits was performed in two commercial Angus populations using 390 microsatellites, 11 single nucleotide polymorphisms (SNPs) and one duplication loci. The first population comprised 1769 registered Angus bulls born between 1955 and 2003, with Expected Progeny Differences computed by the American Angus Association. The second comprised 38 half-sib families containing 1622 steers with six post-natal growth and carcass phenotypes. Linkage analysis was performed by half-sib least squares regression with gridqtl or Bayesian Markov chain Monte Carlo analysis of complex pedigrees with loki. Of the 673 detected QTL, only 118 have previously been reported, reflecting both the conservative approach to QTL reporting in the literature, and the more liberal approach taken in this study. From 33 to 71% of the genetic variance and 35 to 56% of the phenotypic variance in each trait was explained by the detected QTL. To analyse the effects of 11 SNPs and one duplication locus within candidate genes on each trait, a single marker analysis was performed by fitting an additive allele substitution model in both mapping populations. There were 53 associations detected between the SNP/duplication loci and traits with -log(10) P(nominal) ≥ 4.0, where each association explained 0.92% to 4.4% of the genetic variance and 0.01% to 1.86% of the phenotypic variance. Of these associations, only six SNP/duplication loci were located within 8 cM of a QTL peak for the trait, with two being located at the QTL peak: SST_DG156121:c.362A>G for ribeye muscle area and TG_X05380:c.422C>T for calving ease. Strong associations between several SNP/duplication loci and trait variation were obtained in the absence of any detected linked QTL. However, we reject the causality of several commercialized DNA tests, including an association between TG_X05380:c.422C>T and marbling in Angus cattle.

Identification of loci associated with tolerance to Johne's disease in Holstein cattle

Johne's disease, caused by Mycobacterium avium subspecies paratuberculosis (Map), is a fatal disease in cattle. The objective of this study was to identify loci associated with tolerance in cows infected with Map. Tolerance was defined as a cow's fitness at a given level of Map infection intensity. Fitness was measured by Map faecal cultures, and Map infection intensity was measured by culturing four gut tissues. The quantitative phenotype of tolerance was defined by numerical indexes of cultures of peak (peak tolerance, PT) and average (average tolerance, AT) faecal and tissue Map from 245 Holstein cows. The categorical phenotype was defined as: ≥ 100 cfu Map tissue infection, and faecal shedding ≥ 75 cfu (intolerant) or <10 cfu (tolerant cows). In 94 cows, Map was identified in ≥ 1 tissue, including 44 cows with ≥ 100 Map tissue cfu and 36 with ≥ 1 faecal cfu. A genome-wide association analysis was performed after filtering, leaving genotypes for 45,789 SNPs in 90 animals for the quantitative phenotype and 16 cases and 25 controls for the categorical analysis of tolerance. rs41748405:A>C (BTA15) was associated with PT (P = 1.12 × 10(-7)) and AT (P = 2.17 × 10(-6)). Associations were identified with PT and adjacent SNPs ss61512613:A>G and ss61530518:A>G (BTA6) (P < 3.0 × 10(-5)), and with AT for ss61469568:A>G (BTA 2) (P = 3.3 × 10(-5)) and ss86284768:A>G (BTA1) (P = 3.31 × 10(-5)). For the categorical phenotype, an association was found with ss8632653:A>G (BTA6) (P < 5.0 × 10(-5)). This is the first study to identify loci associated with tolerance to Johne's disease.

A truncated retrotransposon disrupts the GRM1 coding sequence in Coton de Tulear dogs with Bandera's neonatal ataxia

BACKGROUND

Bandera's neonatal ataxia (BNAt) is an autosomal recessive cerebellar ataxia that affects members of the Coton de Tulear dog breed.

OBJECTIVE

To identify the mutation that causes BNAt.

ANIMALS

The study involved DNA from 112 Cotons de Tulear (including 15 puppies with signs of BNAt) and 87 DNA samples from dogs of 12 other breeds.

METHODS

The BNAt locus was mapped with a genome-wide association study (GWAS). The coding exons of positional candidate gene GRM1, which encodes metabotropic glutamate receptor 1, were polymerase chain reaction (PCR)-amplified and resequenced. A 3-primer PCR assay was used to genotype individual dogs for a truncated retrotransposon inserted into exon 8 of GRM1.

RESULTS

The GWAS indicated that the BNAt locus was in a canine chromosome 1 region that contained candidate gene GRM1. Resequencing this gene from BNAt-affected puppies indicated that exon 8 was interrupted by the insertion of a 5'-truncated retrotransposon. All 15 BNAt-affected puppies were homozygous for the insert, whereas all other Cotons de Tulear were heterozygotes (n = 43) or homozygous (n = 54) for the ancestral allele. None of the 87 dogs from 12 other breeds had the insertion allele.

CONCLUSIONS AND CLINICAL IMPORTANCE

BNAt is caused by a retrotransposon inserted into exon 8 of GRM1. A DNA test for the GRM1 retrotransposon insert can be used for genetic counseling and to confirm the diagnosis of BNAt.

Genomic tools for characterizing monogenic and polygenic traits in ruminants--using the bovine as an example

Next generation sequencing platforms have democratized genome sequencing. Large genome centers are no longer required to produce genome sequences costing millions. A few lanes of paired-end sequence on an Illumina Genome Analyzer, costing < $10,000, will produce more sequence than generated only a few years ago to produce the human and cow assemblies. The de novo assembly of large numbers of short reads into a high-quality whole-genome sequence is now technically feasible and will allow the whole genome sequencing and assembly of a broad spectrum of ruminant species. Next-generation sequencing instruments are also proving very useful for transcriptome or resequencing projects in which the entire RNA population produced by a tissue, or the entire genomes of individual animals are sequenced, and the produced reads are aligned to a reference assembly. We have used this strategy to examine gene expression differences in tissues from cattle differing in feed efficiency, to perform genome-wide single nucleotide polymorphism discovery for the construction of ultrahigh-density genotyping assays, and in combination with genome-wide association analysis, for the identification of mutations responsible for Mendelian diseases. The new 800K SNP bovine genotyping assays possess the resolution to map trait associations to the locations of individual genes and the 45 million polymorphisms identified in > 180X genome sequence coverage on over 200 animals can be queried to identify the polymorphisms present within positional candidate genes. These new tools should rapidly allow the identification of genes and mutations underlying variation in cattle production and reproductive traits.

A whole genome association analysis identifies loci associated with Mycobacterium avium subsp. paratuberculosis infection status in US holstein cattle

The purpose of this study was to identify loci associated with Mycobacterium avium subspecies paratuberculosis (Map) infection status in US Holsteins using the Illumina BovineSNP50 BeadChip whole genome single nucleotide polymorphism (SNP) assay. Two hundred forty-five cows from dairies in New York, Pennsylvania and Vermont enrolled in longitudinal herd studies between January 1999 and November 2007 were assessed for the presence of Map in both faecal and tissue samples. An animal was considered tissue infected if any sample contained at least one colony forming unit of Map per gram of tissue (CFU/g) and the same definition was employed for faecal samples. Each animal was genotyped with the Illumina BovineSNP50 BeadChip and after quality assurance filtering, 218 animals and 45 683 SNPs remained. We sought to identify loci associated with four different case/control classifications: presence of Map in the tissue, presence of Map in faeces, presence of Map in both tissue and faeces and presence of Map in tissue but not faeces. A case-control genome wide association study was conducted to test the four different classifications of Map infection status (cases) when compared with a Map-negative control group (control). Regions on chromosomes 1, 5, 7, 8, 16, 21 and 23 were identified with moderate significance (P < 5 x 10(-5)). Two regions, one on chromosome 3 (near EDN2) and another on chromosome 9 (no positional gene candidates), were identified with a high level of association to the presence of Map in tissue and both tissue and faeces respectively (P < 5 x 10(-7), genome-wide Bonferonni P < 0.05).

Linkage disequilibrium and signatures of selection on chromosomes 19 and 29 in beef and dairy cattle

The objective of this study was to quantify the extent of linkage disequilibrium (LD) on bovine chromosomes 19 and 29 and to study the pattern of selection signatures in beef and dairy breeds (Angus and Holstein) of Bos taurus. The extent of LD was estimated for 370 and 186 single nucleotide polymorphism markers on BTA19 and 29 respectively using the square of the correlation coefficient (r(2)) among alleles at pairs of loci. A comparison of the extent of LD found that the decline of LD followed a similar pattern in both breeds. We observed long-range LD and found that LD dissipates to background levels at a locus separation of about 20 Mb on both chromosomes. Along each chromosome, patterns of LD were variable in both breeds. We find that a minimum of 30 000 informative and evenly spaced markers would be required for whole-genome association studies in cattle. In addition, we have identified chromosomal regions that show some evidence of selection for economically important traits in Angus and Holstein cattle. The results of this study are of importance for the design and application of association studies.

Construction of bovine whole-genome radiation hybrid and linkage maps using high-throughput genotyping

High-density whole-genome maps are essential for ordering genes or markers and aid in the assembly of genome sequence. To increase the density of markers on the bovine radiation hybrid map, and hence contribute to the assembly of the bovine genome sequence, an Illumina® BeadStation was used to simultaneously type large numbers of markers on the Roslin-Cambridge 3000 rad bovine–hamster whole-genome radiation hybrid panel (WGRH₃₀₀₀). In five multiplex reactions, 6738 sequence tagged site (STS) markers were successfully typed on the WGRH₃₀₀₀ panel DNA. These STSs harboured SNPs that were developed as a result of the bovine genome sequencing initiative. Typically, the most time consuming and expensive part of creating high-density radiation hybrid (RH) maps is genotyping the markers on the RH panel with conventional approaches. Using the method described in this article, we have developed a high-density whole-genome RH map with 4690 loci and a linkage map with 2701 loci, with direct comparison to the bovine whole-genome sequence assembly (Btau_2.0) in a fraction of the time it would have taken with conventional typing and genotyping methods.

Assessment of complications of distal radius fractures and development of a complication checklist

The purposes of this study were to determine the overall incidence of distal radius fracture (DRF) complications, determine the incidence and types of DRF complications in a consecutive cohort of 250 patients with DRFs, describe DRF complications reported by patients compared with those reported by physicians, and formulate a DRF complication checklist to improve recording of DRF complications. We found that the overall complication rates vary widely (6% to 80%). Physician-reported complication data were collected for 236 patients, and a physician-reported complication rate of 27% was determined. A patient-reported complication rate of 21% was found for 207 patients whose patient-reported data were collected. We also noted that patients and physicians assess DRF complications differently: patients are more focused on symptoms than diagnoses. A DRF complication checklist was developed to improve prospective data collection. The checklist includes a classification for all DRF complications and allows for assessment of severity of each complication.