MRI of the Spine in Patients who Toe Walk: Is There a Role?

BACKGROUND: Little is known about the prevalence of intraspinal pathology in children who toe walk, but magnetic resonance imaging (MRI) may be part of the diagnostic workup. The purpose of this study was to examine the role of MRI for children who toe walk with a focus on the rate of positive findings and associated neurosurgical interventions performed for children with said MRI findings. METHODS: A single-center tertiary hospital database was queried to identify a cohort of 118 subjects with a diagnosis of toe walking who underwent spinal MRI during a 5-year period. Patient and MRI characteristics were summarized and compared between subjects with a major abnormality, minor abnormality, or no abnormality on MRI using multivariable logistic regression. Major MRI abnormalities included those with a clear spinal etiology, such as fatty filum, tethered cord, syrinx, and Chiari malformation, while minor abnormalities had unclear associations with toe walking. RESULTS: The most common primary indications for MRI were failure to improve with conservative treatment, severe contracture, and abnormal reflexes. The prevalence of major MRI abnormalities was 25% (30/118), minor MRI abnormalities was 19% (22/118), and normal MRI was 56% (66/118). Patients with delayed onset of toe walking were significantly more likely to have a major abnormality on MRI ( P =0.009). The presence of abnormal reflexes, severe contracture, back pain, bladder incontinence, and failure to improve with conservative treatment were not significantly associated with an increased likelihood of major abnormality on MRI. Twenty-nine (25%) subjects underwent tendon lengthening, and 5 (4%) underwent neurosurgical intervention, the most frequent of which was detethering and sectioning of fatty filum. CONCLUSIONS: Spinal MRI in patients who toe walk has a high rate of major positive findings, some of which require neurosurgical intervention. The most significant predictor of intraspinal pathology was the late onset of toe walking after the child had initiated walking. MRI of the spine should be considered by pediatric orthopedic surgeons in patients with toe walking who present late with an abnormal clinical course. LEVEL OF EVIDENCE: Level III Retrospective Comparative Study.

Pediatric Orthopaedic Venous Thromboembolism: A Systematic Review Investigating Incidence, Risk Factors, and Outcome.

Background: There is growing evidence of increased venous thromboembolism (VTE) incidence in children with trauma or infection. The purpose of this study was to conduct a systematic review of existing literature related to VTE in the pediatric orthopaedic population, to estimate the overall incidence of VTE and identify risk factors associated with this condition. Methods: A systematic review of the available literature was performed to identify articles that described VTE in pediatric orthopaedic surgery or admission. Literature queries were performed to identify articles published from 1980 to 2021 that included patients ≤21 years of age. A stepwise search strategy of 5 electronic databases yielded 1,426 articles, which were filtered by 2 reviewers to identify 30 articles for full-text review. The primary aim was to determine the rate of VTE, and the secondary aim was to identify risk factors for VTE. The pooled incidence of VTE was estimated and reported in cases per 10,000. Studies were stratified by study size, by trauma versus elective surgery, and by orthopaedic subspecialty. Results: The 30 articles reported 3,113 VTE events in 2,467,764 pediatric patients (including those with non-orthopaedic conditions), for a pooled VTE incidence of 20 events (95% confidence interval [CI] = 10.8 to 37.2) per 10,000. Four of the studies were excluded for incomplete data or high heterogeneity. The remaining 26 studies had 850,268 orthopaedic patients with 1,108 cases of VTE, for a pooled VTE incidence of 16.6 events (95% CI = 9.1 to 30.5) per 10,000. Studies with <10,000 patients and those involving a diagnosis of trauma had the highest VTE incidence when stratification was performed. The most frequently analyzed risk factors in 15 available studies included age, sex, obesity/body mass index, type of surgery, and use of a central venous catheter. Conclusions: This systematic review indicated that the risk of VTE associated with pediatric orthopaedic surgery or admission remains low, at <17 events per 10,000 cases. However, orthopaedic surgeons should be aware of the most common risk factors associated with pediatric orthopaedic VTE and should pay special attention to traumatic etiologies, as these yielded the highest incidence. Levels of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Protocol and validity testing of femoroacetabular posterior translation with dynamic hip ultrasonography.

OBJECTIVE: To describe femoroacetabular posterior translation (FAPT) using dynamic hip ultrasonography (DHUS), and to determine the inter- and intra-rater reliability of hip ultrasound measurements of FAPT. MATERIALS AND METHODS: The study design was a feasibility study of 13 healthy young adults (26 hips) using test-retest analysis. The data was collected prospectively over a 2-week time period. Three DHUS measurements (posterior neutral (PN), flexion, adduction, and internal rotation (PFADIR), and stand and load (PStand) were measured by four independent raters (2 senior who divided the cohort, 1 intermediate, 1 junior) at two time points for bilateral hips of each participant. Reliability was assessed by calculating the intraclass correlation coefficient (ICC) along with 95% confidence intervals (CIs) for each rater and across all raters. RESULTS: A total of 468 US scans were completed. The mean age of the cohort was 25.7 years (SD 5.1 years) and 54% were female. The inter-rater reliability was excellent for PFADIR (ICC 0.85 95% CI 0.76-0.91), good for PN (ICC 0.69 95% CI 0.5-0.81), and good for PStand (ICC 0.72 95% CI 0.55-0.83). The intra-rater reliability for all raters was good for PFADIR (ICC 0.60 95% CI 0.44-0.73), fair for PN (ICC 0.42 95% CI 0.21-0.59), and fair for PStand (ICC 0.42 95% CI 0.22-0.59). CONCLUSION: This is the first study to present a protocol using dynamic ultrasonography to measure FAPT. DHUS measure for FAPT was shown to be reliable across raters with varying levels of ultrasound experience.

Anterior Distal Femoral Hemiepiphysiodesis in Children With Fixed Knee Flexion Deformities: Does Screw Position Matter?

BACKGROUND: Anterior distal femoral hemiepiphysiodesis (ADFH) using 2 percutaneous screws is an effective technique for the treatment of fixed knee flexion deformities in children with neuromuscular disorders. The role of sagittal screw position on the outcome of the procedure is unknown. METHODS: This is a retrospective case series of patients who underwent ADFH at a single pediatric hospital from 2013 to 2020. Radiographs were evaluated for sagittal screw position and the associated change in lateral distal femoral physeal angle over time. The position of the 2 screws was classified as either being both in the anterior third of the physis (AA), one screw in the anterior third and the other screw in the middle third (AM), or both screws in the middle third of the physis (MM). RESULTS: The study population included 68 knees in 36 patients. The mean physeal angle at the time of surgery was 93 degrees (SD 4.0 degrees), which increased to 102.4 degrees (SD 5.7 degrees) at 12 months, for a change of 9.4 degrees ( P <0.001). At 24 months, the mean physeal angle was 104.6 degrees (SD 6.3 degrees) for a further change of 2.9 degrees ( P <0.001). When stratified by screw position all screw configurations resulted in an increase in the physeal angle at 12 months. At the 24-month follow-up, the physeal angle in knees with AA screws continued to increase another 3.5 degrees ( P <0.05), there was a minimal change in knees with AM screws (1.47°, P >0.05) and knees with MM screws saw a reversal of physeal angle change (-7.1 degrees, P <0.05). CONCLUSIONS: ADFH using percutaneous screws results in an increase in the lateral distal femoral physeal angle. The rate of correction is largest in the first 12 months after the procedure. As such, this procedure should be considered in patients with less than 2 years of growth remaining. However, initial screw positioning influences the amount of change over time, and close postoperative surveillance until physeal closure is essential for all patients. LEVEL OF EVIDENCE: Level IV-retrospective case series.

The Efficacy of a Mental Skills Training Course for Collegiate Athletes.

CONTEXT: Psychological skills training improves performance in athletes. However, few studies have looked at the efficacy and satisfaction of mental skills training programs for collegiate athletes. OBJECTIVE: We aimed to evaluate satisfaction of collegiate athletes with a 6-session mental skills course, and to assess changes in mental toughness and coping skills before and after the course. DESIGN: Prospective cohort study following collegiate female athletes through a 6-session mental skills course. SETTING: Division 1 collegiate athletic teams. PATIENTS/PARTICIPANTS: 54 Division I female athletes (mean age =19.8) participated in the program and 42 (77.7 %) completed pre-course assessments, which subsequent evaluations were matched to. MAIN OUTCOME MEASURES: The Athletic Coping Skills Inventory (ACSI, range=0-84) and Mental Toughness Index (MTI, range=8-56) assessed coping skills and mental toughness pre-course, immediate post-course and 4-month post course. Satisfaction was assessed on a 10-point scale. RESULTS: For participants with paired pre- and immediate post-course data (n=37, 68.5%), MTI scores improved by a mean 2.6 points (95% CI=1.1-4.1; p=0.001) and ACSI scores improved by a mean 4.0 points (95% CI=0.6-7.4; p=0.02). At four-month follow-up (n=25, 46.2%), no change was detected from pre-course in mean MTI score (p=0.72), but there was a significant increase of 3.4 points in mean ACSI (95% CI=0.4-6.4; p=0.03). Overall satisfaction had a median score of 9/10 (IQR, 8-10) at post-course, and eighteen participants (48.6%) shared positive free-text comments regarding course delivery, content, and impact. No negative feedback was reported. CONCLUSIONS: Mental toughness and coping skills scores significantly improved at post-course assessment, with coping skills scores maintaining their effect at four months. The improvements identified spark the question of the potential impact of mental skills training programs when studied in larger athlete populations or over more sustained periods of time. Athletes reported being highly satisfied with course content and reported overall positive experiences.

Intrarater and Interrater Reliability of Radiographic Characteristics in Skeletally Immature Patients With Anterior Cruciate Ligament Tears: A PLUTO Study Group Reliability Study.

BACKGROUND: Radiographic measurements of limb alignment in skeletally immature patients with anterior cruciate ligament (ACL) tears are frequently used for surgical decision-making, preoperative planning, and postoperative monitoring of skeletal growth. However, the interrater and intrarater reliability of these radiographic characteristics in this patient population is not well documented. HYPOTHESIS: Excellent reliability across 4 raters will be demonstrated for all digital measures of length, coronal plane joint orientation angles, mechanical axis, and tibial slope in skeletally immature patients with ACL tears. STUDY DESIGN: Cohort study (diagnosis). METHODS: Three fellowship-trained orthopaedic surgeons and 1 medical student performed 2 rounds of radiographic measurements on digital imaging (lateral knee radiographs and long-leg radiographs) of skeletally immature patients with ACL tears. Intrarater and interrater reliability for continuous radiographic measurements was assessed with intraclass correlation coefficients (ICCs) across 4 raters with 95% CIs for affected and unaffected side measurements. Interrater reliability analysis used an ICC (2, 4) structure and intrarater reliability analysis used an ICC (2, 1) structure. A weighted kappa coefficient was calculated for ordinal variables along with 95% CIs for both interrater and intrarater reliability. Agreement statistic interpretations are based on scales described by Fleiss, and Cicchetti and Sparrow: <0.40, poor; 0.40 to 0.59, fair; 0.60 to 0.74, good; and >0.74, excellent. RESULTS: Radiographs from a convenience sample of 43 patients were included. Intrarater reliability was excellent for nearly all measurements and raters. Interrater reliability was also excellent for nearly all reads for all measurements. CONCLUSION: Radiographic reliability of long-leg radiographs and lateral knee x-rays in skeletally immature children with ACL tears is excellent across nearly all measures and raters and can be obtained and interpreted as reliable and reproducible means to measure limb length and alignment. LEVEL OF EVIDENCE: Level III.

Outcomes of Adolescent T-condylar Fractures: Kids Do Not Always Make You Look Good.

BACKGROUND: Optimal treatment for pediatric and adolescent T-condylar fractures remains poorly understood. We sought to assess how functional outcomes and range of motion (ROM) after surgical fixation of T-condylar fractures are affected by patient and surgical factors. METHODS: This is a retrospective cohort study of 52 patients with operatively treated T-condylar fractures at a single tertiary pediatric referral center between 2003 and 2021. All patients younger than 18 at the time of injury with a radiographically confirmed diagnosis were included. RESULTS: Fifty-two T-condylar fractures were included, with a mean patient age of 12.9 years (SD, 2.8). The cohort was 65% male. Nine (19%) fractures were open, 46% (24/52) were AO type C2, and 33% (17/52) occurred in skeletally mature individuals. The surgical approach was through olecranon osteotomy in 29% (15/52) of patients, and fixation included anatomically specific plates and screws in 42% (22/52) of patients. In our cohort, 46% (24/52) achieved good outcomes based on Jarvis ROM criteria and 42% (22/52) achieved good to excellent results based on Roberts functional criteria. The median loss of ROM was 58 degrees at 6 weeks, 20 degrees at 3 and 6 months, and 8 degrees at 1 year postoperatively. We observed a complication rate of 54% (28/52). Patients undergoing adult-type plate fixation had better postoperative range of motion at 6 weeks (ROM loss 52 vs. 80 degrees, P =0.03) and 3 months (10 vs. 35 degrees P =0.004) compared with pediatric-type fixation and trended towards better functional outcomes. We did not identify significant differences in functional outcome scores or complication rates with respect to surgical approach or skeletal maturity. CONCLUSIONS: Surgical fixation of pediatric and adolescent T-condylar fractures achieved a good to excellent functional outcome in only a minority of patients (46% Jarvis / 42% Roberts) with a high rate of postoperative complications (54%). Future work is needed to elucidate optimal treatment to minimize complications and achieve the best functional outcomes in these challenging fractures. LEVEL OF EVIDENCE: Level-IV.

The Incidence of Posttraumatic Stress Symptoms in Children.

OBJECTIVE: To determine the incidence of posttraumatic stress disorder (PTSD) symptoms and risk factors for their development in children and adolescents undergoing orthopaedic surgery for trauma. DESIGN: Prospective cohort study. SETTING: Level-1 trauma center. PATIENTS: Children (8 to 18), undergoing surgery for orthopaedic trauma. INTERVENTION: Upper and lower extremity surgery for orthopaedic trauma. MAIN OUTCOME MEASUREMENTS: PTSD symptoms at postoperative follow-up as determined by the Child PTSD Symptom Scale (CPSS). RESULTS: A total of 176 children with an average age at surgery of 13 years (8 to 18.8 years) participated in the study. Twenty-six subjects had high levels of PTSD symptoms (15%; 95% CI = 10.0 to 21.1%). Univariable and multivariable analyses determined that female sex (OR 2.63, 95% CI = 1.06 to 6.67, P = 0.04), older age at surgery (OR 1.25, 95% CI = 1.04 to 1.51, P = 0.02), and undergoing a previous surgery (OR 2.86, 95% CI = 1.06 to 7.73, P = 0.04) were all associated with increased PTSD risk. CONCLUSIONS: Children and adolescents experience a high level of PTSD symptoms (15%) after surgery for orthopaedic trauma. Clinicians should be aware of PTSD symptoms in children and adolescents after surgery for orthopaedic injuries and use comprehensive screening to facilitate timely intervention and treatment. LEVEL OF EVIDENCE: II.

Transarticular Versus Retroarticular Drilling of Stable Osteochondritis Dissecans of the Knee: A Prospective Multicenter Randomized Controlled Trial by the ROCK Group.

BACKGROUND: When stable osteochondritis dissecans (OCD) lesions of the femoral condyle in a skeletally immature patient fail to heal with nonoperative methods, the standard of care treatment is condylar OCD drilling. Two primary OCD drilling techniques have been described, but no prospective studies have compared their relative effectiveness. PURPOSE/HYPOTHESIS: The purpose of this study was to compare the healing and function after transarticular drilling (TAD) with that after retroarticular drilling (RAD). It was hypothesized that there would be no difference in rate or time to healing, rate or time to return to sports, patient-reported outcomes (PROs), or secondary OCD-related surgery. STUDY DESIGN: Randomized controlled clinical trial; Level of evidence, 1. METHODS: Skeletally immature patients with magnetic resonance imaging-confirmed stable OCD lesions of the medial femoral condyle who did not demonstrate substantial healing after a minimum of 3 months of nonoperative treatment were prospectively enrolled by 1 of 17 surgeon-investigators at 1 of 14 centers. Patients were randomized to the TAD or RAD group. Tourniquet time, fluoroscopy time, and complications were compared between the treatment groups. Postoperatively, serial radiographs were obtained every 6 weeks to assess healing, and PROs were obtained at 6 months, 12 months, and 24 months. RESULTS: A total of 91 patients were included, consisting of 51 patients in the TAD and 40 patients in the RAD group, who were similar in age, sex distribution, and 2-year PRO response rate. Tourniquet time and fluoroscopy time were significantly shorter with TAD (mean, 38.1 minutes and 0.85 minutes, respectively) than RAD (mean, 48.2 minutes and 1.34 minutes respectively) (P = .02; P = .004). In the RAD group, chondral injury from K-wire passage into the intra-articular space was reported in 9 of 40 (22%) patients, but no associated postoperative clinical sequelae were identified in these patients. No significant differences between groups were detected in follow-up Pediatric-International Knee Documentation Committee, Lysholm, Marx Activity Scale, or Knee injury and Osteoarthritis Outcome Score Quality of Life scores. Healing parameters were superior at 6 months and 12 months in the TAD group, compared with the RAD group, and secondary OCD surgery occurred in 4% of patients who underwent TAD and 10% of patients who underwent RAD (P = .40). Patients in the TAD group returned to sports earlier than those in the RAD group (P = .049). CONCLUSION: TAD showed shorter operative time and fluoroscopy time and superior healing parameters at 6 and 12 months, but no differences were seen in 24-month healing parameters or PROs at all follow-up time points, when compared with RAD. REGISTRATION: NCT01754298 (ClinicalTrials.gov identifier).

Minimizing Surgeon Radiation Exposure During Operative Treatment of Pediatric Supracondylar Humerus Fractures.

BACKGROUND: Orthopaedic surgeons are exposed to high levels of radiation, which may lead to higher rates of cancer among orthopaedic surgeons. There are a series of techniques currently practiced to pin supracondylar humerus fractures including pinning the arm on the C-arm itself, using a plexiglass rectangle or a graphite floating arm board; however, the variation in radiation exposure to the surgeon is unknown. We aimed to determine how the position of the C-arm affects radiation exposure to the surgeon during the treatment of a pediatric supracondylar humerus fracture. MATERIAL AND METHODS: A simulated operating room was created to simulate a closed reduction and percutaneous pinning of a supracondylar humerus fracture. A phantom model was used to simulate the patient's arm. We assessed performing the procedure with the arm on plexiglass, graphite, or on top of the C-arm image receptor. The C-arm was positioned either with the source down and image receptor up (standard position) or with the source up and image receptor down (inverted position). Radiation exposure was recorded from levels corresponding to the surgeon's head, midline, and groin. The estimated effective dose equivalent was calculated to account for the varying radiation sensitivity of different organs. RESULTS: We found the effective dose equivalent, or the overall body damage from radiation, was 5.4 to 7.8% higher than the surgeon when the C-arm was in the inverted position (source up, image receptor down). We did not find any differences in radiation exposure to the surgeon when the arm was supported on plexiglass versus graphite. CONCLUSION: The C-arm positioned in the standard fashion exposes the surgeon to less damaging radiation. Therefore, when the surgeon is standing, we recommend using the C-arm in the standard position. CLINICAL RELEVANCE: Orthopaedic surgeons who stand should use the C-arm in the standard position to pin supracondylar humerus fractures to lower the risk of ionizing radiation exposure.

Factors Associated With Meniscal and Articular Cartilage Injury in the PLUTO Cohort.

BACKGROUND: Anterior cruciate ligament (ACL) injuries in adults are frequently accompanied by meniscal and articular cartilage damage. However, little is known regarding the association, if any, between physical maturity, hypermobility, or bone bruising and these associated injuries in skeletally immature patients with ACL tears. PURPOSE: To determine if physical maturity, hypermobility, and/or bone bruising is associated with concomitant meniscal and articular cartilage injury in skeletally immature patients with ACL tears. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: At 10 institutions in the United States, consecutive skeletally immature patients with complete ACL tears were enrolled between January 2016 and June 2020. Univariable and multivariable logistic regression analysis was used to assess the effect of variables on the likelihood of articular cartilage and meniscal injury. RESULTS: A total of 748 patients were analyzed. Of these, 85 patients (11.4%) had articular cartilage injuries. These patients had a higher bone age (13.9 vs 13.1 years; P = .001), a higher Tanner stage (P = .009), and increased height (162.9 vs 159.9 cm; P = .03) and were heavier (57.8 vs 54.0 kg; P = .02). For each additional Tanner stage, the odds of articular cartilage injury increased approximately 1.6 times (P < .001). Of the total patients, 423 (56.6%) had meniscal tears. Those with meniscal tears were older (12.6 vs 12.0 years; P < .001), had a higher bone age (13.5 vs 12.8 years; P < .001), had a higher Tanner stage (P = .002), had increased height (162.2 vs 157.6 cm; P < .001), and were heavier (56.6 vs 51.6 kg; P < .001). For each additional Tanner stage, the odds of a meniscal tear increased approximately 1.3 times (P < .001). No association was detected between hypermobility or bone bruising and the likelihood of articular cartilage or meniscal injury. Multivariable regression revealed that increasing Tanner stage was associated with an increasing risk of articular cartilage injury, while weight was associated with an increasing risk of meniscal injury. CONCLUSION: Increasing physical maturity is associated with increased risks of concomitant articular cartilage and meniscal injury in skeletally immature patients with ACL tears. Hypermobility and bone bruising are not associated with articular cartilage or meniscal injury, suggesting that physical maturity, rather than ligamentous laxity, is the primary risk factor for associated injuries in skeletally immature patients with an ACL tear.

MRI hip morphology is abnormal in unilateral DDH and increased lateral limbus thickness is associated with residual DDH at minimum 10-year follow-up.

Purpose: The purpose of the study was to compare the post-reduction magnetic resonance imaging morphology for hips that developed residual acetabular dysplasia, hips without residual dysplasia, and uninvolved contralateral hips in patients with unilateral developmental dysplasia of the hip undergoing closed or open reduction and had a minimum 10-year follow-up. Methods: Retrospective study of patients with unilateral dysplasia of the hip who underwent open/closed hip reduction followed by post-reduction magnetic resonance imaging. Twenty-eight patients with a mean follow-up of 13 ± 3 years were included. In the treated hips, residual dysplasia was defined as subsequent surgery for residual acetabular dysplasia or for Severin grade > 2 at latest follow-up. On post-reduction, magnetic resonance imaging measurements were performed by two readers and compared between the hips with/without residual dysplasia and the contralateral uninvolved side. Magnetic resonance imaging measurements included acetabular version, coronal/ axial femoroacetabular distance, acetabular depth-width ratio, osseous/cartilaginous acetabular indices, and medial/lateral (limbus) cartilage thickness. Results: Fifteen (54%) and 13 (46%) hips were allocated to the "no residual dysplasia" group and to the "residual dysplasia" group, respectively. All eight magnetic resonance imaging parameters differed between hips with residual dysplasia and contralateral uninvolved hips (all p < 0.05). Six of eight parameters differed (all p < 0.05) between hips with and without residual dysplasia. Among these, increased limbus thickness had the largest effect (odds ratio = 12.5; p < 0.001) for increased likelihood of residual dysplasia. Conclusions: We identified acetabular morphology and reduction quality parameters that can be reliably measured on the post-reduction magnetic resonance imaging to facilitate the differentiation between hips that develop with/without residual acetabular dysplasia at 10 years postoperatively. Level of evidence: level III, prognostic case-control study.

Acute Pelvic and Hip Apophyseal Avulsion Fractures in Adolescents: A Summary of 719 Cases.

BACKGROUND: Apophyseal avulsion fractures of the pelvis and hip are common injuries in adolescent athletes. However, high volume comparative studies elucidating the spectrum of injuries are largely absent from the literature. The current study provides a comprehensive analysis of demographic, anatomic, pathophysiological, clinical, and athletic-related variables associated with such injuries in an extensive population of affected adolescents. METHODS: A retrospective review was performed of records of patients presenting to a single tertiary care pediatric hospital between January 1, 2005, and July 31, 2020, collecting variables including patient sex, age, body mass index, fracture location, injury mechanism, sport at the time of injury, and duration of prodromal symptoms. RESULTS: Seven hundred nineteen fractures were identified in 709 patients. The average patient age was 14.6, and 78% of the fractures occurred in male patients. The anterior inferior iliac spine (33.4%), anterior superior iliac spine (30.5%), and ischial tuberosity (19.4%) were the most common fracture sites. The most common injury mechanisms were running (27.8%), kicking (26.7%), and falls (8.8%). The most common sports at the time of injury were soccer (38.1%), football (11.2%), and baseball (10.5%). Fracture site was significantly associated with patient sex, age, body mass index, laterality, mechanism, sport, time from injury, and presence of prodromal symptoms. The annual volume of pelvic avulsion fractures treated at the institution increased significantly from n=17 in 2005 to n=75 in 2019. CONCLUSIONS: Adolescent pelvic and hip avulsion fractures occur during a narrow window of age and skeletal maturation and are frequently sustained during sporting activities. Each fracture location is associated with certain demographic, mechanistic, and patient-specific characteristics. The associations between fracture site and patient-specific or injury-specific variables offer insights into the pathophysiology and possible underlying biomechanical risk factors that contribute to these injuries. LEVEL OF EVIDENCE: This is a level III retrospective study.

Do Adolescent Idiopathic Scoliosis Patients With Vitamin D Deficiency Have Worse Spine Fusion Outcomes?

BACKGROUND: Prior research has shown that patients with adolescent idiopathic scoliosis (AIS) have a higher prevalence of vitamin D deficiency compared with healthy peers. In adult orthopaedic populations, vitamin D deficiency has been shown to be a risk factor for higher reported pain and lower function. We investigated whether there was an association between vitamin D levels and AIS patient-reported outcomes, as measured by the Scoliosis Research Society (SRS-30) questionnaire. METHODS: This was a single-center, cross-sectional study. Postoperative AIS patients were prospectively recruited during routine follow-up visits, 2 to 10 years after spine fusion. Vitamin D levels were measured by serum 25-hydroxyvitamin D (ng/mL). Patients were categorized based on vitamin D level: deficient (<20 ng/mL), insufficient (20 to 29 ng/mL), or sufficient (≥30 ng/mL). The correlation between vitamin D levels and SRS-30 scores was analyzed using multivariable analysis and pair-wise comparisons using Tukey method. RESULTS: Eighty-seven AIS patients (83% female) were enrolled who presented at median 3 years (interquartile range: 2 to 5 y; range: 2 to 10 y) after spine fusion. Age at time of surgery was mean 15 (SD±2) years. Major coronal curves were a mean of 57 (SD±8) degrees preoperatively and 18 (SD±7) degrees postoperatively. It was found that 30 (34%) of patients were vitamin D sufficient, 33 (38%) were insufficient, and 24 (28%) were deficient. Although there was no correlation between vitamin D level and Pain, Mental Health, or Satisfaction domains ( P >0.05), vitamin D-deficient patients were found to be younger ( P <0.001) and had lower SRS-30 function ( P =0.002), Self-image ( P <0.001), and total scores ( P =0.003). CONCLUSIONS: AIS patients with vitamin D deficiency (<20 ng/mL) are more likely to be younger age at time of surgery, and report lower Function, Self-image, and Total SRS-30 scores postoperatively. Further work is needed to determine whether vitamin D supplementation alters curve progression and patient outcomes. LEVEL OF EVIDENCE: Level II-prognostic study.

The Reliability of the AO Spine Upper Cervical Classification System in Children: Results of a Multi-Center Study.

BACKGROUND: There is no uniform classification system for traumatic upper cervical spine injuries in children. This study assesses the reliability and reproducibility of the AO Upper Cervical Spine Classification System (UCCS), which was developed and validated in adults, to children. METHODS: Twenty-six patients under 18 years old with operative and nonoperative upper cervical injuries, defined as from the occipital condyle to the C2-C3 joint, were identified from 2000 to 2018. Inclusion criteria included the availability of computed tomography and magnetic resonance imaging at the time of injury. Patients with significant comorbidities were excluded. Each case was reviewed by a single senior surgeon to determine eligibility. Educational videos, schematics describing the UCCS, and imaging from 26 cases were sent to 9 pediatric orthopaedic surgeons. The surgeons classified each case into 3 categories: A, B, and C. Inter-rater reliability was assessed for the initial reading across all 9 raters by Fleiss's kappa coefficient (kF) along with 95% confidence intervals. One month later, the surgeons repeated the classification, and intra-rater reliability was calculated. All images were de-identified and randomized for each read independently. Intra-rater reproducibility across both reads was assessed using Fleiss's kappa. Interpretations for reliability estimates were based on Landis and Koch (1977): 0 to 0.2, slight; 0.2 to 0.4, fair; 0.4 to 0.6, moderate; 0.6 to 0.8, substantial; and >0.8, almost perfect agreement. RESULTS: Twenty-six cases were read by 9 raters twice. Sub-classification agreement was moderate to substantial with α κ estimates from 0.55 for the first read and 0.70 for the second read. Inter-rater agreement was moderate (kF 0.56 to 0.58) with respect to fracture location and fair (kF 0.24 to 0.3) with respect to primary classification (A, B, and C). Krippendorff's alpha for intra-rater reliability overall sub-classifications ranged from 0.41 to 0.88, with 0.75 overall raters. CONCLUSION: Traumatic upper cervical injuries are rare in the pediatric population. A uniform classification system can be vital to guide diagnosis and treatment. This study is the first to evaluate the use of the UCCS in the pediatric population. While moderate to substantial agreement was found, limitations to applying the UCCS to the pediatric population exist, and thus the UCCS can be considered a starting point for developing a pediatric classification. LEVEL OF EVIDENCE: Level III.

Changes in training patterns and confidence to return to sport in United States collegiate athletes during the COVID-19 pandemic.

OBJECTIVE: To describe the training patterns, return to sport (RTS) confidence, and perceived fitness during the COVID-19 pandemic summer 2020 and to compare training patterns and RTS readiness during COVID-19 versus during the 2019 summer in a cohort of Division III collegiate athletes. METHODS: An electronic survey of varsity athletes ≥18 years at three United States Division III colleges querying athlete demographics, Modified Athletic Identity Scale (mAIMS), changes in training regimen summer 2020 vs. 2019, RTS confidence, and perceived physical fitness. RESULTS: One hundred and ninety-two surveys were completed (19% response). Total reported summer 2020 training decreased by 4 hours/week, with increased aerobic (56% vs. 53%, p = 0.03) and decreased sport-specific training (48% vs 70%, p < 0.001). Median RTS confidence score for formal training and competition was 3 ('neither more or less confident') in men's versus 2 ('less confident') in women's athletes. Median fitness self-assessment for men's athletes was 3 ('neither more nor less physically fit') compared to previous season versus median score of 2 ('less physically fit) among women's athletes (p = 0.004). For each mAIMS unit, training increased by 11 minutes/week (95% CI: 2-19 minutes; p = 0.01) and sport-specific training increased by 1.3% (95% CI: 0.5-2.2%; p = 0.003), controlling for age, sport, grade, and school. mAIMS was not associated with confidence or fitness rating. CONCLUSION: Collegiate athletes decreased overall training hours, particularly sport-specific training time during the COVID-19 summer compared to the prior summer. Athletic identity was related to overall and sport-specific training hours but not confidence to RTS or fitness.

Reliability of the Masada Classification for Forearm Involvement in Patients With Hereditary Multiple Osteochondromas (HMO).

BACKGROUND: Classifications describing forearm lesions in patients with Hereditary Multiple Osteochondromatosis (HMO) have been used to recommend surgical intervention and stratify outcomes; however, there is no consensus on which classification offers greater reliability. The purpose of this study was to determine the reliability of the Masada classification and newer classifications among pediatric hand surgeons. METHODS: One hundred one patients with HMO between June 2014 and October 2019 were enrolled in the Congenital Upper Limb Differences (CoULD) Registry. Of those, 67 patients with 101 forearms were included. Four pediatric hand surgeons from the CoULD study group undertook an online evaluation. Each rater classified radiographs according to the Masada classification. Six weeks later, raters were asked to reclassify images according to the Masada, Gottschalk, and Jo classifications. Rater agreement for these classifications was assessed by estimating Fleiss kappa along with a 95% CI. RESULTS: Interrater agreement for Masada classification after the first reading was poor (κ=0.35; 95% CI=0.30-0.41) across all raters. Interrater agreement across the 4 raters decreased for the Masada classification from the first to the second reading (κ=0.35 vs 0.21; P <0.001). Intrarater agreement for the Masada classification ranged from 0.32 to 0.63 from the first to the second study reading. Gottschalk and Jo classifications yielded significantly better interrater agreement compared with Masada (κ=0.43 vs 0.21; P <0.001). Unclassifiable cases were highest in the Masada classification (34% to 44%) and lower in the Jo (17%) and Gottschalk (14%) classifications. CONCLUSION: Despite wide use, the Masada classification was found to have low reliability when classifying forearm deformities in HMO. Gottschalk offered more options for location, yet lacked deformity description including radial head dislocation. Jo classification offered more locations than Masada and incorporated radial head dislocation in some patterns. Based on the shortcomings in all 3 classification systems, the development of a more inclusive and reliable classification is warranted. LEVEL OF EVIDENCE: Level II; Diagnostic.

Blood Pressure Responses During Exercise: Physiological Correlates and Clinical Implications.

BACKGROUND: Abnormal blood pressure (BP) responses to exercise can predict adverse cardiovascular outcomes, but their optimal measurement and definitions are poorly understood. We combined frequently sampled BP during cardiopulmonary exercise testing with vascular stiffness assessment to parse cardiac and vascular components of exercise BP. METHODS: Cardiopulmonary exercise testing with BP measured every two minutes and resting vascular tonometry were performed in 2858 Framingham Heart Study participants. Linear regression was used to analyze sex-specific exercise BP patterns as a function of arterial stiffness (carotid-femoral pulse wave velocity) and cardiac-peripheral performance (defined by peak O2 pulse). RESULTS: Our sample was balanced by sex (52% women) with mean age 54±9 years and 47% with hypertension. We observed variability in carotid-femoral pulse wave velocity and peak O2 pulse across individuals with clinically defined exercise hypertension (peak systolic BP [SBP] in men ≥210 mm Hg; in women ≥190 mm Hg). Despite similar resting SBP and cardiometabolic profiles, individuals with higher peak O2 pulse displayed higher peak SBP (P≤0.017) alongside higher fitness levels (P<0.001), suggesting that high peak exercise SBP in the context of high peak O2 pulse may in fact be favorable. Although both higher (favorable) O2 pulse and higher (adverse) arterial stiffness were associated with greater peak SBP (P<0.0001 for both), the magnitude of association of carotid-femoral pulse wave velocity with peak SBP was higher in women (sex-carotid-femoral pulse wave velocity interaction P<0.0001). In sex-specific models, exercise SBP measures accounting for workload (eg, SBP during unloaded exercise, SBP at 75 watts, and SBP/workload slope) were directly associated with the adverse features of greater arterial stiffness and lower peak O2 pulse. CONCLUSIONS: Higher peak exercise SBP reflects a complex trade-off between arterial stiffness and cardiac-peripheral performance that differs by sex. Studies of BP responses to exercise accounting for vascular and cardiac physiology may illuminate mechanisms of hypertension and clarify clinical interpretation of exercise BP.

Prevalence of perinatal factors in infants with brachial plexus birth injuries and their association with injury severity.

OBJECTIVES: To determine the prevalence of perinatal factors associated with brachial plexus birth injury (BPBI) in affected infants and their relationship with BPBI severity. STUDY DESIGN: Retrospective study of BPBI infants prospectively enrolled in a multicenter registry. The prevalence of perinatal factors was calculated. Infants were stratified by injury severity and groups were compared to determine the association of severity and perinatal factors. RESULTS: Seven-hundred-ninety-six BPBI infants had a mean 4.2 ± 1.6 perinatal factors. Nearly all (795/796) reported at least one factor, including shoulder dystocia(96%), no clavicle fracture (91%), difficult delivery(84%), parity >1(61%) and birthweight >4000 g(55%). Ten-percent (74/778) had Horner's syndrome and 28%(222/796) underwent nerve surgery. Birth asphyxia and NICU admission were significantly associated with injury severity. CONCLUSIONS: NICU admission and asphyxia were associated with BPBI severity. An improved understanding of the relationship between perinatal factors and BPBI severity may be used to guide early referral to BPBI providers and support prevention efforts.

Lyme Arthritis in the Pediatric Knee: Clinical and Magnetic Resonance Imaging Differentiators.

Lyme disease is the most prevalent tick-borne illness in the United States, especially endemic in the Northeast and Upper Midwest. Distinguishing Lyme arthritis (LA), the most common manifestation of the disease in children, from septic arthritis (SA) can be challenging because of overlap in clinical presentations. This study examined the role of magnetic resonance imaging (MRI) as an adjunct to clinical and laboratory features used to differentiate between LA and SA in children and adolescents. Methods: The medical records and MRI scans of children who presented between 2009 and 2019 with an acute knee effusion ultimately diagnosed as LA or SA were retrospectively reviewed. Data collection included clinical information on the modified Kocher criteria (weight-bearing, fever, blood serology including white blood-cell [WBC] count, C-reactive protein [CRP], and erythrocyte sedimentation rate [ESR]), MRI findings, and serology confirmation of LA or bacterial SA. A total of 87 cases of confirmed LA and 9 cases of SA were identified. Results: The 2 cohorts had substantial clinical overlap with regard to the ability to bear weight, fever, and joint aspirate WBC count. Differences between the 2 groups in several MRI characteristics, specifically vastus lateralis myositis, subcutaneous edema, and lymphadenopathy, were significant. A multivariate analysis demonstrated that weight-bearing, CRP of <3 mg/L, absence of subcutaneous edema, myositis of multiple muscles including the vastus lateralis, and lymphadenopathy were predictive of LA. Conclusions: LA should be strongly suspected in endemic areas of the United States when children present with a knee effusion. The addition of MRI criteria to clinical and laboratory findings significantly improved the predictive value for identifying LA. Level of Evidence: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.