The Creation and Validation of an Ankle Bone Age Atlas and Data Predicting Remaining Ankle Growth.

BACKGROUND: The purpose of the current study was 2-fold: (1) to create and validate an ankle bone age atlas spanning the pediatric and adolescent years and (2) to utilize this atlas in conjunction with distal tibia/fibular growth data as measured on serial radiographs to develop a predictive growth model for the lower extremity. METHODS: Radiographs were surveyed to identify distinguishable, reproducible, radiographic features. Radiographic features of the tibia, fibula, hindfoot, and midfoot from 270 patients were identified and a "standard" for each age/sex was selected to create an atlas. A separate cohort of 90 ankle radiographs was selected to validate the atlas. A subcohort of 41 patients with left-hand radiographs within 3 months of ankle imaging was used to compare the 2 bone age approaches. Harris growth lines were evaluated in 304 serial images of the distal tibia to determine the remaining growth. RESULTS: The distal tib/fib ossification centers provided the best age assessment for early childhood (male age: 1 to 8 y; female age: 1 to 4 y). The ossification/fusion of the calcaneal apophysis provided the best age assessment in the preadolescent stage (male age: 6 to 14 y; female age: 5 to 12 y). The closure of the distal tib/fib physes best determined skeletal maturity (male age: 14 to 16 y; female age: 12 to 14 y). The ankle atlas had excellent interobserver and intraobserver reliability (intraclass correlation coefficient=0.993, P <0.001 and 0.998, P <0.001), respectively. We found an excellent correlation between the patient's chronologic age and ankle bone age ( r =0.984; P <0.001). Ankle bone age assessment and Greulich and Pyle were correlated ( rs =0.822, P <0.001). We found that males with a bone age of ≥15 years and females with a bone age of ≥13 years had ≤2 mm of residual growth of the distal tibia/fibula physes. CONCLUSIONS: bone age can be determined using ankle films ordered to assess/treat ankle injuries. This tool, along with our growth remaining table, may have important clinical implications when managing patients with ankle trauma with premature physeal closure. LEVEL OF EVIDENCE: IV.

What Happens to Youth Baseball Players Diagnosed With Little League Shoulder and Little League Elbow Syndrome?

BACKGROUND: The long-term prognosis of baseball and softball players diagnosed with Little League elbow (LLE) and Little League shoulder (LLS) is unknown. Many of these athletes are potentially at risk of developing future shoulder and elbow injuries that may require surgical intervention. This study's purpose is to retrospectively assess 5-year patient-reported outcomes and career progression of a series of youth baseball and softball players diagnosed with LLE and LLS. METHODS: This institutional review board-approved, single-center, retrospective study evaluated 5-year outcomes of a cohort of youth baseball and softball players diagnosed with LLE and LLS between 2013 and 2017. Demographic and clinical data was recorded including age, gender, primary position, and months played per year. A standardized phone survey was obtained approximately 5 years post-treatment to assess upper extremity function, career progression, and pain recurrence. RESULTS: Sixty-one patients (44 LLE, 17 LLS) met the inclusion criteria and participated in a standardized phone survey. The mean age at the time of diagnosis was 13.2 years and all but one of the athletes were male. On average, about 80% (34/44 LLE, 15/17 LLS) played baseball 9 months or more per year. After diagnosis and nonoperative management, more than 80% (37/44 LLE, 14/17 LLS) were able to return to competition, but up to 40% of players changed positions (9/44 LLE, 7/17 LLS). Five years later, less than half (21/44 LLE, 8/17 LLS) were playing baseball actively. The recurrence rate was >20% (9/42 LLE, 6/17 LLS) with a mean time of recurrence of 8.8 months. Patients who experienced symptom recurrence were less likely to play baseball 5 years later and had lower patient-reported outcomes. CONCLUSIONS: A diagnosis of LLE and LLS in early adolescence can be a setback for a young athlete. Fortunately, most athletes will be able to return to competition with ∼50% still competing at 5 years. Very few will progress to future arm surgery, but recurrence rates are relatively high, and these athletes are less likely to participate in their sport 5 years later. LEVEL OF EVIDENCE: Level IV-Retrospective cohort study.

Changes in Fracture Shortening Occur in the First 2 Weeks Following Completely Displaced Adolescent Clavicle Fractures.

BACKGROUND: Shortening of midshaft clavicle fractures has been described as a critical fracture characteristic to guide treatment. The degree to which shortening may change in the initial weeks following injury has not been well studied. The purpose of this study was to evaluate the change in shortening of adolescent clavicle fractures in the first 2 weeks following injury. METHODS: This was a multicenter study of prospectively collected data, which was acquired as a part of a cohort study of adolescent clavicle fractures. A consecutive series of patients 10 to 18 years of age with completely displaced diaphyseal clavicle fractures with baseline radiographs 0 to 6 days from the date of injury, as well as 7 to 21 days from the date of injury, were included. Measurements of end-to-end (EES) and cortex-to-corresponding-cortex (CCS) shortening were performed. RESULTS: A total of 142 patients were included. Baseline radiographs were obtained at a mean of 1.0 day following injury with mean EES of 22.3 mm, and 69% of patients demonstrating >20 mm of shortening. Follow-up radiographs obtained at a mean of 13.8 days postinjury demonstrated a mean absolute change in EES of 5.4 mm. Forty-one percentage of patients had >5 mm of change in EES. When analyzing changes in shortening relative to the specific threshold of 20 mm, 18 patients (41%) with <20 mm EES increased to ≥20 mm EES, and 19 patients (19%) with ≥20 mm EES decreased to <20 mm EES at 2-week follow-up. CONCLUSIONS: Clinically significant changes in fracture shortening occurred in 41% of adolescents with completely displaced clavicle fractures in the first 2 weeks after injury. In 26% of patients, this resulted in a change from above or below the commonly used shortening threshold of 20 mm, potentially altering the treatment plan by many providers. There is no evidence to suggest that adolescent clavicle fracture shortening affects outcomes, and as such, the authors do not advocate for the use of this parameter to guide treatment. However, among physicians who continue to use this parameter to guide treatment, this study supports that repeat radiographic assessment 2 weeks postinjury may be a better measure of the true shortening of this common adolescent injury. LEVEL OF EVIDENCE: Level IV-case series.

Subsequent Forearm Fractures Following Initial Surgical Fixation.

INTRODUCTION: Forearm fractures are a common pediatric injury. Currently, there is no consensus on treatment for fractures that recur following initial surgical fixation. The objective of this study was to investigate the subsequent fracture rate and patterns and describe the treatment of these forearm fractures. METHODS: We retrospectively identified patients who underwent surgical treatment for an initial forearm fracture at our institution between 2011 and 2019. Patients were included if they sustained a diaphyseal or metadiaphyseal forearm fracture that was initially treated surgically with a plate and screw construct (plate) or elastic stable intramedullary nail (ESIN), and if they subsequently sustained another fracture that was treated at our institution. RESULTS: A total of 349 forearm fractures were treated surgically with ESIN or a plate fixation. Of these, 24 sustained another fracture, yielding a subsequent fracture rate of 10.9% for the plate cohort and 5.1% for the ESIN cohort ( P =0.056). The majority of plate refractures (90%) occurred at the proximal or distal plate edge, while 79% of the fractures treated previously with ESINs occurred at the initial fracture site ( P <0.001). Ninety percent of plate refractures required revision surgery, with 50% underwent plate removal and conversion to ESIN, and 40% underwent revision plating. Within the ESIN cohort, 64% were treated nonsurgically, 21% underwent revision ESINs, and 14% underwent revision plating. Tourniquet time for revision surgeries were shorter for the ESIN cohort (46 vs. 92 min; P =0.012). In both cohorts, all revision surgeries had no complications and healed with evidence of radiographic union. However, 9 patients (37.5%) underwent implant removal (3 plates and 6 ESINs) after subsequent fracture healing. CONCLUSIONS: This is the first study to characterize subsequent forearm fractures following both ESIN and plate fixation and to describe and compare treatment options. Consistent with the literature, refractures following surgical fixation of pediatric forearm fractures may occur at a rate ranging from 5% to 11%. ESINs are both less invasive at the time of initial surgery and can often be treated nonoperatively if there is a subsequent fracture, while plate refractures are more likely to be treated with a second surgery and have a longer average surgery time. LEVEL OF EVIDENCE: Level IV-retrospective case series.

Intermediate-term Outcomes in Adolescent Recurrent Ankle Instability Managed With a Modified Broström-Gould Procedure Augmented With Distal Fibular Periosteum Incorporation.

BACKGROUND: Once a child has developed chronic ankle instability with recurrent events despite conservative treatment, then ligamentous repair is warranted. We utilize a modification of the modified Broström-Gould technique that further incorporates the distal fibular periosteum into the construct. The purpose of this study was to describe the intermediate-term outcomes of our modified Broström-Gould technique for chronic lateral ankle instability in childhood athletes. METHODS: A retrospective review of children who underwent the surgical technique over a 10-year time period (2010 to 2019) was performed, excluding those with <2 years of follow-up. Demographic, surgical, and clinical data were recorded, as well as outcome scores: (1) the Marx activity scale, (2) University of California, Los Angeles activity score, and (3) foot and ankle outcomes score. Recurrent instability events, repeat surgeries, satisfaction with the surgical experience, and return to sport (if applicable) were also recorded. RESULTS: Forty-six children (43 females) with 1 bilateral ankle met the criteria with a mean age at surgery of 14.8 years, and a mean follow-up duration of 4.9 years. The mean Marx activity score was 9.0±5.1, the mean University of California, Los Angeles score was 8.3±1.8, and the mean total foot and ankle outcomes score was 84.0±15.6. Twenty-six ankles (55.3%) reported having at least 1 recurrent episode of instability and 6 of the ankles (12.8%) underwent revision surgery between 3.5 months and 6.5 years of the index procedure. Thirty-nine (84.8%) patients responded that they would undergo our surgery again. CONCLUSION: A modified Broström-Gould procedure can be performed in children with the incorporation of the adjacent periosteum, but recurrence of instability is distinctly possible with longer follow-up with a risk for revision surgery despite good subjective outcomes. LEVEL OF EVIDENCE: Level IV; retrospective case series.

Allograft Anterior Cruciate Ligament Reconstruction in Adolescent Patients May Result in Acceptable Graft Failure Rate in Nonpivoting Sports Athletes.

BACKGROUND: Studies have demonstrated that pediatric patients have an increased risk of failure with allograft anterior cruciate ligament reconstruction (ACLR); however, there is no study investigating whether allograft ACLR may be safe in older adolescent patients who are not returning to competitive pivoting sports (ie, low risk). The purpose of this study was to assess outcomes for low-risk older adolescents selected for allograft ACLR. METHODS: We performed a retrospective chart review of patients younger than 18 years who received a bone-patellar-tendon-bone allograft or autograft ACLR by a single orthopaedic surgeon from 2012 to 2020. Patients were offered allograft ACLR if they did not intend to return to pivoting sports for 1 year. The autograft cohort was matched 1:1 based on age, sex, and follow-up. Patients were excluded for skeletal immaturity, multiligamentous injury, prior ipsilateral ACLR, or concomitant realignment procedure. Patients were contacted to obtain patient-reported outcomes at ≥2 years follow-up, including single assessment numerical evaluation, surgery satisfaction, pain scores, Tegner Activity Scale, and the Lysholm Knee Scoring Scale. Parametric and nonparametric tests were used as appropriate. RESULTS: Of the 68 allografts, 40 (59%) met inclusion and 28 (70%) were contacted. Among the 456 autografts, 40 (8.7%) were matched and 26 (65%) were contacted. Two allograft patients (2/40; 5%) failed at a median (interquartile range) follow-up of 36 (12, 60) months. There were 0/40 failures in the autograft cohort and 13/456 (2.9%) among the overall autografts; neither were significantly different from the allograft failure rate (both P > 0.05). Two (5.0%) patients in the autograft cohort required manipulation under anesthesia and arthroscopic lysis of adhesions. There were no significant differences between cohorts for single assessment numerical evaluation, Lysholm, Tegner, pain, and satisfaction scores (all P > 0.05). CONCLUSIONS: Although ACL allograft failure rates remain nearly two times higher than autograft failure rates in older adolescents, our study suggests that careful patient selection can potentially bring this failure rate down to an acceptable level. LEVEL OF EVIDENCE: Level III; retrospective matched cohort study.

Management of Pediatric and Adolescent Sublime Tubercle Injuries: Isolated and Complex Patterns Demonstrate Distinct Etiologies and Radiographic Outcomes.

BACKGROUND: The aim of this study was to assess the patient demographics, epidemiology, mechanism of injury, and natural history of sublime tubercle avulsion injuries. METHODS: A multicenter retrospective study was performed in which sublime tubercle avulsion injuries were identified by surgeon records and database query of radiology reports. Demographic data and imaging were reviewed for each case, and injuries were classified as type 1 (isolated injuries with a simple bony avulsion or periosteal stripping) or type 2 (complex injuries with an associated elbow fracture or dislocation). Treatment modality and evidence of radiographic healing at a minimum of 3 months were collected. RESULTS: Forty patients (78% male) with a median age of 15 years (range, 8 to 19 years) were identified with sublime tubercle avulsion injuries. Sixty-eight percent of cases (n=27) were determined to be type 1 injuries, and 32% (n=13) were classified as type 2 injuries. The majority of type 1 injuries (59%) occurred via a noncontact mechanism in overhead-throwing athletes, whereas 100% of the type 2 injuries were sustained via a contact mechanism. Type 1 injuries presented in a delayed manner in 19% of cases, whereas no type 2 injuries (0%) were delayed in presentation. Type 1 injuries infrequently underwent surgical intervention (19%), whereas 54% of type 2 injuries required surgery. Of those that did not undergo initial surgical management at a minimum of 3-month radiographic follow-up, 9/11 (82%) of type 1 injuries and 0/4 (0%) of type 2 injuries demonstrated evidence of healing. Only 1 case required reoperation (type 2 injury). CONCLUSIONS: This series of adolescents with sublime tubercle avulsion injuries expands our understanding of the epidemiology of this rare injury, which was previously only described as a noncontact injury in baseball players. Type 1 injuries are more likely to occur via a noncontact mechanism and generally demonstrate radiographic evidence of healing after a period of rigid immobilization. Conversely, type 2 injuries are more likely to undergo initial surgical intervention, and those managed nonoperatively are less likely to achieve radiographic healing. Further studies are needed to elucidate treatment protocols and long-term functional outcomes. LEVEL OF EVIDENCE: Level IV-case series.

Variability in Pain Management Practices for Pediatric Anterior Cruciate Ligament Reconstruction.

BACKGROUND: The opioid epidemic in the United States is a public health crisis. Pediatric orthopaedic surgeons must balance adequate pain management with minimizing the risk of opioid misuse or dependence. There is limited data available to guide pain management for anterior cruciate ligament reconstruction (ACLR) in the pediatric population. The purpose of this study was to survey current pain management practices for ACLR among pediatric orthopaedic surgeons. METHODS: A cross-sectional survey study was conducted, in which orthopaedic surgeons were asked about their pain management practices for pediatric ACLR. The voluntary survey was sent to members of the Pediatric Orthopaedic Society of North America. Inclusion criteria required that the surgeon perform anterior cruciate ligament repair or reconstruction on patients under age 18. Responses were anonymous and consisted of surgeon demographics, training, practice, and pain management strategies. Survey data were assessed using descriptive statistics. RESULTS: Of 64 included responses, the average age of the survey respondent was 48.9 years, 84.4% were males, and 31.3% practiced in the southern region of the United States. Preoperative analgesia was utilized by 39.1%, 90.6% utilized perioperative blocks, and 89.1% prescribed opioid medication postoperatively. For scheduled non-narcotic medications postoperatively 82.8% routinely advocated and 93.8% recommended cryotherapy postoperatively.Acetaminophen was the most used preoperative medication (31.3%), the most common perioperative block was an adductor canal block (81.0%), and the most common postoperative analgesic medication was ibuprofen (60.9%). Prior training or experience was more frequently reported than published research as a primary factor influencing pain management protocols. CONCLUSIONS: Substantial variability exists in pain management practices in pediatric ACLR. There is a need for more evidence-based practice guidelines regarding pain management. LEVEL OF EVIDENCE: Level V.

Nonoperative Versus Operative Treatment of Type IIA Supracondylar Humerus Fractures: A Prospective Evaluation of 99 Patients.

BACKGROUND: Although current clinical practice guidelines from the American Academy of Orthopaedic Surgeons suggest that Type II and III supracondylar humerus (SCH) fractures be treated by closed reduction and pin fixation, controversy remains as to whether type IIa fractures with no rotation or angular deformity require surgery. The purpose of our study was to prospectively compare radiographic and functional outcomes of type IIa SCH fractures treated with or without surgery. METHODS: Between 2017 and 2019, 105 patients between 2 and 12 years of age presenting with type IIa SCH fractures and without prior elbow trauma, neuromuscular or metabolic conditions, were prospectively enrolled. Ten orthopaedic surgeons managed the patients with 5 preferring surgical treatment and 5 preferring an initial attempt at nonoperative treatment. Patients in the nonoperative cohort were managed with a long-arm cast and close radiographic follow-up. Patients underwent a standardized protocol, including 3 to 4 weeks of casting, bilateral radiographic follow-up 6 months postinjury, and telephone follow-up at 6, 12, and 24 months. RESULTS: Ninety-nine patients met the inclusion criteria (45 nonoperative and 54 operatives). Of the nonoperative patients, 4 (9%) were converted to surgery up to their first clinical follow-up. No differences were identified between the cohorts with respect to demographic data, but patients undergoing surgery had on average 6 degrees more posterior angulation at the fracture site preoperatively (P<0.05). At the final clinical follow-up (mean=6 mo), the nonoperative group had more radiographic extension (176.9 vs 174.4 degrees, P=0.04) as measured by the hourglass angle, but no other clinical or radiographic differences were appreciated. Complications were similar between the nonoperative and operative groups: refracture (4.4 vs 5.6%), avascular necrosis (2.2 vs 1.9%) and infection (0 vs 1.9%) (P>0.05). Patient-reported outcomes at a mean of 24 months showed no differences between groups. CONCLUSION: Contrary to American Academy of Orthopaedic Surgeons guidelines, about 90% of patients with type IIa supracondylar fractures can be treated nonoperatively and will achieve good radiographic and functional outcomes with mild residual deformity improving over time. Patients treated nonoperatively must be monitored closely to assess for early loss of reduction and the need for surgical intervention.

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.

Elastic Intramedullary Nails in the Treatment of Pediatric Length Unstable Femur Fractures.

BACKGROUND: Elastic intramedullary nails (EINs) are the treatment of choice for school-age children (5 to 12) with diaphyseal femur fractures. Previous literature suggests that EINs are an effective treatment for stable fracture patterns, but may be inadequate for unstable fracture patterns. The purpose of this study was to evaluate whether patients with length unstable fractures had a higher complication rate than those with length stable fractures when treated with EINs. METHODS: All patients with diaphyseal femur fractures treated with EINs over a 22-year period at a single institution were reviewed. Patients were excluded if they had a pathologic fracture, neuromuscular disorder, spinal cord injury with subsequent involvement of affected limb, metabolic bone disease, or if they did not have at least 6-month follow-up. RESULTS: A total of 85 patients with 87 diaphyseal femur fractures treated with EINs were included in the study. In all, 57.5% of the fractures were categorized as length stable and 42.5% were length unstable. Fourteen percent of length stable patients had a residual angular deformity compared with 5.4% of the length unstable group (P=0.24). The length unstable group experienced more shortening at the fracture site than the patients in the length stable group (P=0.003), but no patient required further intervention for their shortening. Two patients in the length stable group experienced overgrowth >2 cm and required subsequent surgery. No relationship was observed between fracture pattern and frequency of complications (length stable 8% vs. length unstable 10.8%, P=0.69). Finally, the knee immobilizer group (10.7%) and the long leg cast group (18.2%) had significantly higher complication rates than the single leg spica cast group (0%, P<0.05). CONCLUSIONS: There was no significant difference in complication rate between length stable and unstable fractures treated with EINs. Adjunctive spica casting may be protective against postoperative complications. While fracture shortening was more likely in the length unstable group, it did not result in increased rate of limb length discrepancy at final follow-up. LEVEL OF EVIDENCE: Level IV, Case Series.

Does Youth Baseball Result in Morphologic Changes of the Lateral Elbow? A Prospective MRI Study.

BACKGROUND: Stress from overhead throwing results in morphologic changes to the shoulder in youth baseball players. With greater valgus torque stresses, the elbow experiences injuries specifically attributed to throwing. However, no previous work that we know of has assessed throwing-related morphologic changes of the elbow without associated conditions. QUESTIONS/PURPOSES: (1) Do children who play competitive baseball have enlargement or overgrowth of their radial head shape and/or capitellum compared with the nondominant elbow on MRI? (2) Do children who stop playing year-round baseball have less enlargement of the lateral elbow structures than children who maintain a high level of play? METHODS: A prospective study was conducted between 2015 and 2018 on preadolescent boys who underwent voluntary MRI of their bilateral elbows before the start of the spring baseball season. Twenty-six children agreed to participate out of a four-team league that was asked to participate; their first MRI was obtained at a mean (range) age of 12 years (10 to 13). We also obtained their history related to throwing and performed a physical examination. Players had a mean of 5.6 years of playing before their first MRI, and half the children (13 of 26) were year-round baseball players. Sixty-two percent (16 of 26) reported being either or both a pitcher or catcher as their primary position. No child was excluded from participation. Three years later, these boys were asked to return for repeat MRI and physical examinations. Fifty-eight percent (15 of 26) of players were still playing at the 3-year MRI. Continued play or new onset of pain was documented. Radiographic measurements were then compared between dominant and nondominant arms, and the differences of these changes were compared between those who had continued playing during the study period and those who had quit. The measurements were made in all three planes of the radial head and capitellum, both osseous and cartilaginous. Measurement intrarater and interrater reliability were in the good-to-excellent range (intraclass correlation coefficient 0.77 to 0.98). RESULTS: When we compared dominant and nondominant arms, we found there was no dominant arm overgrowth (difference between baseline and 3-year measurements) in any measurement; for example, sagittal capitellum measurements in dominant arms were 2.5 ± 1.1 mm versus non-dominant arms: 2.8 ± 1.1 mm (mean difference -0.23 [95% CI -0.55 to 0.08]; p = 0.13). There was only undergrowth of the cartilaginous axial diameter of the radial head (change in dominant: 2.5 ± 1.3 mm; change in nondominant: 3.2 ± 1.7 mm; mean difference -0.64 mm [95% CI -1.2 to -0.06]; p = 0.03). There was no enlargement of the lateral elbow structures when children who continued to play were compared with children who stopped playing; for example, the difference in the bone-only growth ratio of the sagittal radial head to humerus of those still playing was 0.001 ± 0.03 and it was 0.01 ± 0.03 for those not playing (mean difference -0.01 [95% CI -0.04 to 0.01]; p = 0.29). CONCLUSION: In healthy children who play baseball for multiple years between the ages of 6 to 11 years, continued torque at the elbow from throwing does not result in morphologic changes as it does in the shoulder. Despite evidence that injuries and surgery because of long-term participation in a throwing sport results in a larger radial head and capitellum, our study presents evidence that outside an injured elbow, throwing alone does not appear to change the morphology of the lateral elbow. Therefore, changes to the radial head size could presuppose other elbow pathology and future study could be performed to better evaluate the correlation. LEVEL OF EVIDENCE: Level I, prognostic study.

Glenoid Pathology, Skeletal Immaturity, and Multiple Preoperative Instability Events Are Risk Factors for Recurrent Anterior Shoulder Instability After Arthroscopic Stabilization in Adolescent Athletes.

PURPOSE: To identify risk factors for recurrent shoulder instability after arthroscopic stabilization in adolescent athletes. METHODS: A retrospective case-control study was undertaken of all patients younger than 18 years undergoing arthroscopic shoulder stabilization for anterior instability between 2009 and 2016. Two patient cohorts were identified: (1) patients with recurrent instability (frank dislocations or subluxations) after arthroscopic stabilization and (2) an age- and sex-matched cohort of patients with no recurrent instability at a minimum of 2 years' follow-up from index surgery. Patient demographic, injury, radiographic, and surgical variables were recorded. Variables with P < .10 on univariate analysis were entered into a binary logistic multivariate regression analysis. RESULTS: We identified 35 patients (20.5%) in whom arthroscopic stabilization failed at a mean of 1.2 ± 1.0 years after their index surgical procedure. A separate age- and sex-matched cohort of 35 patients with no evidence of recurrent instability was identified (mean follow-up, 5.4 ± 2.0 years; minimum follow-up, 2 years). Univariate analysis identified increased glenoid bone loss (P = .039), decreased glenoid retroversion (P = .024), and more than 1 instability event prior to surgery (P = .017) as significant risk factors for recurrent instability. Multivariate regression analysis revealed that glenoid retroversion less than 6°, skeletal immaturity, and more than 1 prior instability event significantly and independently predicted future recurrence. The risk of recurrence after arthroscopic stabilization was increased by 3 times in patients with 2 risk factors and by 4 times in patients with all 3 risk factors. CONCLUSIONS: Anterior glenoid bone loss, glenoid version, skeletal immaturity, and multiple preoperative instability events are risk factors for failed arthroscopic stabilization in adolescent athletes with anterior instability. LEVEL OF EVIDENCE: Level III, case-control study.

Changes in superior displacement, angulation, and shortening in the early phase of healing for completely displaced midshaft clavicle fractures in adolescents: results from a prospective, multicenter study.

BACKGROUND: Progressive displacement of diaphyseal clavicle fractures has been observed in adult patients, at times necessitating a change from nonoperative to operative treatment. Whether this occurs in adolescent patients has not been well investigated. The purpose of this study was to assess the rate and extent of progressive clavicle fracture displacement in adolescent patients following injury and during the early stages of healing. METHODS: This was a multicenter study evaluating prospective data that had previously been collected as part of a larger study evaluating the functional outcomes of adolescent clavicle fractures. A consecutive series of completely displaced diaphyseal clavicle fractures in patients aged 10-18 years treated at 1 of 3 tertiary-care pediatric trauma centers was included; all fractures underwent standardized imaging within 2 weeks of the date of injury and during the course of healing (5-20 weeks after injury). Measurements of clavicle shortening, superior displacement, and angulation were performed using validated techniques. Progressive displacement and/or interval improvement in fracture alignment, as well as the subsequent need for surgical intervention, was noted. Patient demographic and radiographic parameters were assessed as possible risk factors for interval displacement. RESULTS: One hundred patients met the inclusion criteria. Mean end-to-end shortening, cortex-to-cortex shortening, superior displacement, and angulation at the time of injury were 24 mm, 15 mm, 15 mm, and 7°, respectively. At a mean of 10 weeks after injury, the fracture alignment improved across all 4 measurements for the overall cohort, with mean improvements of 3.5 mm in end-to-end shortening, 3.3 mm in cortex-to-cortex shortening, 2.1 mm in superior displacement, and 2° in angulation. By use of a clinical threshold of a change in shortening or displacement of 10 mm or change in angulation of 10°, 26% of fractures improved, 4% worsened, and 70% remain unchanged. Patients with more severe fractures were more likely to have improved alignment than were patients with less displaced fractures (P < .001). No patient underwent surgical intervention for progressive displacement. CONCLUSION: Significant early improvements in fracture alignment were observed in a substantial percentage of adolescent patients with completely displaced clavicle fractures. Among the most severely displaced fractures, shortening improved approximately 6 mm and angulation improved approximately 9°. In 4% of cases, increased displacement was observed, but this tended to be mild, and in no cases did it prompt surgical intervention. This finding indicates that the true final deformity after an adolescent clavicle fracture is commonly less than that present at the time of injury.

Suture-button Versus Screw Fixation in Adolescent Syndesmotic Injuries: Functional Outcomes and Maintenance of Reduction.

BACKGROUND: Fixation of the tibiofibular syndesmosis is often performed with a trans-syndesmotic screw (SS) or suture-button (SB). SB fixation has been shown to have lower rates of postoperative syndesmotic malreduction, late diastasis, and implant removal, though some studies have found complications related to infection and implant subsidence. The purpose of this study was to compare maintenance of reduction, complications, implant removal and functional outcomes of SB versus SS fixation in adolescents. METHODS: A retrospective chart review identified patients who underwent syndesmotic fixation from 2010 to 2019 at a single institution. Loss of syndesmotic reduction (diastasis) was defined as either a >2 mm increase in tibiofibular clear space or >2 mm decrease in tibiofibular overlap, and corresponding incongruence of the ankle mortise (medial clear space 1 millimeter greater than superior clear space). Functional outcomes were collected at a minimum of 1 year postsurgery using the Foot and Ankle Ability Measure (FAAM). RESULTS: Seventy-seven adolescents (45 SS, 32 SB) were included (mean age: 16±1.5 y). Forty-five patients had Weber C fibula fractures, 27 Weber B fractures, and 5 had isolated syndesmotic injuries or small posterior malleolus fractures. Fifty-one patients (66%) had functional outcomes available. There was no significant difference in mean FAAM Sports score between the 2 groups (SB=94.8%, SS=89.8%) at mean follow-up of 4.0±2.1 years. Syndesmotic implant removal occurred in 36/45 patients (80%) in the SS group compared with 4/32 patients (13%) in the SB group. There was 1 case of syndesmotic malreduction requiring revision surgery in the SS group, and no cases of postoperative malreduction or diastasis in the SB group. Nine patients in the SB group and 8 in the SS group weighed over 100 kilograms, with no cases of diastasis in these larger patients. There were 4 superficial infections and 1 deep infection in the screw group, with 1 superficial infection in the SB group. CONCLUSIONS: While both SB and screw fixation maintained syndesmotic reduction, SB fixation led to lower rates of implant removal surgery. SB fixation was equally effective at preventing recurrent diastasis in adolescents weighing over 100 kilograms, and functional outcomes were at least equivalent to screw-fixation at mean follow-up of 4.0 years. LEVEL OF EVIDENCE: Level III.

Plate Versus Lag Screw Only Fixation of Unstable Ankle Fractures Involving the Fibula in Adolescent Patients.

BACKGROUND: Plate fixation has been the traditional technique for fracture repair of unstable ankle injuries with an associated lateral malleolus fracture. Recently, biomechanical and clinical data have demonstrated lag screw only fixation to be an effective alternative to plate fixation in the adult population. This comparison has yet to be studied in the adolescent or pediatric population. The objective of this study was to compare lag screw only fixation with traditional plating for lateral malleolus fractures in adolescents. METHODS: A retrospective review was conducted of 83 adolescents with unstable oblique lateral malleolus fractures treated at a single pediatric level-1 trauma center between 2011 and 2019 with a minimum clinical follow-up until fracture union. Patients were divided into 2 surgical groups: (1) plate fixation (n=51) or (2) lag screw fixation (n=32). Radiographic and clinical outcomes and complications were measured in both groups. RESULTS: All patients in both groups achieved our primary outcome measure of fracture union without loss of reduction. The mean surgical time for subjects treated with a plate was 15 minutes longer (64 vs. 49 min) (P=0.001) and these patients were 3.8 times more likely to have symptomatic implants (P<0.044) than subjects treated with screws. Approximately 50% of the cohort was available by phone for patient-reported outcomes at a mean follow-up of 50 months. The mean Single Assessment Numerical Evaluation scores, Foot and Ankle Ability Measure Activities of Daily Living scores, Foot and Ankle Ability Measure sports scores, and return to sports rates were similar (92 vs. 93, 98.2 vs. 98.1, 93.2 vs. 94.0, 95% vs. 86%, respectively; P>0.05) between the 2 treatment methods. CONCLUSIONS: Lag screw only fixation is a safe and effective procedure for noncomminuted, oblique fibula fractures in the adolescent population as demonstrated by equivalent fracture healing rates without loss of reduction and similar outcome scores. Given these comparable results with the additional benefits of shorter surgical time and less symptomatic implants, lag screw only fixation should be considered as a viable treatment alternative to traditional lateral plating in the adolescent population. LEVEL OF EVIDENCE: Level III.

Reliability of Low-dose Biplanar Radiography in Assessing Pediatric Torsional Pathology.

BACKGROUND: Low-dose biplanar radiographs (LDBRs) significantly reduce ionizing radiation exposure and may be of use in evaluating lower extremity torsion in children. In this study, we evaluated how well femoral and tibial torsional profiles obtained by LDBR correspond with 3-dimensional (3D) computed tomography (CT) and magnetic resonance axial imaging (MRI) in pediatric patients with suspected rotational abnormalities. METHODS: Patients who had both LDBR and CT/MRI studies performed for suspected lower extremity rotational deformities were included. Unlike previous publications, this study focused on patients with lower extremity torsional pathology, and bilateral lower extremities of 17 patients were included. CT/MRI torsion was measured using the Reikerås method, after conversion to 3D reconstructions. The LDBRs were deidentified and sent to the software division of EOS imaging, who created 3D reconstructions and evaluated each reconstruction for the torsional quantification of the femurs and tibiae. These imaging modalities were compared using correlation statistics and Bland-Altman analyses. RESULTS: The mean age of the cohort was 12.1±1.7 years old. Torsional values of the femur were significantly lower in LDBRs versus 3D CT/MRIs at 17.7±15.1 and 23.3±17.3, respectively (P=0.001). Torsional values of the tibia were similar in LDBRs versus 3D CT/MRIs at 23.6±10.6 and 25.3±11.2, respectively (P=0.503). There was a good intermodality agreement between LDBR and 3D CT/MRI torsional values in the femur (intraclass correlation coefficient=0.807) and tibia (intraclass correlation coefficient=0.768). Bland-Altman analyses showed a fixed bias with a mean difference of -5.6±8.8 degrees between femoral torsion measurements in LDBRs versus 3D CT/MRIs (P=0.001); 15% (5/34) of femurs had a clinically significant measurement discrepancy. Fixed bias for LDBR measurements compared with 3D CT/MRIs for the tibia was not observed (P=0.193), however, 12% (4/34) of tibias had a clinically significant measurement discrepancy. CONCLUSION: Although we found strong correlations between torsional values of the femur and tibia measured from LDBRs and 3D CT/MRIs, torsional values of the femur produced from LDBRs were significantly lower than values obtained from 3D CT/MRIs with some notable outliers. LEVEL OF EVIDENCE: Level III.

Functional Outcomes of Unstable Ankle Fractures in Adolescents.

BACKGROUND: The purpose of this study was to describe the functional outcomes and complications of unstable supination external rotation (SER) and pronation external rotation (PER) ankle fractures in adolescents. A secondary outcome was to compare functional outcomes of SER stage IV injuries that were treated definitively with closed reduction and cast application to a similar group of minimally displaced fractures treated with open reduction and internal fixation (ORIF). METHODS: A retrospective review of adolescents aged 10 to 18 years with unstable ankle fractures treated at a single institution between 2009 and 2017 was conducted. All patients had functional outcomes data from the Foot and Ankle Ability Measure obtained at a minimum of 1-year follow-up. RESULTS: In total, 67 adolescents (41 SER, 26 PER) were included (mean follow-up: 52.3±24.8 mo). A total of 56 were treated with ORIF and 11 were closed reduced and casted. No patients treated nonsurgically had a loss of reduction and none required subsequent surgical intervention. Preoperative radiographic predictors of syndesmotic injury (>6 mm of tibiofibular clear space or <2 mm of tibiofibular overlap) were not sensitive and only moderately specific predictors of intraoperative syndesmotic injury. There was no difference in functional outcome between the 11 SER stage IV fractures treated nonoperatively and a group of minimally displaced SER injuries treated with ORIF. Patients with open or partially open physes had better functional outcomes. Patients with syndesmotic injuries, medial malleolus fractures, or fracture-dislocations were not associated with lower functional outcome scores in our adolescent cohort. CONCLUSIONS: Unstable SER and PER injuries in adolescents have favorable functional outcomes at intermediate-term follow-up, though a minority continue to have impaired ankle function. Minimally displaced SER stage IV injuries with near anatomic alignment after closed reduction can be successfully treated with continued closed management, and have no difference in functional outcomes compared with similar injuries treated with ORIF. LEVEL OF EVIDENCE: Level III.

3D Knee Trochlear Morphology Assessment by Magnetic Resonance Imaging in Patients With Normal and Dysplastic Trochleae.

BACKGROUND: Trochlear dysplasia is recognized as a significant risk factor for patellar instability, but current imaging modalities fail to allow full visualization and classification of the complex 3-dimensional (3D) anatomy of the trochlea. The purpose of this study was to elucidate primary differences in trochlear morphology between patients with and without patellar instability by utilizing 3D magnetic resonance imaging (MRI) reconstructions of the trochlea. METHODS: An institutional review board-approved retrospective review included 24 patients with a diagnosis of patellar instability and an age-matched and sex-matched control population of 12 patients. 3D models of the femoral trochlea were created from MRI images and measurements were performed. 3D measurements were trochlear groove volume and surface area that were normalized to the femoral width. 2D measurements were performed throughout the length of the trochlea including the bony and cartilaginous sulcus angles as well as the bony and cartilaginous trochlear depths. Differences were also assessed between sex, skeletal maturity, and trochlear dysplasia severity. RESULTS: Surface topography of the trochlea varied significantly based on location with the trochlea becoming progressively more flat proximally away from the notch (P<0.05). Patients with patella instability had reduced trochlear volumes and trochlear depths compared with control patients (P<0.05). These differences were more pronounced with the cartilaginous measurements as well as more proximally within the trochlea. Patients with high-grade dysplasia had greater reductions in trochlear volumes and depth especially proximally in the trochlea (P<0.05). Once femoral size was standardized, minimal differences were observed based on sex or skeletal maturity (P>0.05). CONCLUSIONS: Novel 3D MRI reconstructions demonstrated that measurements of trochlear morphology varied significantly between patients with and without patellar instability. When trochlear dysplasia is present, it appears to affect the majority of the trochlear surface, but preferentially the proximal extent. Future trochlear dysplasia classification systems may benefit from assessment of articular cartilage surface measures rather than primarily osseous structure measurements. LEVEL OF EVIDENCE: Level III-case-control prognostic study.

Risk Factors for Adverse Radiographic Outcomes After Elastic Stable Intramedullary Nailing of Unstable Diaphyseal Tibia Fractures in Children.

OBJECTIVES: Elastic stable intramedullary nails (ESIN) are commonly utilized to treat unstable pediatric tibia fractures but have been associated with complications. The purpose of this study was to identify risk factors for adverse radiographic outcomes after ESIN of pediatric tibia fractures. METHODS: A retrospective review of all patients who underwent diaphyseal tibia fracture stabilization with ESIN between 2010 and 2018 at 3 pediatric level 1 trauma centers was performed. Inclusion criteria were open growth plates, no intra-articular or physeal fracture involvement, and radiographic follow-up until union. Patient demographics, injury mechanism, fracture characteristics, and implant fill relative to the medullary canal were recorded. Radiographic outcome measures included achievement of and time to union, residual angular deformity, and additional procedures. RESULTS: One hundred seventy-two patients met inclusion criteria and were followed for a mean of 1.2 years. Nonunions were observed in 3% of the patient cohort. Another 10% required >6 months to heal, but did not require further surgical intervention. Angular deformities were common with 57% having a residual deformity ≥5 degrees and 14% having a residual deformity ≥10 degrees. Of the patients with a residual deformity between 5 and 10 degrees, 3% were symptomatic, where as 26% of the patients with a residual deformity ≥10 degrees were symptomatic. Greater angular deformities were associated with open fractures, compartment syndrome, and longer time to union. Patient age, weight, tibial comminution, and canal fill were not associated with nonunions or malunions. CONCLUSIONS: ESIN of pediatric tibia fractures results in reliable healing for a majority of patients, but poses risks for residual angular deformities and delayed healing. Open fractures and compartment syndrome were associated with adverse radiographic outcomes.