Postoperative Access and Compliance Following Medial Patellofemoral Ligament Reconstruction in Hispanic Adolescents Mirrors the Non-Hispanic Adolescent Population.

BACKGROUND: Disparity in surgical care of patellar instability patients has not been fully investigated in the adolescent Hispanic population. This demographic has been shown to have differences in their care, including a lower rate of surgical treatment for patellar instability. Socioeconomic factors have been cited as a factor that influences patient outcomes and its relationship with ethnicity in context of patellar instability has not been evaluated. METHODS: Review performed of patients <19 years of age who underwent MPFL reconstruction between September 2008 and December 2015. Demographics, patient median household income data, and clinical variables were collected. Generalized linear mixed model (GLMM) with subject as random effects factor was utilized to evaluate differences between ethnicity groups due to nonindependence of data. It was then expanded to incorporate interactions between ethnicity and income. RESULTS: Ninety-five patellar dislocation events met criteria in 85 adolescents (mean age: 15.5 y). Thirty-four (40%) adolescents identified as Hispanic. In univariate analysis no differences were found between Hispanic and non-Hispanic patients. The multivariate GLMM demonstrated a significant interaction between ethnicity and income. The Hispanic group in the >100% State median income category had the highest rate of postoperative clinic appointments attended (P=0.019). The Hispanic group in the <100% State median income category had the lowest rate of physical therapy appointments attended (P=0.044). No differences were observed for duration of follow-up (P=0.57) or final Kujala score (P=0.75). CONCLUSIONS: Hispanic ethnicity alone is not associated with inferior postoperative management after MPFL reconstruction in adolescents. However, when socioeconomic status is considered, Hispanic patients of lower-income backgrounds are found to have lower compliance with postoperative rehab recommendations. LEVEL OF EVIDENCE: Level III.

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.

Common Pediatric Fractures for Community Orthopaedic Specialists: Fix Them or Ship Them?

It is important to focus on common pediatric fractures seen in community emergency rooms, including supracondylar humerus, elbow, forearm, distal radius, and femoral shaft fractures, along with periarticular fractures around the knee and ankle in children. The principles of surgical and nonsurgical management of these fractures are based on the fracture type and age of the patient. The orthopaedic surgeon should be aware of important tips and tricks to help manage these injuries and be familiar with common complications that may occur when these injuries are encountered during trauma call.

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.

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.

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.

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.

What's New in the Management of Pediatric Anterior Cruciate Ligament Tears and Tibial Spine Fractures.

As the number of pediatric and adolescent patients participating in sports continues to increase, so too does the incidence of anterior cruciate ligament (ACL) tears in this population. There is increasing research on pediatric and adolescent ACL tears; hundreds of articles on the topic have been published in the past few years alone. It is important to highlight the most pertinent information in the past decade. In discussing pediatric ACL tears, it is also important to review tibial spine fractures. These injuries are rightfully grouped together because tibial spine fractures often occur with a mechanism of injury similar to that of ACL tears, but typically in a younger age group. Because management is different, understanding the similarities and differences between the two pathologies is important. Recent updates on the epidemiology, diagnosis, management, and outcomes of both pediatric ACL tears and tibial spine fractures need to be reviewed.

What's New in Osteochondritis Dissecans of the Knee, Elbow, and Ankle.

Osteochondritis dissecans is a condition of the subchondral bone, with secondary effects on the articular cartilage. It most commonly affects the knee, elbow, and ankle and is typically seen in young, active populations. Many osteochondritis dissecans lesions are asymptomatic, but more advanced lesions can cause pain, swelling, and mechanical symptoms. Multiple treatment options have been proposed, including nonsurgical and surgical approaches. It is important to be aware of the epidemiology, presenting symptoms, and indications for nonsurgical and surgical treatment options for osteochondritis dissecans of the knee, elbow, and ankle.

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.

Functional Outcomes of Arthroscopic Os Trigonum Excision in Adolescents.

BACKGROUND: Outcomes of symptomatic os trigonum excision have been well described as a successful treatment in adults; however, the literature lacks information on standardized longer term functional outcomes in the pediatric population. This study intends to report functional outcomes of arthroscopic os trigonum excision in adolescents who failed conservative management, with the hypothesis that these younger patients would have similar, successful outcomes of adult patients. METHODS: A retrospective study was performed on adolescents who underwent arthroscopic os trigonum excision at a single institution between 2011 and 2017. Patient demographic, clinical history, radiographic, and operative data were documented. Outcome measures included the Foot and Ankle Ability Measure (FAAM) score comprised of the Activities of Daily Living (ADL) and Sports subscales, Single Assessment Numeric Evaluation (SANE) score, ability to return to the same level of sport, and any additional foot/ankle surgery. RESULTS: Ten patients (12 ankles) met criteria with a mean age at surgery of 15.4 years (range, 12 to 18 y) and a mean follow-up of 6.5 years (range, 2.8 to 9.1 y). Mean FAAM ADL subscale, Sports subscale, and SANE scores were 91.0±15.5, 76.3±29.1, and 88.6±15.1, respectively. A chronic duration of symptoms before surgery was associated with a lower FAAM Sports current level of function score (P=0.032). Four patients (40%) discontinued their sport due to continued ankle issues and reported significantly lower FAAM ADL subscale (P=0.01), Sports subscale (P<0.001), and SANE scores (P=0.002). CONCLUSIONS: Os trigonum syndrome in the adolescent population may not have the same rate of success as that seen in adult athletes over the long-term. However, if proven to be refractory to conservative measures and surgical intervention is indicated, patients and their families should be counseled about the risk for persistent ankle symptoms and the possibility that they may not be able to return to their previous level of sport. LEVEL OF EVIDENCE: Level IV-case series.

Editorial Commentary: Osteochondritis Dissecans of the Knee: The Great Confounder.

The management of osteochondritis dissecans (OCD) continues to baffle even the savviest of surgeons, with unclear etiology, unknown relationship of presentation to outcome, bewildering response to various treatments, and frustratingly difficult-to-predict prognosis. Whether skeletal immaturity may be indicative of surgical success, at least when it comes to lesions requiring screw fixation, remains debatable. Treatment may include activity modification, drilling, fixation, or osteochondral replacement of OCD lesions in the knee. Regardless, each OCD lesion must be followed until osseous integration is confirmed by imaging -otherwise, progression of disease to osteoarthritis is likely.

What's New in Pediatric Orthopaedic Trauma: The Upper Extremity.

BACKGROUND: Upper extremity fractures are the most common fractures in children. Many high-quality studies have been reported regarding operative and nonoperative treatment of different upper extremity fractures in children. This review will summarize the literature on 4 major upper extremity fractures in children over the past 5 years. METHODS: PubMed and Embase databases were queried for publications in the English language on supracondylar humerus (SCH) fractures, lateral humeral condyle fractures, medial epicondyle fractures, and clavicle fractures from January 1, 2013 until November 1, 2018. Papers believed to yield significant findings to our profession were included in this review. RESULTS: A total of 1150 studies were related to the search terms, and after cursory assessment, the authors elected to fully review 30 papers for this publication: 12 related to SCH fractures, 10 related to lateral condyle humerus fractures, 3 related to medial epicondyle humerus fractures, and 5 involving clavicle fractures. The level of evidence for these studies was either level III or IV. CONCLUSIONS: SCH fractures are increasingly being treated at trauma centers or pediatric hospitals in the United States. The rate of open reduction in this fracture type is decreasing overall, but the flexion type SCH fractures (especially in the setting of ulnar nerve injury) continue to be at increased risk of requiring open reduction. There has been a paradigm shift in the treatment of lateral condyle humerus fractures, wherein authors have demonstrated successful management with closed reduction and percutaneous pinning when an adjunct arthrogram is performed demonstrating articular congruity. More studies are needed to find the optimal treatment for displaced medial epicondyle and clavicle fractures in adolescents, as results to date do not necessarily mirror those seen in the adult population. LEVEL OF EVIDENCE: Level IV.

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.

Medial Epicondyle Fractures: Biomechanical Evaluation and Clinical Comparison of 3 Fixation Methods Used in Pediatric Patients.

BACKGROUND: Screw fixation is the most commonly employed fixation strategy for displaced medial epicondyle fractures, but in younger patients with minimal ossification, the fracture fragment may not accommodate a screw. In these situations, Kirschner-wires (K-wire) or suture anchors may be utilized as alternatives. The purposes of this study were to examine the biomechanical properties of medial epicondyle fractures fixed with a screw, K-wires, or suture anchors, to evaluate clinical outcomes and complications of patients 10 years of age or younger treated with these approaches, and to perform a cost-analysis. METHODS: Biomechanical assessment: Immature pig forelimbs underwent an osteotomy through the medial epicondyle apophysis, simulating a fracture. These were then fixed with a screw, K-wires or suture anchors. Cyclic elongation (mm), displacement (mm), load to failure (N), and stiffness (N/mm) were assessed. Clinical assessment: a retrospective review was performed of patients 10 years of age or younger with a medial epicondyle fracture fixed with these strategies. Radiographic outcomes, postoperative data and complications were compared. These data were used to perform a cost-analysis of each treatment approach. RESULTS: Biomechanically, screws were stronger (P=0.047) and stiffer (P=0.01) than the other constructs. Clinically, 51 patients met inclusion criteria (screw=27, wires=11, anchor=13). Patients treated with K-wires were younger (P<0.05) and patients treated with screw fixation had a shorter casting duration (P=0.008). Irrespective of treatment strategy, all fractures healed (100%) and only 1 patient in the screw group lost reduction. Clinical outcomes and complications were similar between groups, but the suture anchor group was less likely to require a second surgery for implant removal (P<0.05). This lower reoperation rate led to a cost-saving of 10%. CONCLUSIONS: Biomechanically, all 3 approaches provided initial fixation exceeding the forces observed across the elbow joint with routine motion. The screw construct was the strongest and stiffest. Clinically, all 3 strategies were acceptable, with screw fixation offering a shorter casting duration, but greater implant removal need with higher associated costs.

Magnetic resonance imaging predictors of shoulder instability in adolescents.

BACKGROUND: Managing recurrent shoulder instability in an athlete of any age is challenging. The pediatric literature regarding recurrence of instability is difficult to interpret because of the variable treatment protocols and varying ages. The adult literature suggests that bone loss on the humerus, glenoid or both, as detected by CT, has high rates of recurrence following surgical intervention. OBJECTIVE: The purpose of this study was to evaluate risk factors for recurrence following arthroscopic capsulorrhaphy in adolescent athletes using preoperative MR arthrograms. MATERIALS AND METHODS: We reviewed a retrospective shoulder instability database for adolescents (age ≤18 years), who underwent an isolated arthroscopic capsulorrhaphy from 2006 to 2011. We recorded preoperative MRI measurements regarding the dimensions of the glenohumeral joint, as well as glenoid, humeral and labral pathologies. We performed statistical analysis to determine MRI findings that might have predicted recurrence of shoulder instability following capsulorrhaphy. RESULTS: We reviewed a total of 50 patients (13-18 years) and found 22 patients (44%) to have recurrent instability following capsulorrhaphy. Presence of glenoid bone loss or a bipolar bone lesion (defined as bone loss on both the glenoid and humerus) significantly predicted recurrence of shoulder instability (both P=0.03). There was not a threshold size of glenoid bone loss or bipolar lesion that predicted recurrence. All remaining glenohumeral dimensions or presence or size of an isolated Hill-Sachs did not significantly predict recurrence of instability. CONCLUSION: Athletes ≤18 years old have a high rate of failure following arthroscopic capsulorrhaphy in the presence of glenoid bone loss or a bipolar lesion on MRI. Surgeons should consider addressing these lesions in adolescent athletes with shoulder instability. Additionally, MRI is a valid imaging tool to diagnose and measure osseous lesions of the shoulder.

Under Pressure: The Utility of Spacers in Univalved Fiberglass Casts.

BACKGROUND: Univalving fiberglass casts after fracture manipulation or extremity surgery reduces the risk of developing compartment syndrome (CS). Previous experiments have demonstrated that univalving decreases intracompartmental pressures (ICPs), but increases the risk for loss of fracture reduction due to altering the mechanical properties of the cast. The purpose of this study was to correlate cast valve width within a univalved cast model to decreasing ICP. METHODS: Saline bags (1 L) were covered with stockinette, Webril, and fiberglass tape then connected to an arterial pressure line monitor. Resting pressure was recorded. A water column was added to simulate 2 groups (n=5 each) of clinical CS: low pressure CS (LPCS range, 28 to 31 mm Hg) and high pressure CS (HPCS, range, 64 to 68 mm Hg). After the designated pressure was reached, the fiberglass was cut (stockinette and Webril remained intact). Cast spacers were inserted into each univalve and secured with varying widths: position #1 (3 mm wide), #2 (6 mm), #3 (9 mm), and #4 (12 mm). Pressure was recorded after cutting the fiberglass and following each spacer placement. RESULTS: In LPCS and HPCS groups, after univalve and placement of spacer position #1, pressure dropped by a mean of 52% and 58%, respectively. Spacer #2, decreased the pressure by a mean of 78% and 80%, respectively. Both spacer sizes significantly decreased the underlying pressure in both groups. Spacer #3 and #4 progressively reduced pressure within the cast, but not statistically significantly more than the previous spacer widths. CONCLUSIONS: This experimental model replicates the iatrogenic elevation in interstitial compartment pressure due to rigid cast application, not necessarily a self-sustained true CS. Increasing the univalved cast spread by ≥9 mm of the initial cast diameter will reduce pressure to a pre-CS level; however, a spread of only 6 mm can effectively reduce the pressure to <30 mm Hg depending on the initial elevated ICP. Cutting the Webril and stockinette in our model yielded a pressure decrease of 91% and 94% from the starting experimental pressure in the LPCS and the HPCS groups, respectively. CLINICAL RELEVANCE: Although the utility of splitting fiberglass casts has been previously demonstrated, we present evidence highlighting the benefit of spacing the split by at least 6 to 9 mm.

Adolescent clavicle nonunions: potential risk factors and surgical management.

BACKGROUND: Clavicle nonunions in adolescent patients are exceedingly rare. The purpose of this study was to evaluate a series of clavicle nonunions from a pediatric multicenter study group to assess potential risk factors and treatment outcomes. METHODS: A retrospective review of all clavicle nonunions in patients younger than 19 years was performed at 9 pediatric hospitals between 2006 and 2016. Demographic and surgical data were documented. Radiographs were evaluated for initial fracture classification, displacement, shortening, angulation, and nonunion type. Clinical outcomes were evaluated, including rate of healing, time to union, return to sports, and complications. Risk factors for nonunion were assessed by comparing the study cohort with a separate cohort of age-matched patients with a diaphyseal clavicle fracture. RESULTS: There were 25 nonunions (mean age, 14.5 years; range, 10.0-18.9 years) identified, all of which underwent surgical fixation. Most fractures were completely displaced (68%) initially, but 21% were partially displaced and 11% were nondisplaced. Bone grafting was performed in 24 of 25 cases, typically using the hypertrophic callus. Radiographic healing was achieved in 96% of cases. One patient (4%) required 2 additional procedures to achieve union. The primary risk factor for development of a nonunion was a previous history of an ipsilateral clavicle fracture. CONCLUSIONS: Clavicle nonunions can occur in the adolescent population but are an uncommon clinical entity. The majority occur in male patients with displaced fractures, many of whom have sustained previous fractures of the same clavicle. High rates of union were achieved with plate fixation and the use of bone graft.