Changes in tissue sodium concentration and sodium relaxation times during the maturation of human knee cartilage: Ex vivo 23 Na MRI study at 10.5 T.

PURPOSE: To evaluate the influence of skeletal maturation on sodium (23 Na) MRI relaxation parameters and the accuracy of tissue sodium concentration (TSC) quantification in human knee cartilage. METHODS: Twelve pediatric knee specimens were imaged with whole-body 10.5 T MRI using a density-adapted 3D radial projection sequence to evaluate 23 Na parameters: B1 + , T1 , biexponential T 2 * $$ {\mathrm{T}}_2^{\ast } $$ , and TSC. Water, collagen, and sulfated glycosaminoglycan (sGAG) content were calculated from osteochondral biopsies. The TSC was corrected for B1 + , relaxation, and water content. The literature-based TSC (TSCLB ) used previously published values for corrections, whereas the specimen-specific TSC (TSCSP ) used measurements from individual specimens. 23 Na parameters were evaluated in eight cartilage compartments segmented on proton images. Associations between 23 Na parameters, TSCLB - TSCSP difference, biochemical content, and age were determined. RESULTS: From birth to 12 years, cartilage water content decreased by 18%; collagen increased by 59%; and sGAG decreased by 36% (all R2 ≥ 0.557). The short T 2 * $$ {\mathrm{T}}_2^{\ast } $$ ( T 2 * S $$ {{\mathrm{T}}_2^{\ast}}_{\mathrm{S}} $$ ) decreased by 72%, and the signal fraction relaxing with T 2 * S $$ {{\mathrm{T}}_2^{\ast}}_{\mathrm{S}} $$ ( fT 2 * S $$ {{\mathrm{fT}}_2^{\ast}}_{\mathrm{S}} $$ ) increased by 55% during the first 5 years but remained relatively stable after that. TSCSP was significantly correlated with sGAG content from biopsies (R2 = 0.739). Depending on age, TSCLB showed higher or lower values than TSCSP . The TSCLB - TSCSP difference was significantly correlated with T 2 * S $$ {{\mathrm{T}}_2^{\ast}}_{\mathrm{S}} $$ (R2 = 0.850), fT 2 * S $$ {{\mathrm{fT}}_2^{\ast}}_{\mathrm{S}} $$ (R2 = 0.651), and water content (R2 = 0.738). CONCLUSION: TSC and relaxation parameters measured with 23 Na MRI provide noninvasive information about changes in sGAG content and collagen matrix during cartilage maturation. Cartilage TSC quantification assuming fixed relaxation may be feasible in children older than 5 years.

MRI of patellar stabilizers: Anatomic visibility, inter-reader reliability, and intra-reader reproducibility of primary and secondary ligament anatomy.

OBJECTIVE: To compare MRI features of medial and lateral patellar stabilizers in patients with and without patellar instability. METHODS: Retrospective study of 196 patients (mean age, 33.1 ± 18.5 years; 119 women) after diagnosis of patellar instability (cohort-1, acute patellar dislocation; cohort-2, chronic patellar maltracking) or no patellar instability (cohort-3, acute ACL rupture; cohort-4, chronic medial meniscus tear). On MRI, four medial and four lateral stabilizers were evaluated for visibility and injury by three readers independently. Inter- and intra-reader agreement was determined. RESULTS: Medial and lateral patellofemoral ligaments (MPFL and LPFL) were mostly or fully visualized in all cases (100%). Of the secondary patellar stabilizers, the medial patellotibial ligament was mostly or fully visualized in 166 cases (84.7%). Other secondary stabilizers were mostly or fully visualized in only a minority of cases (range, 0.5-32.1%). Injury scores for all four medial stabilizers were higher in patients with acute patellar dislocation than the other 3 cohorts (p < .05). Visibility inter- and intra-reader agreement was good for medial stabilizers (κ 0.61-0.78) and moderate-to-good for lateral stabilizers (κ 0.40-0.72). Injury inter- and intra-reader agreement was moderate-to-excellent for medial stabilizers (κ 0.43-0.90) and poor-to-moderate for lateral stabilizers (κ 0-0.50). CONCLUSION: The MPFL and LPFL were well visualized on MRI while the secondary stabilizers were less frequently visualized. The secondary stabilizers were more frequently visualized medially than laterally, and patellotibial ligaments were more frequently visualized compared to the other secondary stabilizers. Injury to the medial stabilizers was more common with acute patellar dislocation than with chronic patellar maltracking or other knee injuries.

Medial femoral condyle OCD (osteochondritis dissecans): correlation between imaging and arthroscopy.

Osteochondritis dissecans (OCD) describes a pathologic condition centered at the osteochondral junction that may result in an unstable subchondral fragment (progeny), disruption of the overlying cartilage, which may separate from the underlying parent bone. It is one of the causes of chronic knee pain in children and young adults. The current literature on OCD lesions focuses primarily on the medial femoral condyle (MFC), but inconsistent use of terminology, particularly in the distinction of OCD lesions between skeletally immature and mature patients has created uncertainty regarding imaging workup, treatment, and long-term prognosis. This article reviews the pathophysiology of MFC OCD lesions, highlighting the role of endochondral ossification at the secondary growth plate of the immature femoral condyles, the rationale behind the imaging work-up, and key imaging findings that can distinguish between stable lesions, unstable lesions, and physiologic variants. This overview also provides a case-based review to introduce imaging correlates with the ROCK (Research in Osteochondritis of the Knee) arthroscopic classification.

Patella and Trochlea Osteochondritis Dissecans: Demographics and Treatment Paradigms.

OBJECTIVE: Previous research on patellar and trochlear groove osteochondritis dissecans (OCD) is limited by small sample sizes. This study aims to describe the presentation of patients with OCD lesions of the patella and trochlea and characterize the outcomes of operative and nonoperative treatments. METHODS: This retrospective cohort study identified all patients from a single institution from 2008 to 2021 with patellar and/or trochlear OCD lesions. Patients were excluded from the study if surgical records were unavailable or if the patient had knee surgery for a different injury at index surgery or in the 12 months postoperative. Minimum follow-up was 12 months. Outcomes included a return to sports (RTS), pain resolution, radiographic healing, and treatment "success" (defined as full RTS, complete pain resolution, and full healing on imaging). RESULTS: A total of 68 patients (75 knees) were included-45 (60%) with patellar OCD and 30 (40%) with trochlear. Of the patients, 69% were males. The median age at knee OCD diagnosis was 14 years. At the final follow-up, 62% of knees (n = 44) recovered sufficiently to allow a full RTS and 54% of knees (n = 39) had full pain resolution. Of the 46 knees with radiographic imaging at least 1 year apart, 63% had full healing of the lesion. There was no significant difference in RTS, pain resolution, radiographic healing, or overall success when comparing treatments. CONCLUSIONS: This study provides valuable epidemiologic demographic and outcome data regarding the scarcely reported patellar and trochlear OCD. While over half of patients fully returned to sports and reported full pain resolution, a large proportion continued to experience symptoms over a year after presentation. Future research should aim to better define the treatment algorithms for these OCD subtypes. LEVEL OF EVIDENCE: Level III.

Consensus-Based Guidelines for Management of First-Time Patellar Dislocation in Adolescents.

BACKGROUND: The management of first-time patellar dislocation remains variable, with limited evidence to support or compare different operative and nonoperative modalities. The primary aim was to establish consensus-based guidelines for different components of nonoperative treatment following a first-time patellar dislocation. The secondary aim was to develop guidelines related to management after failed nonoperative treatment. The tertiary aim was to establish consensus-based guidelines for the management of first-time patellar dislocation with a concomitant osteochondral fracture. METHODS: A 29-question, multiple-choice, case-based survey was developed by 20 members of the Patellofemoral Research Interest Group of the Pediatric Research in Sports Medicine Society. The survey consisted of questions related to demographic information, management of first-time patellar dislocation without an osteochondral fracture, and management of first-time patellar dislocation with a 2 cm osteochondral fracture. The survey underwent 2 rounds of iterations by Patellofemoral Research Interest Group members and the final survey was administered to Pediatric Research in Sports Medicine members, using REDCap. Consensus-based guidelines were generated when more than 66% of respondents chose the same answer. RESULTS: Seventy-nine of 157 (50%) eligible members responded. Sixty-one were orthopaedic surgeons and 18 were primary sports medicine physicians. Eleven consensus-based guidelines were generated based on survey responses. Those that met the criteria for consensus included initial knee radiographs (99% consensus), nonoperative treatment for first-time patellar dislocation without an osteochondral fracture (99%), physical therapy starting within the first month postinjury (99%), with return to sport after 2 to 4 months (68%) with a brace (75%) and further follow-up as needed (75%). Surgical treatment was recommended if there were patellar subluxation episodes after 6 months of nonoperative treatment (84%). Patellar stabilization should be considered for a first-time dislocation with an osteochondral fracture (81.5%). CONCLUSION: Consensus-based guidelines offer recommendations for the management of first-time patellar dislocation with or without an osteochondral fracture. Several changing trends and areas of disagreement were noted in clinical practice. CLINICAL RELEVANCE: In the absence of high-level evidence, consensus-based guidelines may aid in clinical decision-making when treating patients following a first-time patellar dislocation. These guidelines highlight the evolving trends in clinical practice for the management of first-time patellar dislocation. Areas not reaching consensus serve as topics for future research.

Knee MRI: Meniscus Roots, Ramps, Repairs, and Repercussions.

Menisci play an essential role in maintaining normal pain-free function of the knee. While there are decades of MRI literature on the tears involving the meniscus body and horns, there is now a surge in knowledge regarding injuries at the meniscus roots and periphery. The authors briefly highlight new insights into meniscus anatomy and then summarize recent developments in the understanding of meniscus injuries that matter, emphasizing meniscus injuries at the root and peripheral (eg, ramp) regions that may be missed easily at MRI and arthroscopy. Root and ramp tears are important to diagnose because they may be amenable to repair. However, if these tears are left untreated, ongoing pain and accelerated cartilage degeneration may ensue. The posterior roots of the medial and lateral menisci are most commonly affected by injury, and each of these injuries is associated with distinctive clinical profiles, MRI findings, and tear patterns. Specific diagnostic pitfalls can make the roots challenging to evaluate, including MRI artifacts and anatomic variations. As with root tears, MRI interpretation and orthopedic treatment have important differences for injuries at the medial versus lateral meniscus (LM) periphery (located at or near the meniscocapsular junction). Medially, ramp lesions typically occur in the setting of an anterior cruciate ligament rupture and are generally classified into five patterns. Laterally, the meniscocapsular junction may be injured in association with tibial plateau fractures, but disruption of the popliteomeniscal fascicles may also result in a hypermobile LM. Updated knowledge of the meniscus root and ramp tears is crucial in optimizing diagnostic imaging before repair and understanding the clinical repercussions. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available in the Online Learning Center.

Patellar Tracking: An Old Problem with New Insights.

Patellofemoral pain and instability are common indications for imaging that are encountered in everyday practice. The authors comprehensively review key aspects of patellofemoral instability pertinent to radiologists that can be seen before the onset of osteoarthritis, highlighting the anatomy, clinical evaluation, diagnostic imaging, and treatment. Regarding the anatomy, the medial patellofemoral ligament (MPFL) is the primary static soft-tissue restraint to lateral patellar displacement and is commonly reconstructed surgically in patients with MPFL dysfunction and patellar instability. Osteoarticular abnormalities that predispose individuals to patellar instability include patellar malalignment, trochlear dysplasia, and tibial tubercle lateralization. Clinically, patients with patellar instability may be divided into two broad groups with imaging findings that sometimes overlap: patients with a history of overt patellar instability after a traumatic event (eg, dislocation, subluxation) and patients without such a history. In terms of imaging, radiography is generally the initial examination of choice, and MRI is the most common cross-sectional examination performed preoperatively. For all imaging techniques, there has been a proliferation of published radiologic measurement methods. The authors summarize the most common validated measurements for patellar malalignment, trochlear dysplasia, and tibial tubercle lateralization. Given that static imaging is inherently limited in the evaluation of patellar motion, dynamic imaging with US, CT, or MRI may be requested by some surgeons. The primary treatment strategy for patellofemoral pain is conservative. Surgical treatment options include MPFL reconstruction with or without osseous corrections such as trochleoplasty and tibial tubercle osteotomy. Postoperative complications evaluated at imaging include patellar fracture, graft failure, graft malposition, and medial patellar subluxation. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Pediatric meniscus morphology varies with age: a cadaveric study.

PURPOSE: In adolescent patients, meniscal tear injury can occur either in isolation (e.g., discoid lateral meniscus tears) or in association with other traumatic injuries including tibial eminence fracture or ACL tear. Damage to meniscal integrity has been shown to increase contact pressure in articular cartilage, increasing risk of early onset osteoarthritis. In symptomatic patients failing conservative management, surgical intervention via meniscus repair or meniscus transplant is indicated. The purpose of this study was to evaluate the radial dimensions of pediatric menisci throughout development. The hypothesis was that the average radial meniscus dimensions will increase as specimen age increases, and mean medial and lateral region measurements will increase at a linear rate. METHODS: Seventy-eight skeletally immature knee cadaver specimens under age 12 years were included in this study. The meniscal specimens were photographed in the axial view with ruler in the plane of the tibial plateau and analyzed using computer-aided design (CAD) software (Autodesk Fusion 360). Measurements were taken from inner to outer meniscus rims at five 45 degree intervals using the clockface as a reference (12:00, 1:30, 3:00, 4:30, 6:00), and total area of meniscus and tibial plateau was recorded. Generalized linear models were used to evaluate the associations of radial width measurements with age, tibial coverage, and lateral vs. medial meniscus widths. RESULTS: All radial width measurements increased significantly with specimen age (p ≤ 0.002), and all lateral-medial meniscal widths increased (p < 0.001). The anterior zones of the meniscus were found to increase at the slowest rate compared to other regions. Tibial plateau coverage was found to not significantly vary with age. CONCLUSIONS: Meniscus radial width and lateral-medial meniscus width are related to age. The anterior width of the meniscus varied least with age. Improved anatomic understanding may help surgeons more effectively plan for meniscus repair, discoid resection/saucerization/repair, and also support appropriate selection of meniscus allograft for transplantation.

Evaluating the Readability and Quality of Online Patient Education Materials for Pediatric ACL Tears.

BACKGROUND: As the rate of anterior cruciate ligament (ACL) tears increases in children, the internet has become a major source of information and education. In the United States, the average adult reads at about an eighth grade level. The National Institutes of Health recommends that patient education materials do not exceed a sixth-grade reading level. Therefore, the most accessed resources on the internet should be created with this in mind. The purpose of this study is to assess the readability and quality of online patient resources for pediatric ACL tears. METHODS: Google was queried using the term "Pediatric ACL Tear" on May 26, 2022. The most popular sites were identified through page one of a Google search. All content was evaluated to assure information was directed toward patients. To determine reading difficulty, the most widely accepted readability tests: Flesch Reading Ease Index, Flesch-Kincaid Grade Level, and Gunning Fog Index were calculated through plain text in Microsoft Word and URL in online readability checker Readable.io. RESULTS: The average grade level for all resources was above the recommended reading level based on both Microsoft Word and Readable.io calculations. Each source exceeded the NIH recommendation by 2.6 grade levels on average (Mean grade level readability was 8.6 ± 1.9). Four of the 6 sites were above the average US reading level, exceeding the eighth grade by an average of 1.5 grade levels. All 6 sites analyzed had a mean DISCERN score of 61.9, meeting the 'good quality' criteria. CONCLUSION: The most readily available online materials for Pediatric ACL tears were of 'good quality' but above both the NIH-recommended readability level and the average US adult reading level. With the increasing need for treatment of ACL tears in pediatric and adolescent patients and greater internet accessibility in these populations, it is important to consider the readability of these resources in support of increased health literacy and improved outcomes. CLINICAL RELEVANCE: It is important for physicians treating young patients with ACL tears to be aware of all sources of information and support, including content shared online as these platforms are increasingly utilized, especially by patients and families of lower socioeconomic status.

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.

Developmental Dysplasia of the Hip: An Examination of Care Practices of Pediatricians.

OBJECTIVE: To evaluate the decision making processes of pediatricians regarding diagnosis and management of developmental dysplasia of the hip (DDH) by conducting a survey of pediatricians in the United States. STUDY DESIGN: An electronic survey was sent to multiple American Academy of Pediatrics state chapters and academic pediatrics groups, and responses were received from pediatricians in 10 states. The survey included demographics, guideline use, clinical scenarios, and referrals/imaging practices. The number of responses to each survey question and their relative frequencies were calculated. RESULTS: We received 139 responses and included 126 in our analyses. Only 50% of the responding pediatricians (63 of 126) practiced in an institution that endorses a care pathway for DDH. Only 5.6% of the pediatricians (7 of 125) have referred patients at 12-18 months between diagnosis and management to a specialist for suspected DDH, and 9.5% (12 of 125) have referred patients between 6 and 9 months. Almost one-quarter of the pediatricians (23%; 29 of 126) cited "hip click" as an abnormality that would prompt them to refer a patient to a specialist, and 72.2% (91 of 126) indicated that family history of DDH warrants an ultrasound regardless of the physical examination findings. Moreover, 10.3% of the surveyed pediatricians (13 of 126) reported being only "somewhat" or "moderately" familiar with the Barlow and Ortolani maneuvers. CONCLUSIONS: The results of this study indicate that there is an opportunity to better distribute and implement DDH guidelines. The large number of pediatrician respondents who would not refer patients to a specialist or order imaging studies appropriately represents an opportunity for education. The implementation of a care map with standard referral and imaging practices could improve the care of patients with DDH.

Quality Measures for Pediatric Orthopaedic Surgery: A Systematic Review.

BACKGROUND: Quality measures provide a way to assess health care delivery and to identify areas for improvement that can inform patient care delivery. When operationalized by a hospital or a payer, quality measures can also be tied to physician or hospital reimbursement. Prior work on quality measures in orthopaedic surgery have identified substantial gaps in measurement portfolios and have highlighted areas for future measure development. This study aims to identify the portfolio of quality measures in pediatric orthopaedic surgery. METHODS: We used methodology of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and reviewed PubMed/ MEDLINE and EMBASE, the American Academy of Orthopaedic Surgery (AAOS), National Quality Forum (NQF), and the Agency for Healthcare Research and Quality (AHRQ), for quality measures and candidate quality measures. Quality measure and candidate quality measures were categorized as structure, process, or outcome. Measures were also classified into 1 of the 6 National Quality Strategy priorities (safety, effective, patient centered, timely, efficient, and equitable). RESULTS: A review of PubMed/EMBASE returned 1640 potential quality measures and articles. A review of AAOS, NQF, and AHRQ databases found 80 potential quality measures. After screening we found a total of 18 quality measures and candidate quality measures specifically for pediatric orthopaedic surgery. Quality measures addressed conditions such as supracondylar humerus fractures, developmental dysplasia of the hip, and osteochondritis dissecans. There were 10 process measures, 8 outcome measure, and 0 structure measures. When we categorized by National Quality Strategy priorities and found 50% (9/18) were effective clinical care, 44% (8/18) were person and care-giver centered experience and outcomes, 6% (1/18) were efficient use of resources. CONCLUSIONS: There are few quality measures and candidate quality measures to assess pediatric orthopaedic surgery. Of the quality measure available, process measures are relatively over-represented. Pediatric orthopaedic surgeons can lead the development of outcome (eg, patient-reported outcomes after surgery) and structure measures (eg, subspecialty training certification) to assess quality of care in pediatric orthopaedic surgery. LEVEL OF EVIDENCE: Level II-systematic review.

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.

Strategies and Tools to Enhance Patient Safety: HROs, HEROs, and Safety Culture.

INTRODUCTION: The Institute of Medicine has defined multiple domains to improve safety, efficiency, and effectiveness of health care. High-Reliability Organizations (HROs) address these issues and promote safety/reliability at the highest level. METHODS: HROs create a bottom-up, top-down culture that focuses upon continuous improvement by withholding blame on individuals yet requiring all members to be accountable for continuous improvement. RESULTS: Supporting staff to speak up, identify, and engage on the path to perfect care and zero harm are elements of a safety culture. In addition to safety, HROs can also focus on effectiveness and efficiency. This may be accomplished by creating consistent care practices that reduce irrational variation, decrease complexity, and lower risk. DISCUSSION: Developing a culture focused upon reliability, safety, and staff resilience is critical for HROs. HROs support and empower all staff to be vigilant and report concerns about any issue related to safety and support the development of a "Safety Culture." HROs focus upon safety will be enhanced by an expanded focus upon effectiveness and efficiency to improve value. A focus on standard clinical practices and clinician integration into the supply chain will help organizations produce better value and be an essential tool to reduce complexity and risk within health care systems.

Developmental Dysplasia of the Hip: An Examination of Care Practices of Pediatric Orthopaedic Surgeons in North America.

BACKGROUND: Developmental dysplasia of the hip (DDH) is a common condition, affecting 1% to 2% of full-term infants. The American Academy of Orthopaedic Surgeons (AAOS) and American Academy of Pediatrics have published guidelines detailing best practices for DDH screening and treatment. The purpose of this survey was to determine DDH treatment practices of pediatric orthopaedic surgeons in North America. METHODS: We queried orthopaedic surgeon members of the Pediatric Orthopaedic Society of North America (POSNA) about referral patterns, treatment practices, and use of DDH guidelines. The survey included demographics, clinical scenarios, referrals patterns, and ultrasound practices. RESULTS: Of the 1392 members of POSNA, we received 432 total responses and included 353 in statistical analyses. Results show that 68% (233/342) of surgeons practice in an institution that does not endorse a standard care pathway for DDH. Of surgeons who personally use a DDH care pathway, the AAOS guidelines were most cited (143/353, 41%). The majority (94%, 316/337) of surgeons do not believe that universal ultrasound screening should be adopted in the United States. Responses regarding ultrasound screening for "high risk" infants as outlined by AAOS varied based on risk factor. Many (57%, 200/353) surgeons have performed initial evaluations for patients over 12 months of age. While 80% (260/327) of orthopaedic surgeons believe that primary care providers are referring patients appropriately, only 57% (183/323) believe that primary care providers are ordering imaging studies appropriately. CONCLUSIONS: Results from this survey of POSNA membership indicate an opportunity to better distribute and implement DDH guidelines. In addition, the implementation of a care map with a focus on standard referral and imaging practices could improve the care of patients with DDH by: (1) reducing the total cost of care, (2) increasing the use of appropriate imaging, (3) increasing timely referral for DDH care, and (4) reducing the presentation rate of walking age DDH patients. LEVEL OF EVIDENCE: The level of evidence rating for this survey-based study is level IV.

Anatomic Dissection and CT Imaging of the Anterior Cruciate and Medial Collateral Ligament Footprint Anatomy in Skeletally Immature Cadaver Knees.

BACKGROUND: Anterior cruciate ligament (ACL) and medial collateral ligament (MCL) injuries in skeletally immature patients are increasingly recognized and surgically treated. However, the relationship between the footprint anatomy and the physes are not clearly defined. The purpose of this study was to identify the origin and insertion of the ACL and MCL, and define the footprint anatomy in relation to the physes in skeletally immature knees. METHODS: Twenty-nine skeletally immature knees from 16 human cadaver specimens were dissected and divided into 2 groups: group A (aged 2 to 5 y), and group B (aged 7 to 11 y). Metallic markers were placed to mark the femoral and tibial attachments of the ACL and MCL. Computed tomography scans were obtained for each specimen used to measure the distance from the center of the ligament footprints to the respective distal femoral and proximal tibial physes. RESULTS: The median distance from the ACL femoral epiphyseal origin to the distal femoral physis was 0.30 cm (interquartile range, 0.20 to 0.50 cm) and 0.70 cm (interquartile range, 0.45 to 0.90 cm) for groups A and B, respectively. The median distance from the ACL epiphyseal tibial insertion to the proximal tibial physis for groups A and B were 1.50 cm (interquartile range, 1.40 to 1.60 cm) and 1.80 cm (interquartile range, 1.60 to 1.85 cm), respectively. The median distance from the MCL femoral origin on the epiphysis to the distal femoral physis was 1.20 cm (interquartile range, 1.00 to 1.20 cm) and 0.85 cm (interquartile range, 0.63 to 1.00 cm) for groups A and B, respectively. The median distance from the MCL insertion on the tibial metaphysis to the tibial physis was 3.05 cm (interquartile range, 2.63 to 3.30 cm) and 4.80 cm (interquartile range, 3.90 to 5.10 cm) for groups A and B, respectively. CONCLUSION: Surgical reconstruction is a common treatment for ACL injury. Computed tomography scanning of pediatric tissue clearly defines the location of the ACL and MCL with respect to the femoral and tibial physes, and may guide surgeons for physeal respecting procedures. CLINICAL RELEVANCE: In addition to ACL reconstruction, recent basic science and clinical research suggest that ACL repair may be more commonly performed in the future. MCL repair and reconstruction is also occasionally required in skeletally immature patients. This information may be useful to help surgeons avoid or minimize physeal injury during ACL/MCL reconstructions and/or repair in skeletally immature patients.

Patellar-Trochlear Morphology in Pediatric Patients From 2 to 11 Years of Age: A Descriptive Analysis Based on Computed Tomography Scanning.

BACKGROUND: Despite the critical role the trochlea plays in patellofemoral (PF) pathology, the development of the trochlea is poorly understood. The purpose of this study was 2-fold: (1) Describe quantitative osseous and soft tissue anatomy of the patella and trochlea in skeletally immature cadaveric specimens utilizing known measurements used in PF instability, and (2) evaluate additional measurement techniques in the sagittal plane as they relate to PF morphologic development. METHODS: Thirty-one skeletally immature fresh frozen cadaveric knees between the ages of 2 and 11 years old were evaluated using 0.625 mm computed tomography scans. In the axial plane, measurements included condylar height asymmetry, trochlear facet asymmetry, trochlear depth, osseous sulcus angle, cartilaginous sulcus angle, patella sulcus angle, and tibial tubercle-trochlear groove distance. In the sagittal plane, measurements included previously undescribed measurements of trochlear length and condylar height asymmetry which are based on the anterior femoral cortex. RESULTS: Analysis of trochlear morphology using condylar height asymmetry (both axial and sagittal), trochlear facet asymmetry, and trochlear depth and length demonstrated an increase in the size of the medial and lateral trochlea as age increased. There was more variability in the change of size of the medial trochlea (height, length, and facet length) than the lateral trochlea. The osseous sulcus angle, cartilaginous sulcus angle, and patella sulcus angle decreased (became deeper) with age until after 8 years and then plateaued. CONCLUSIONS: This cadaveric analysis demonstrated that there is an increase in the medial and lateral trochlear height as age increased by all measurements analyzed. The findings also demonstrate that the shape of the patella and trochlea change concurrently, which suggests that there may be interplay between the 2 during development. These new sagittal measurement techniques evaluating the medial, central, and lateral trochlear height and length with respect to age may help guide clinicians when investigating patellar instability in skeletally immature patients. LEVELS OF EVIDENCE: Level IV.

Editorial Commentary: Anterolateral Ligament-Anatomy, Evaluation, and Future Applications to Knee Stability.

Magnetic resonance imaging evaluation of anterolateral ligament injury may be reliable for individuals experienced and trained to identify it, but it does not reference a diagnostic gold standard. The structural anatomy and radiographic diagnosis may differ from those of more traditional ligaments, which should influence concepts of reconstruction.

The Pediatric Orthopaedic Society of North America (POSNA) Adopts a Member Health and Wellness Charter.

The Pediatric Orthopaedic Society of North America took actions to address the well-being of its members. The epidemic of physician burnout interferes with the delivery of high-quality care that our patients and families need and deserve, and at the same time places the care-providers at an increased risk of depression and suicide. The actions taken by Pediatric Orthopaedic Society of North America serve as a model for other professional medical societies to emulate.