MRI anatomy and injuries of the fingers.

Magnetic resonance imaging (MRI) diagnosis of underlying finger pathology can be intimidating due to the presence of unique anatomy. The small size of the fingers and the unique orientation of the thumb compared to the fingers also introduce unique demands on the MRI system and the technologists performing the study. This article will review the anatomy pertinent to injuries at the fingers, provide protocol guidance, and discuss pathology encountered at the fingers.

Descriptive Epidemiology From the Research in Osteochondritis Dissecans of the Knee (ROCK) Prospective Cohort.

Background: Osteochondritis dissecans (OCD) occurs most commonly in the knees of young individuals. This condition is known to cause pain and discomfort in the knee and can lead to disability and early knee osteoarthritis. The cause is not well understood, and treatment plans are not well delineated.

Return-to-sport quadriceps strength symmetry impacts 5-year cartilage integrity after anterior cruciate ligament reconstruction: A preliminary analysis.

Quadriceps femoris strength asymmetry at the time of return to sports participation after anterior cruciate ligament (ACL) reconstruction contributes to worse function and asymmetric landing patterns, but the impact on longitudinal outcomes is not known. This study determined if young athletes after ACL reconstruction with quadriceps femoris strength asymmetry at a return to sports clearance would demonstrate markers of knee cartilage degeneration 5 years later compared to those with symmetric quadriceps femoris strength at return to sports. Participants (n = 27) were enrolled at the time of medical clearance for sports participation (baseline testing) and followed for 5 years.

Osteochondritis Dissecans of the Knee: An Interrater Reliability Study of Magnetic Resonance Imaging Characteristics.

Background: Imaging characteristics of osteochondritis dissecans (OCD) lesions quantified by magnetic resonance imaging (MRI) are often used to inform treatment and prognosis. However, the interrater reliability of clinician-driven MRI-based assessment of OCD lesions is not well documented.

Purpose: To determine the interrater reliability of several historical and novel MRI-derived characteristics of OCD of the knee in children.

Impingement syndromes of the ankle and hindfoot.

Ankle impingement refers to a chronic painful mechanical limitation of ankle motion caused by soft-tissue or osseous abnormality affecting the tibiotalar joint or extraarticular soft tissues. Impingement can be associated with a prior single traumatic event or repetitive microtrauma, often in an adolescent with anatomical predisposition. Impingement syndromes at the tibiotalar joint can be subdivided into anterior, anterolateral, anteromedial, posterior or posteromedial.

Lower patient-reported function at 2 years is associated with elevated knee cartilage T1rho and T2 relaxation times at 5 years in young athletes after ACL reconstruction.

Purpose: The purpose was to test the following hypotheses: (1) magnetic resonance imaging (MRI) markers of early knee cartilage degeneration would be present in the involved limb of young athletes after anterior cruciate ligament reconstruction (ACLR) and (2) poor knee function would be associated with MRI markers of cartilage degeneration.

Methods: Twenty-five young athletes after primary, unilateral ACLR (mean age, 16.7 years) were followed to 5-year post-return-to-sport (RTS) clearance, as a part of a larger, prospective cohort study in young athletes post-ACLR.

Imaging assessment of patellar instability and its treatment in children and adolescents.

Transient patellar dislocation is a common entity in children and adolescents, characterized by lateral dislocation of the patella, usually with spontaneous reduction. Many predisposing conditions have been described, including trochlear dysplasia, excessive lateral patellar tilt, patella alta and lateralization of the tibial tuberosity. Associated injuries are bone bruises of the patella and lateral femoral condyle, tears of the medial retinaculum that include the medial patellofemoral ligament (MPFL), tears of the vastus medialis obliquus muscle, injuries of articular cartilage, and intra-articular bodies.

Post-operative imaging of anterior cruciate ligament reconstruction techniques across the spectrum of skeletal maturity.

Due to an increased frequency of anterior cruciate ligament (ACL) injuries in young patients and improved outcomes in athletic performance following ACL reconstruction, surgery is increasingly being performed across the spectrum of skeletal maturity. We present a review of the range of reconstruction techniques performed in skeletally immature patients (physeal sparing techniques, which may involve epiphyseal tunnels or the utilization of an iliotibial band autograft), those performed in patients nearing skeletal maturity (transphyseal techniques), and the more conventional ACL reconstruction techniques performed in skeletally mature adolescents. It is important that radiologists be aware of the range of techniques being performed throughout the spectrum of skeletal maturity in order to accurately characterize the expected post-operative appearance as well as to identify complications, including those unique to this younger population.

Juvenile Osteochondritis Dissecans: Correlation Between Histopathology and MRI.

Objective: The objective of our study was to correlate specimens of juvenile osteochondritis dissecans (OCD) lesions of the knee to MRI examinations to elucidate the histopathologic basis of characteristic imaging features.

Materials And Methods: Five children (three boys and two girls; age range, 12-13 years old) who underwent transarticular biopsy of juvenile OCD lesions of the knee were retrospectively included in this study. Two radiologists reviewed the MRI examinations and a pathologist reviewed the histopathologic specimens and recorded characteristic features.

Avulsion fractures of the pediatric knee.

Although avulsion fractures of the pediatric knee are uncommon, they are important injuries to recognize because they are frequently associated with adjacent soft-tissue and osteocartilaginous abnormalities. Related injuries, which include entrapment of soft-tissue structures, intra-articular fracture extension, and intra-articular loose bodies, can complicate or alter therapy. The most commonly affected soft-tissue structures include the cruciate ligaments, collateral ligaments and supporting tendons, and extensor mechanism and retinacula.

US for diagnosis of musculoskeletal conditions in the young athlete: emphasis on dynamic assessment.

Ultrasonography (US) is increasingly recognized as an important tool for diagnosis and therapeutic management of a variety of musculoskeletal conditions. Advantages of US use in the young athlete include the ability to diagnose dynamic conditions that are occult with other modalities, provide additional diagnostic information, and aid in treatment. Uses of US in young patients include evaluation of acquired musculoskeletal conditions that manifest with symptoms and assessment of congenital variants that may manifest with pain or limitations in activity.

Prenatal Diagnosis of Infantile Myofibroma with Postnatal Imaging Correlation.

Infantile myofibroma is the most common fibrous tumor in infancy. A majority of these lesions are solitary and occur in the head and neck region. Unless visceral sites are involved, the clinical course is typically benign.

Posttreatment imaging of pediatric musculoskeletal tumors.

Pediatric patients who are diagnosed with musculoskeletal tumors often require serial imaging both during and after treatment. Although many of the treatments used in adults overlap with those used in children and adolescents, the growing skeleton presents specific challenges that require a unique approach. Surgical treatment of benign osseous lesions typically requires only curettage and bone grafting, whereas that of osseous malignancies generally consists of wide excision and limb salvage, with either endoprosthetic or biologic reconstruction.

Imaging of osteochondritis dissecans.

Osteochondritis dissecans (OCD) can affect both adults and children, however the imaging characteristics and significance of imaging findings can differ in the juvenile subset with open physes. Radiography and magnetic resonance imaging (MRI) are the primary modalities used to aid in diagnosis, to define a treatment plan, to monitor progress, to assess surgical intervention, and to identify postoperative complications. Newer imaging techniques under continuous development may improve the accuracy of MRI for diagnosis and staging of OCD, and eventually may help to predict the durability of tissue-engineered constructs and cartilage repair.

Rotator cuff tears in children and adolescents: experience at a large pediatric hospital.

Background: Prior literature, limited to small case series and case reports, suggests that rotator cuff tears are rare in adolescents. However, we have identified rotator cuff tears in numerous children and adolescents who have undergone shoulder MRI evaluation.

Objective: The purpose of this study is to describe the prevalence and characteristics of rotator cuff tears in children and adolescents referred for MRI evaluation of the shoulder at a large pediatric hospital and to correlate the presence of rotator cuff tears with concurrent labral pathology, skeletal maturity and patient activity and outcomes.

Feasibility of ultrashort TE (UTE) imaging of children at 1.5 T.

Ultrashort TE (UTE) is a relatively new MRI technique that allows for the visualization of tissue structures with short T2 components that show little or no signal on all conventional MR imaging sequences. This technique, to the best of our knowledge, has been described only in adults and uses a half excitation pulse and radial k-space data acquisition to produce echo times of less than 100 microseconds with no need for additional hardware modifications. We describe the feasibility of using a 2-D UTE sequence in vivo on a routine 1.

Juvenile osteochondritis dissecans: is it a growth disturbance of the secondary physis of the epiphysis?

Objective: The primary physis is responsible for longitudinal bone growth. Similarly, epiphysial growth relies on endochondral ossification from the circumferential secondary physeal [corrected]. injury can result in disruption of normal ossification.

The reliability to determine "healing" in osteochondritis dissecans from radiographic assessment.

Background: Current literature supporting treatment strategies for osteochondritis dissecans (OCD) has limited prognostic utility. Presently, there is no gold standard for an OCD "healing" outcome. Accurate and reliable determination of the OCD healed status on the basis of radiographs would be valuable to provide a guide for evidence-based treatment of OCD.

MRI of radiographically occult ischial apophyseal avulsions.

Background: Acute avulsions of unossified ischial apophyses in children may go undetected on radiography. Therapy includes rest and rehabilitation; however, substantial displacement may require surgery.

Objective: Our purpose is to illustrate the utility of MRI in the detection of these radiographically occult injuries in skeletally immature children.

Focal Periphyseal Edema (FOPE) zone on MRI of the adolescent knee: a potentially painful manifestation of physiologic physeal fusion?

Objective: We have termed an MRI finding in the knees of adolescents characterized by a focal bone marrow edema pattern centered about the closing physis a "FOPE"-that is, focal periphyseal edema-zone. The cause of this appearance is unknown. Therefore, the purpose of this article is to review the MRI appearance of the FOPE zone and to postulate a causative mechanism.

MRI of displaced meniscal fragments.

A torn meniscus frequently requires surgical fixation or debridement as definitive treatment. Meniscal tears with associated fragment displacement, such as bucket handle and flap tears, can be difficult to recognize and accurately describe on MRI, and displaced fragments can be challenging to identify at surgery. A displaced meniscal fragment can be obscured by synovium or be in a location not usually evaluated at arthroscopy.

CT evaluation of extensor tendon entrapment as a complication of a distal radial fracture in a child.

Extensor indicis proprius (EIP) entrapment is a rare complication of a distal radial fracture. We report an 11-year-old with limited flexion of her index finger 1 year after a distal radial fracture. The utility of cross-sectional imaging in the diagnosis and preoperative planning of this complication is presented.

MR findings of synovial disease in children and young adults: Part 1.

Synovial diseases in children can be classified into normal structures as potential sources of pathology (synovial folds: plicae, infrapatellar fat pad clefts); noninfectious synovial proliferation (juvenile idiopathic arthritis, hemophilic arthropathy, lipoma arborescens, synovial osteochondromatosis, pigmented villonodular synovitis, reactive synovitis), and infectious synovial proliferation, deposition disease, vascular malformations, malignancy (including metastasis) and intra-articular/periarticular cysts and cyst-like structures (ganglia). Familiarity with characteristic MR imaging findings of synovial diseases in children and young adults will enable a more confident diagnosis for earlier intervention and directed therapy. The first part of this paper will cover potential pathology of normal synovial structures as well as noninfectious synovial proliferation.