Imaging Review of Normal and Abnormal Skeletal Maturation

MRI of Pediatric Foot and Ankle Conditions

The increase in competitive sports practice among children and lack of ionizing radiation have resulted in a higher demand for MRI examinations. MRI of the children skeleton has some particularities that can lead orthopedists, pediatricians, and radiologists to diagnostic errors. The foot and ankle have several bones with abundant radiolucent and high signal intensity cartilage in several ossification centers, apophysis and physis, that can make this interpretation even harder. The present revision aims to show, how to differentiate between normal developmental findings and anatomic variants from pathologic conditions, whether mechanical, inflammatory, infectious, or neoplastic.

Pediatric Shoulder Girdle

The pediatric shoulder girdle is a complex anatomical structure uniting the upper extremity and trunk. The osseous structures, their articulations, and the surrounding soft tissue support structures (muscles, tendons, and ligaments) allow for a wide range of motion at the shoulder. Growth and maturation of the components at the shoulder girdle vary, particularly the osseous structures. This characteristic renders interpretation of imaging of the pediatric shoulder girdle more challenging because normal or variant anatomy can be confused for pathology. We review the physiologic growth and maturation of the shoulder girdle with special emphasis on the development of the bones and their articulations. The role of various imaging modalities and the common osseous and soft tissue variants in the pediatric shoulder are also discussed.

Clinical value of low-dose three-dimensional reconstruction by multi-slice spiral computed tomography and by traditional X-ray in the diagnosis of distal radius epiphyseal injury in children

OBJECTIVE

To compare the clinical value of multi-slice spiral computed tomography (MSCT) low-dose three-dimensional reconstruction and traditional X-ray in the auxiliary diagnosis of distal radius epiphyseal injury in children.

METHODS

A retrospective analysis was performed on 105 children with distal radius bone scale injury (classified by Salter-Harris classification) admitted from March 2020 to June 2022. All children underwent MSCT three-dimensional reconstruction examination and traditional X-ray examination. The detection rate of epiphyseal injury of the distal radius was compared, along with the resolution, sensitivity and specificity. The image clarity and display degree of bone structure were analyzed. The radiation dose-related indicators and the time required for diagnosis were compared.

RESULTS

The detection rate and diagnostic accuracy of MSCT (100%, 92.38%) was significantly higher than that of X-ray (76.19%, 64.76%). In terms of radiation dose index, the volume dose index CTDI of MSCT ranged from 1-5 mGy while the X-ray group ranged from 5-10 mGy. The dose length product (DLP) value of the MSCT group was lower than in the X-ray group (20-100 mGy·cm vs. 50-150 mGy·cm). The diagnostic scan time for MSCT was shorter than that of conventional X-ray. The acceptance rate with MSCT was 99%, significantly higher than that with conventional X-ray (85%).

CONCLUSIONS

Low-dose three-dimensional reconstruction of MSCT in the diagnosis of epiphyseal injury of distal radius in children shows significant advantages over traditional CT in the detection rate, diagnostic accuracy, postoperative reduction quality evaluation, and radiation dose.

Pictorial review: challenges in distinguishing bilateral metaphyseal marrow abnormalities on magnetic resonance imaging

The paediatric metaphysis is afflicted by a wide range of pathological processes as it is the most metabolically active and well-vascularised part of the developing skeleton. This review focuses on metaphyseal marrow signal change detected with magnetic resonance imaging, which is most often occult on radiographs. When bilateral, these imaging appearances frequently present a diagnostic quandary. This review assists the radiologist to confidently dismiss physiological signal change and confidently work through the differential diagnosis. This is achieved by illustrating a practical method of classifying signal change into four categories: physiological red marrow, red marrow reconversion, marrow infiltration, and oedema-like marrow signal intensity. In doing so, various pathological entities are reviewed along with imaging pearls and next-step investigations.

Neoplastic and Non-neoplastic Bone Lesions of the Knee

Numerous anatomical variants are described around the knee, many of which look like bony lesions, so it is important to know them to avoid unnecessary complementary tests and inadequate management. Likewise, several alterations in relation to normal development can also simulate bone lesions.However, numerous pathologic processes frequently affect the knee, including traumatic, inflammatory, infectious, and tumor pathology. Many of these entities show typical radiologic features that facilitate their diagnosis. In other cases, a correct differential diagnosis is necessary for proper clinical management.Despite the availability of increasingly advanced imaging techniques, plain radiography is still the technique of choice in the initial study of many of these pathologies. This article reviews the radiologic characteristics of tumor and nontumor lesions that may appear around the knee to make a correct diagnosis and avoid unnecessary complementary radiologic examinations and inadequate clinical management.

[Pediatric developmental disorders of the musculoskeletal system]

CLINICAL/METHODICAL ISSUE

In pediatric musculoskeletal disorders, a distinction is made between normal and abnormal development.

STANDARD RADIOLOGICAL METHODS

X‑ray examination is the standard diagnostic procedure.

METHODOLOGICAL INNOVATIONS

Cross-sectional imaging, such as magnetic resonance imaging (MRI), computed tomography (CT), and ultrasonography (US) are increasingly used.

PERFORMANCE

X‑ray imaging is still the examination method of choice but can be supplemented by cross-sectional imaging depending on clinical situation.

ACHIEVEMENTS

Cross-sectional imaging is helpful and necessary in many cases but significantly more time-consuming and costly than x‑ray examinations.

PRACTICAL RECOMMENDATIONS

Initially standard x‑rays should be taken, which can then be supplemented with cross-sectional imaging depending on the result and clinical question (MRI and US are preferred as there is no radiation).

[MR Imaging Features of Pediatric Bone Marrow]

MRI plays a crucial role in bone marrow (BM) assessment, and has very high sensitivity in diagnosing marrow disorders. However, for radiologists who may not frequently encounter pediatric imaging, distinguishing pathologic BM lesion from normal BM can be challenging. Conditions involving the BM in pediatric patients, such as leukemia and metastatic neuroblastoma, often manifest with diverse musculoskeletal symptoms and may be diagnosed using musculoskeletal MRI examinations. Accurate interpretation of pediatric MRI requires not only an understanding of the normal composition of BM but also an awareness of agerelated developmental changes in the marrow and familiarity with conditions that commonly involve pediatric BM. We aim to describe the composition of normal BM and outline the normal and abnormal MRI findings in pediatric BM. Additionally, we aim to present clinical cases of malignant BM disorders including leukemia, neuroblastoma metastasis, and other malignant BM disorders.

[Normal Development and Variants in Pediatric Bone]

Normal variants refer to imaging findings that are generally asymptomatic and discovered incidentally, yet may exhibit findings similar to those observed in pathological conditions. Recognizing normal variants in pediatric bone requires comprehension of the developmental process of long tubular bones and secondary ossification centers. Familiarity with various radiological findings of normal variants can prevent unnecessary follow-up imaging tests, as well as incorrect diagnosis and treatment. In this review, we will discuss the characteristic imaging findings of normal variants seen in growing pediatric bones, along with strategies for distinguishing them from pathologic conditions.

Apophyseal injuries in soccer players

Soccer is the most popular sport worldwide, and it is associated with high injury rates, with most of these injuries occurring in the lower extremities. Particularly, in youth soccer players with immature skeleton, the physeal plate is two to five times weaker than the surrounding fibrous structures, and therefore more vulnerable to injury. The physeal plate consists of epiphyses and apophyses, with the former serving as tendon attachment sites and being subject to traction forces. There are two types of apophyseal injury: (i) apophyseal avulsion, which consists of an acute separation across the physeal plate; and (ii) apophysitis, an injury caused by chronic and repetitive contraction of musculotendon unit, leading to inflammation of the growth plate cartilage. Apophyses of the hip and pelvis are the most commonly injured in youth soccer players, due to vigorous contractions during sports activities and the fact that they tend to fuse later compared to other epiphyseal centers, making them more susceptible to injury. In this review, we will discuss the anatomy of lower limb apophyses and clinical and imaging findings of apophyseal injuries in youth soccer players, as well as briefly review treatment options and complications.

Previously unreported X-ray findings associated with distal toe pain in children

While children undergo skeletal maturation, it is difficult to distinguish between normal variants and abnormalities of the epiphysis and acrophysis on radiological images. Abnormalities in the epiphysis and acrophysis of the toe phalanx have not been reported yet. Here, we describe a series of abnormalities in the epiphysis and acrophysis of the fourth and fifth toe phalanges, including an investigation of their pathogenesis. We evaluated patients suspected of having bone tumors at a local orthopedic clinic because of abnormal findings of the toe phalanx between the distal and middle phalanx on plain radiographs. The site of the lesion, duration of pain until the hospital visit, history of trauma and sports, treatment, and clinical course were investigated. A total of seven patients (five boys and two girls) with a mean age of 10 years (range 9-16) were included. In all cases, a circular erosive radiolucent image was present between the distal and middle phalanx. In two cases, the fourth toe was affected, and in five cases, the fifth toe was affected. Six patients showed improvements with conservative treatment using shoe insoles. In one case, surgical treatment was performed for persistent pain. Histological examination of the fibrous tissue collected from the circular erosive radiolucent area revealed normal bone and slightly degenerated hyaline cartilage. This is the first report on the abnormalities of the epiphysis and acrophysis of the toe phalanx, which is termed as Shintaniwakino disease. A better understanding of this disease may aid in the avoidance of unnecessary treatment.

Radiographic assessment of the pubic symphysis in elite male adolescent football players: Development and reliability of the Maturing Adolescent Pubic Symphysis (MAPS) classification

INTRODUCTION

The pubic symphysis is susceptible to growth related injuries long after the adolescent growth spurt. Our study describes the radiographic maturation of the pubic symphysis on pelvic radiographs in adolescent football players and introduces the Maturing Adolescent Pubic Symphysis classification (MAPS classification).

METHODS

Anteroposterior pelvic radiographs of 105 healthy adolescent male football players between 12 and 24 years old were used to develop the classification system. The radiological scoring of the symphyseal joint was developed over five rounds. The final MAPS classification items were scored in random order by two experienced readers, blinded to the age of the participant and to each other's scoring. The inter- and intra-rater reliability were examined using weighted kappa (κ).

RESULTS

We developed a classification system with descriptive definitions and an accompanying pictorial atlas. The symphyseal joint was divided into three regions: the superior corners, and the upper and lower regions of the joint line. Inter-rater reliability was substantial to almost perfect: superior region: κ = 0.70 (95% CI 0.60---0.79), upper region of the joint line: κ = 0.89 (95% CI 0.86---0.92), lower region of the joint line: κ = 0.65 (95% CI 0.55---0.75). The intra-observer reliability showed similar results.

CONCLUSION

The Maturing Adolescent Pubic Symphysis classification (MAPS classification) is a reliable descriptive classification of the radiographic maturation of the pubic symphysis joint in athletic males. The stages can provide a basis for understanding in clinical practice and will allow future research in this field.

MRI of Pediatric Foot and Ankle Conditions

The increase in competitive sports practice among children and lack of ionizing radiation have resulted in a higher demand for MRI examinations. MRI of the children skeleton has some particularities that can lead orthopedists, pediatricians, and radiologists to diagnostic errors. The foot and ankle have several bones with abundant radiolucent and high signal intensity cartilage in several ossification centers, apophysis and physis, that can make this interpretation even harder. The present revision aims to show, how to differentiate between normal developmental findings and anatomic variants from pathologic conditions, whether mechanical, inflammatory, infectious, or neoplastic.

Clinical characteristics of 1124 children with epiphyseal fractures

BACKGROUND

In this study, to provide a theoretical basis for understanding the clinical characteristics of epiphyseal fractures in children and improving their management, we explored and analyzed the proportions of different types of epiphyseal fractures in children and evaluated the causes of injury and epidemiological characteristics.

METHODS

We retrospectively analyzed children younger than 18 years with fresh epiphyseal fractures who were admitted to our hospital from July 2015 to February 2020. Demographic information, injury mechanisms, fracture characteristics, fracture classification and surgical information were collected.

RESULTS

A total of 1124 pediatric patients (1147 epiphyseal fractures), including 789 boys and 335 girls, were included in this study. Epiphyseal fractures were classified as Salter-Harris type II (1002 cases), type IV (105 cases), type III (25 cases), Salter-Harris type I (14 cases), and Salter-Harris type V (1 case). The number of fracture sites peaked in the adolescent group (440 cases). The most three common sites of epiphyseal fractures were the distal radius (460 cases) in which Salter-Harris type II fractures were the most common (454 cases) and Salter-Harris type I (3 cases), Salter-Harris type IV (2 cases), Salter-Harris type III was the least common (1 case). Followed by phalanges of fingers (233 cases) in which Salter-Harris type II fractures were the most common (224 cases) and Salter-Harris type IV (4 cases), Salter-Harris type I (3 cases), Salter-Harris type III fractures were the least common (2 cases). Distal humerus (146 cases) in which Salter-Harris type II fractures were the most common (95 cases), followed by Salter-Harris type IV (49 cases), Salter-Harris type I fractures were the least common (2 cases). The most three important causes of fractures were falls (720 patients), car accident injuries (68 patients), and basketball falls (43 patients). Among the 1124 children with epiphyseal fractures, 1058 were treated mainly by surgery and the ratio of open and closed reduction was 1:5.3. Eighty-eight patients showed an interval > 72 h between the injury and the hospital visit. Among these 88 patients, the most common fracture type was distal radial epiphyseal fracture (32 cases), and all fractures were of Salter-Harris type II.

CONCLUSIONS

The epidemiological characteristics of epiphyseal fractures in children indicate the need to strengthen health and safety education and protective measures to prevent the occurrence of these fractures in children. In addition, emergency surgeons and orthopedic surgeons in general hospitals should strengthen their basic knowledge of diagnosing and treating epiphyseal injuries in children to reduce missed diagnoses, misdiagnoses or malpractice.

Emergency MRI in Spine Trauma of Children and Adolescents-A Pictorial Review

Severe spinal trauma is uncommon in the pediatric population, but due to the potentially devastating consequences of missed injury, it poses a diagnostic challenge in emergency departments. Diagnostic imaging is often needed to exclude or confirm the injury and to assess its extent. Magnetic resonance imaging (MRI) offers an excellent view of both bony and soft tissue structures and their traumatic findings without exposing children to ionizing radiation. Our pictorial review aims to demonstrate the typical traumatic findings, physiological phenomena, and potential pitfalls of emergency MRI in the trauma of the growing spine.

MR Imaging of the Developing Pediatric Marrow: An Overview of Pearls and Pitfalls

The dynamic and developing pediatric skeleton is a well-elucidated process that occurs in a stepwise faction. Normal development has been reliably tracked and described with Magnetic Resonance (MR) imaging. The recognition of the normal patterns of skeletal development is essential, as normal development may mimic pathology and vice versa. The authors review normal skeleton maturation and the corollary imaging findings while highlighting common marrow imaging pitfalls and pathology.