E4707. Tiny Bones, Big Challenges: Pediatric Musculoskeletal Radiology Essentials for the Adult Specialist
  1. Neil Stewart; Scottish Rite for Children Hospital
  2. Matthew Hammer; UT Southwestern Medical Center
  3. Andrew Ross; University of Wisconsin-Madison
  4. Vivek Kalia; Scottish Rite for Children Hospital
The modern musculoskeletal (MSK) radiology fellowship offers exposure to both the diagnostic and interventional sides of adult patients. When MSK radiologists encounter pediatric cases, there is often less familiarity with conditions that occur in immature skeletal anatomy. It is important for all MSK radiologists to have a working knowledge of cases across the age spectrum. Fortunately, gaining familiarity with the most common pediatric conditions and their unique imaging features need not be daunting.

Educational Goals / Teaching Points
This work focuses on presenting the most high-yield pediatric MSK diagnoses, such as buckle fractures, bowing deformities, physeal injuries, stress-related injuries, slipped capital femoral epiphysis (SCFE), Legg-Calve-Perthes disease, and osteomyelitis will serve the adult-trained radiologist in many clinical settings, such as cross-covering on call. Understanding the appearance of normal developmental processes and variants is key for interpreting pediatric examinations. Ossification centers, physeal appearances, and their growth dynamics across the age spectrum become critical.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Compromise of the primary growth plate may lead to limb length discrepancies and altered biomechanics. Distal fractures of the radius and ulna, especially those caused by fall on outstretched hand (FOOSH), are the most common fracture of the upper limb in children, often presenting as buckle fractures or incomplete compression fractures. These can be subtle to the untrained eye. Overuse injuries are a common primary physeal injury in child athletes. The proximal humeral physis (throwing sports), distal radial physis (gymnasts), and distal femoral physis are the most typically injured. SCFE is the result of anterosuperior or posterior displacement of the femoral head with respect to the metaphysis. Male (2:1) adolescents 10–13 years old, Black, and overweight children are especially susceptible. SCFE should be considered when a Klein line drawn from the lateral border of the femoral neck no longer intersects the epiphysis. Periphyseal edema may be present. Legg-Calve-Perthe’s disease (LCPD) is an atraumatic, osteonecrosis considered to be a result of ischemia that leads to degeneration of the femoral head. More common in boys (5:1), patients often present with new-onset limp with or without relapsing groin and knee pain, and 85–90% of cases are bilateral. Early LCPD may be seen as enlargement of the joint space with or without subchondral fracture. Fragmentation or subchondral collapse of the femoral head are indicative of late LCPD. Osteomyelitis most commonly occurs in children as a hematogenous infection often seen in the long bones. Bone marrow edema resulting from osteomyelitis can be seen as early as 1 day after infection onset by low T1-enchanced signal in bone marrow compared to the adjacent metaphysis and skeletal muscle.

Familiarity with recognizing these common pediatric conditions important findings should be part of a MSK radiologist’s toolkit.