Injuries and Conditions of the Extensor Mechanism of the Pediatric Knee

Abstract

The extensor mechanism of the knee is essential to ambulation and is subject to a number of traumatic, congenital, and inflammatory processes. In the pediatric population, the spectrum of pathologic conditions affecting the extensor mechanism is specific to skeletally immature patients. In addition, certain congenital and developmental disorders may further predispose the knee extensor mechanism to injury. The pathologic processes can be subdivided into categories: conditions of the attachments and insertions of the quadriceps and patellar tendons, conditions of the patella, conditions of the quadriceps muscle group, and avulsions of the superior attachments of the quadriceps. Cases of conditions affecting the extensor mechanism of the pediatric knee were collected at two large trauma centers, and the clinical and radiologic features were reviewed. Initial evaluation of these conditions is performed with radiography, but magnetic resonance imaging has evolved into a useful adjunct for assessing the soft tissues for a more precise evaluation of the true extent of an injury, thereby affecting decisions about surgical intervention and prognosis.

Osteochondral Lesions of Major Joints

“…It is related to throwing activities. The trochlea, radial head ( Figure 1) and the olecranon are other sites that can be involved [15,16]. The capitellar pseudodefect and trochlear groove, along with a focal area devoid of cartilage at the junction of the coronoid and olecranon articular surfaces of the ulna in the trochlear notch should not be confused with OCL.…”

Imaging Review of Adolescent Tibial Tuberosity Fractures

“…AP and lateral views are essential to make the diagnosis, but the lateral view best depicts the size and displacement of the fragment [1]. Oblique radiographs of the proximal tibia can be useful to better demonstrate the tubercle as it lies just lateral to the midline [15].…”

The Pearls and Pitfalls of Magnetic Resonance Imaging of the Lower Extremity

“…11 This is a clinical diagnosis, and MRI is usually only obtained to exclude other causes of anterior knee pain, such as patellar tendinosis or tearing. However, the characteristic appearance of fragmented and irregular bone along and adjacent to the tibial tuberosity, with adjacent edema and inflammation in the soft tissues, would support the clinical …”