Miller TT, Shapiro MA, Schultz E, et al [ North Shore Univ Hosp, Manhasset, NY: North Shore Radiology, Great Neck, NY: Kernan Hosp, Baltimore, Md]
Sonography of Patellar Abnormalities in Children
AJR 171: 739-742, 1998
Sonography, with its ability to show cartilaginous structures, is widely used to examine the unossified hip in suspected developmental dysplasia.
Scans were taken in both the longitudinal and transverse planes as the scan operator flexed and extended the patient’s knee. Examination took less than 10 minutes to perform.
US is recommended as the imaging procedure of choice to determine the extensor mechanism and unossifed patella in young children.
The advantages of sonography over MRI include the following: no need of sedation, speed of examination and ability to compare with the contralateral knee, low cost, and the sonographer’s ability of dynamically assess the extensor mechanism.
It should, by now, be well known that US scan elegantly demonstrate the unossified patella, its tendons, and the nearby surfaces of the femur. Because of the ease of dynamic sonographic imaging, exact clinical questions can be answered for such infants and toddlers.