To Graf or not to Graf: Paediatric hip ultrasound

Abstract

Sonography is the imaging of choice for the initial assessment of a patient who presents with suspected developmental dysplasia of the hip (DDH). DDH is a condition that results in abnormal development of the femoral head and acetabulum. When detected early using ultrasound the condition is easily treated via non-invasive bracing of the legs to enable the acetabular cartilage to mold and develop over a period of months until normal. A late detection or missed DDH can result in the need for surgery and therefore the potential for early onset osteoarthritis later in life. Ultrasound has proven to be a great screening resource for DDH however it is known to be extremely operator dependent. It is therefore very important that sonographers ensure they know the techniques, diagnostic criteria and classifications, as well as pitfalls when performing hip sonography. One such pitfall I have seen over the years is the incorrect use of the Graf classification. Graf angles and diagnostic criteria are extremely useful in the diagnosis and follow up of DDH if utilized and applied correctly. This presentation will demonstrate how to focus on technique and landmarks, when and how to apply Graf's diagnostic measurements, and most importantly how to avoid the common pitfalls.