Sonographic diagnostics and sonography-guided treatment of hip dysplasia in infancy

摘要

Sonographic diagnostics of hip dysplasia according to Graf and sonography-guided-treatment represent milestones in the recognition and treatment of this disorder. The ultrasound examination enables the diagnosis to be made, thus ensuring that treatment is initiated on the 1st day of life. Besides the method-specific advantages of sonography (repeatability, avoiding radiation, costs, availability) the possibility for early therapy represents a decisive benefit. Based on the method-developed and first described by -Reinhard Graf, a distinction is made between 5 main types (I, II, D, III, and IV) and 12 different subtypes. Type I (Ia or Ib) corresponds to a healthy joint that needs no treatment. Types D, III (IIIa or IIIb), and IV joints are decentered, i.e., abnormal joints, which always require treatment. All type II hips are borderline cases, which can be either abnormal or healthy depending on age and findings. The diagnosis is reached based on precise sonographic visualization, description of the findings, and verification of the description by determining a bone angle "alpha" as a measure of dysplasia and a bone angle "beta" as a measure of instability. Two images are obtained for each joint, one of which is used for measurement. When treatment is begun as early as possible in the first few days of life with an abduction bandage, overhead extension, Pavlik harness, or cast, success rates of more than 90 can be obtained even in severely dysplastic joints. Surgical procedures are the exception and are usually ascribed to delayed diagnosis. The measure of a healed hip joint is achievement of a good bony acetabulum and a bone angle of >60 degrees. Only this constellation facilitates adequate joint congruence and is prerequisite for physiological joint function. Sonographic examination of infants has been integrated into the U3 screening program for early detection of preventable disorders since 1995. Admittedly, this initially does ensure that the infants are all screened; however, in cases with pathological findings this results in delayed treatment onset after the U3 examination in the 4th to 5th week of life. Only when the method of sonographic diagnostics for detecting dysplasia is widely employed in a precise and timely manner can the best possible outcome of diagnostics and treatment of hip dysplasia be guaranteed in the interest of these young patients.