• appendicitis / intussusception (donut) / lymphadenitis / nephritis

DDH Heupdysplasie

Highlights

• Risk factors for DDH include positive family history, being firstborn, being a girl, breech presentation, and the mother having oligohydramnios.
• The left hip is more often affected.
• The natural history of DDH depends on the type and degree of abnormality.
• Most DDH identified in the newborn period represents laxity and immaturity; 60% to 80% of DDH identified by physical examination and 90% identified by ultrasound resolve spontaneously.
• Diagnosis depends on physical examination and radiography or ultrasound.
• The American Academy of Pediatrics recommends clinical hip evaluation at every newborn well-baby visit, starting at 1 to 2 weeks, then at 2, 4, 6, 9, and 12 months.
• Clues to DDH include risk factors, asymmetric thigh skin folds, and thigh shortening.
• The Ortolani and Barlow tests are performed for screening.
• The Ortolani test causes a "clunk" to be detected when the displaced femoral head slips into the acetabulum.
• The Barlow test can elicit a dislocation followed by reduction and identifies some unstable hips missed by the Ortolani test.
• In children older than 3 months, these tests are less likely to have positive results.
• Limitation of hip abduction and asymmetric skin folds are more useful.
• Once a child is walking, a typical limp and toe-walking on the affected side are also indications of DDH.
• In bilateral DDH, a waddling gait may be present.
• Radiographs are of limited value in the first month because the femoral head is composed of cartilage.
• By 4 to 6 months, radiographs are more reliable and should be performed in the neutral position, with dislocation or subluxation of the femoral head recognized by evaluation of the ossific nucleus of the femoral head and metaphysis to the acetabulum.
• Radiographic examination is made by visual assessment.
• There is no established role for radiographs in routine screening for DDH, but screening may be considered in infants at risk for DDH after 6 weeks of age.
• Ultrasound was introduced by Graf in the coronal plane, and the North American standard for hip ultrasound recommends a coronal view in Graf format and a transverse view with the hip flexed and without modified Barlow stress maneuver.
• Hips are classified by Graf as: type 1, requiring no treatment or follow-up; type 2, requiring no treatment but requiring follow-up (subtypes are a, b, c, and d); type 3, with low displacement, requiring immediate treatment; and type 4, with high displacement, requiring immediate treatment.
• The American Academy of Pediatrics recommends hip ultrasound for girl infants born in breech position and optional imaging for boys born in breech position or girls with a positive DDH family history.
• Routine screening of all infants by ultrasound is not recommended.
• Selected ultrasound screening with positive physical examination findings has been shown to reduce abduction splinting and cost.
• Computed tomography is primarily used for follow-up after surgery and not for diagnosis of DDH.
• Magnetic resonance imaging may be used in complex dislocations with suspected avascular necrosis.
• Arthrography is used to evaluate lateral displacement of the femoral head after closed reduction.
• All neonates should receive generalized physical evaluation; neonatal screening has reduced late presentation of DDH.
• There is agreement that dislocated hips should be treated and stable "clicking" hips should be followed.
• The management of hips with unstable (lax but displaced) hips remains controversial, with some advocating early treatment and others recommending follow-up.

Clinical Implications

• DDH affects 1.5 in 1000 white children, with a lower incidence in blacks, and is 4 to 8 times more common in girls.
• Physical examination, but not routine radiography, ultrasound, or other radiologic tests, are indicated for screening all children for DDH.