Developmental Dysplasia of the Hip (DDH)

Key Risk Factors

Epidemiological studies have established several major risk factors that mandate dedicated ultrasound screening, regardless of normal physical examination findings.

• Breech Presentation: This is the single most significant risk factor. The intrauterine malposition, particularly the frank breech posture with extended knees, forces the fetal hips into extreme flexion, geometrically limiting normal rotational mobility and acetabular development.
• Positive Family History: A first-degree relative with DDH significantly increases the risk.
• Female Gender: Females are roughly four to six times more susceptible, likely due to increased fetal sensitivity to maternal relaxin hormones which physiologically prepare the maternal pelvis for delivery but inadvertently cause fetal ligamentous laxity.
• Oligohydramnios: A lack of protective amniotic fluid creates a restrictive intrauterine environment, mechanically compressing the fetal limbs and impairing normal joint articulation.

Physical Examination: Barlow and Ortolani

Newborn routine checks invariably include two provocative clinical maneuvers designed to physically assess hip stability.

• Barlow Maneuver: This is the 'dislocating' test. The examiner flexes and adducts the infant's hip while applying gentle posterior pressure to the knee. A positive test is characterized by a palpable 'clunk' as the femoral head is driven backwards out of a shallow acetabulum.
• Ortolani Maneuver: This is the 'reducing' test. The examiner abducts the hip while applying anterior pressure behind the greater trochanter. A positive test is the palpable sensation of the dislocated femoral head returning forward into the true acetabulum.