What causes asymmetrical thigh creases in babies?

Asymmetrical thigh creases—more on one side than the other—may indicate developmental dysplasia of the hip (DDH), including acetabular dysplasia, hip subluxation, or hip dislocation. However, this finding may also simply reflect normal variations in subcutaneous fat distribution.

Nonetheless, regardless of the underlying cause, it is recommended that the child be evaluated at a pediatric health care clinic. For infants under six months of age, hip ultrasound screening is recommended. For children older than six months who exhibit additional positive clinical signs, radiography (X-ray) is indicated to confirm the diagnosis. The following four groups are considered high-risk and warrant particular attention:

1. Children with a family history of hip dislocation;

2. Infants born in abnormal positions—for example, breech presentation—or delivered via cesarean section, who have a significantly higher incidence compared with those delivered vaginally;

3. Female infants;

4. Infants with associated congenital anomalies, such as clubfoot or torticollis—these cases require especially close monitoring.