Is prematurity a risk factor for developmental dysplasia of the hip? A systematic review and meta-analysis

Developmental dysplasia of the hip (DDH) is the most common orthopedic disorder in newborns. Early recognition and diagnosis are critical to prevent long-term complications. While several risk factors have been established, the association between prematurity and DDH remains unclear. Our analysis sought to analyze the literature exploring the relationship between prematurity and DDH. Articles evaluating the relationship between prematurity and DDH published between 1 January 2000 and 1 February 2022 were queried, with 11 studies included for analysis. Overall, a total of 8720 patients were included. The gestational age ranged from 23 to 36 weeks for preterm and >= 37 weeks for term births. Seven studies agreed that gestational age did not have a significant impact on DDH. Pooled analysis of available data demonstrated no significant difference in DDH among preterm and term infants (OR, 1.11; 95% CI, 0.82-1.51; P = 0.49). Sub-group analysis of two studies reporting data on very preterm (<= 32 weeks) and term infants revealed no significant difference in the occurrence of DDH (OR, 4.58; 95% CI, 0.09-244.78; P = 0.45). Four studies found early gestational age is associated with a significantly higher incidence of mature hips compared to late preterm or term babies. Similarly, pooled analysis demonstrated significantly lower Graf classification among preterm infants (OR, 0.13; 95% CI, 0.03-0.61; P = 0.009). Based on the current literature, our analysis found that prematurity is not strongly associated with DDH. Furthermore, early gestational age was associated with a significantly higher incidence of mature hips measured by Graf classification.