A follow-up analysis of the effects of manual reduction in 78 children with developmental dislocation of the hip

CHENG Zeng-hui; MA Rui-xue

doi:10.3969/j.issn.2095-252X.2013.08.003

Abstract： Objective To retrospectively study the morphological development of hip joints after manual reduction in children with developmental dislocation of the hip ( DDH ) under 18 months and from 18 to 36 months respectively, and to investigate the feasibility of manual reduction in children with DDH over 18 months. Methods 78 patients ( 97 hips ) under 36 months received adductor tenotomy, closed manual reduction, modified frog-position ( or frog-position ) plaster fixation and external device fixation in Children’s Hospital of Fudan University from January 2003 to December 2007. According to their ages when reduction, the patients were classified into 2 groups, under 18 months and older than or equal to 18 months ( from 18 to 36 months ) respectively. The morphological development of hip joints was observed in 6, 12, 24 and 36 months after manual reduction based on X-rays, including the acetabular index ( AI ), medial joint space ( MJS ), ossific nucleus ( ON ) of the femoral head, center-head distance discrepancy ( CHDD ) of the femoral head and Shenton’s line, together with the avascular necrosis ( AVN ) of the femoral head and residual acetabular dysplasia ( RAD ). The average duration of follow-up was 25.2 months ( range;6-60 months ). Results There were no statistically significant differences in the changes of AI, the decreasing degree of MJS, the developmental status of ON of the femoral head and the decreasing degree of CHDD after manual reduction between the 2 groups ( P=0.45, 0.57, 0.2, 0.1349, α=0.05 ). Shenton’s line became unstable after manual reduction in both groups, from discontinuousness before reduction, and then continuousness 6 months after the removal of support, to discontinuousness again when children began to walk, while the ratio of AVN of the femoral head was slightly lower in the group from 18 to 36 months ( P=0.04,α=0.05 ), and the ratio of RAD was higher than that of the group under 18 months ( P=0.01, α=0.05 ). Conclusions Closed manual reduction is still feasible in children with DDH over 18 months.