In developmental dysplasia of the hip (DDH), concentric reduction of dislocated hips
cannot be achieved by closed reduction in many cases, and open reduction is required
('failure of reduction'). The incidence of cases requiring open reduction and the
significance of risk factors for unsuccessful reduction remain unclear. We investigated
the overall rate and the risk factors for failed closed reduction in DDH.We followed
the Cochrane recommendations in our systematic review and meta-analysis. We performed
a systematic search in three medical databases to identify all studies reporting on
pediatric patients with hip dislocation in DDH on 2 July 2022. Eligible studies reported
on the rate of failure in children younger than 36 months. We calculated odds ratios
(ORs) with 95% CIs from two-by-two tables (event rate in risk group, event rate in
non-risk group).We identified 13 316 studies and included 62 studies (5281 hips) for
failure rate and 34 studies (3810 hips) for risk factor analysis. The overall rate
of failure in closed reduction was 20%. The risk of failure of reduction increased
with the grade of dislocation and was significantly higher for high dislocations (group
0-24: IHDI 4 vs IHDI 2 OR: 17.45, CI: 9.26-32.92; Tönnis 4 vs Tönnis 2 OR: 14.67,
CI: 1.21-177.37; Graf IV vs Graf III OR: 3.4, CI: 2.27-5.09). Male gender was also
a significant risk factor (OR: 2.27, CI: 1.13-4.56) in group 0-36.Higher grade dislocations
and male gender are significant risk factors for failure of reduction in closed reduction
in hip dislocation in DDH.
