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Risk factors for re-dislocation after closed reduction in children with developmental dysplasia of the hip
Jingfang Xu1, Yi Yang1, Kai Yu1
11. Department of Pediatric Surgery, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, National Regional Medical Center for Children, Hangzhou 310052, China.
Insights
Identifying risk factors for re-dislocation after hip dysplasia treatment is crucial. High preoperative acetabular index, low flexion angle, and increased head-socket distance predict re-dislocation in children with developmental dysplasia of the hip (DDH).
Area of Science:
- Pediatric Orthopedics
- Developmental Dysplasia of the Hip (DDH)
- Hip Joint Biomechanics
Background:
- Developmental Dysplasia of the Hip (DDH) is a common pediatric condition requiring intervention.
- Closed reduction followed by plaster fixation is a primary treatment for DDH in infants.
- Re-dislocation after closed reduction can lead to further complications and treatment challenges.
Purpose of the Study:
- To identify key risk factors associated with re-dislocation after closed reduction in children diagnosed with DDH.
- To provide data that can help clinicians predict and potentially prevent post-reduction hip instability.
Main Methods:
- Retrospective analysis of clinical data from 88 children (103 hips) treated for DDH.
- Patients underwent adductor muscle relaxation, closed reduction, and plaster fixation.
- Univariate and multivariate logistic regression analyses were used to determine significant risk factors for re-dislocation.
Main Results:
- A re-dislocation rate of 21.2% was observed among the treated hips.
- Preoperative acetabular index (AI) > 40.5°, intraoperative hip flexion angle < 80.5°, and head-socket distance > 6.95 mm were identified as significant risk factors.
- The combination of these factors and the International Hip Dysplasia Institute (IHDI) grade demonstrated high predictive accuracy (AUC=0.91) for re-dislocation.
Conclusions:
- Preoperative acetabular index, intraoperative hip flexion angle, and head-socket distance are critical predictors of re-dislocation in DDH patients.
- Incorporating these quantitative measures with the IHDI grade can improve the prediction of postoperative re-dislocation.
- These findings can guide surgical decisions and post-treatment management to minimize re-dislocation rates.
Objective:
To investigate the risk factors for re-dislocation after the closed reduction in children with developmental dysplasia of the hip (DDH).
Methods:
The clinical data of 88 children aged ≤ 18 months with DDH (103 hips) who were treated with adductor muscle relaxation + closed reduction + plaster fixation at the Children's Hospital, Zhejiang University School of Medicine from January 2015 to December 2017, were retrospectively analyzed. According to the diagnostic criteria of hip dislocation, patients were divided into two groups: reduction group and re-dislocation group. The univariate and multivariate logistic regression analysis were applied to identify the risk factors for the re-dislocation of children.
Results:
Eighty-six patients (99 hips) successively underwent the treatment. 69 hips were fixed at the first intention, 9 hips at the second intention, and a total of 78 hips with no re-dislocation occurred till the last follow-up with a rate of 78.8%. The univariate analysis showed that preoperative acetabular index (AI), International Hip Dysplasia Institute (IHDI) grade, intraoperative hip flexion angle, and intraoperative head-socket spacing were significantly related to the occurrence of re-dislocation after closed-reduction. The multivariate logistic regression analysis showed that preoperative AI > 40.5° ( OR=5.57, P<0.01), flexion angle < 80.5° ( OR=4.93, P<0.01) and head-socket distance > 6.95 mm ( OR=8.42, P<0.01) were risk factors for the re-dislocation. The area under the receiver operator characteristic curve was 0.91 when preoperative AI > 40.5°, flexion angle < 80.5°, head-socket distance > 6.95 mm, and IHDI grade were used to predict the occurrence of re-dislocation, and the sensitivity and specificity were 0.72 and 0.87, respectively.
Conclusions:
Preoperative AI > 40.5°, intraoperative hip flexion angle < 80.5°, and head-socket distance > 6.95 mm are risk factors for postoperative re-dislocation in children with DDH. These risk factors combining with the IHDI grade would be better to predict the occurrence of re-dislocation.
