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Protective effect of modified lange "second position" for developing avascular necrosis following closed reduction
Ana Laura Arenas-Díaz1, Carlos A Guzmán-Martín2, Thania Ordaz-Robles2
1Medical Staff, Foot and Ankle and Cerebral Palsy Clinic, Shriners Hospital for Children, Av. Del Iman No. 257. Pedregal de Santa Úrsula, Coyoacán, 09820, Mexico. Ana_ArenasMD@outlook.com.
Insights
A modified Lange position cast after initial Human Position immobilization for hip dysplasia reduced avascular necrosis risk. This hip dysplasia treatment showed no significant difference in residual hip dysplasia or re-dislocation rates.
Area of Science:
- Pediatric Orthopedics
- Pediatric Surgery
- Developmental Biology
Background:
- Developmental Dysplasia of the Hip (DDH) is a common pediatric hip condition.
- Immobilization is crucial for hip concentricity post-reduction.
- Existing methods like the Human Position carry risks, including avascular necrosis (AVN).
Purpose of the Study:
- To evaluate the efficacy of closed reduction (CR) with two distinct immobilization techniques.
- To determine if specific immobilization strategies reduce complications like residual hip dysplasia (RHD), re-dislocation, and AVN.
Main Methods:
- A cohort of 66 patients (84 hips) with DDH underwent CR.
- Two immobilization techniques (Group A and Group B) were compared.
- Outcomes (RHD, re-dislocation, AVN) were assessed with a minimum 48-month follow-up.
Main Results:
- Group B, utilizing a modified Lange position, showed a significant protective effect against AVN (p=0.026).
- No statistically significant differences were observed between groups for RHD (p=0.563) or re-dislocation (p=0.909).
Conclusions:
- The modified Lange "second position" cast, following initial Human Position immobilization, offers a protective effect against AVN.
- This approach may reduce AVN development in children treated for DDH via CR.
- Immobilization strategy is key in managing DDH complications.
Background:
Developmental Dysplasia of the Hip (DDH) is a condition affecting hip joint development in children, presenting multiple manifestations. Immobilization methods to ensure hip concentricity, such as the human position and modified Lange position, vary in effectiveness and risks, especially avascular necrosis. The purpose of this study was to identify whether closed reduction (CR), with two different immobilization techniques, is effective in avoiding complications such as residual hip dysplasia (RHD), re-dislocation, and Avascular Necrosis (AVN).
Methods:
A total of 66 patients with DDH (84 hips) were treated with two different techniques of immobilization (groups A and B); the mean age at the time of reduction was 8 (6-13) months. The rates of RHD, Re-dislocation, and AVN were determined with a minimum follow-up of 48 months in both techniques.
Results:
The Chi-square analysis conducted across the study groups unveiled that patients in Group B demonstrated a protective effect against AVN compared to those in Group A (OR: 0.248, 95% CI: 0.072-0.847, p = 0.026). However, no statistically significant differences were found between the groups concerning RHD (p = 0.563) and re-dislocation (p = 0.909).
Conclusions:
After the initial Human Position immobilization, the second cast with the modified Lange "second position" demonstrated a protective effect compared with maintaining the Human Position immobilization throughout the immobilization period, reducing the likelihood of AVN development in patients undergoing closed reduction for developmental dysplasia of the hip.
