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Can Medialization of Acetabular Rim Be a Prognostic Factor in Treatment of Developmental Dysplasia of Hip?
Pınar Nercis Koşar1, Elif Ergün1, Dilek Gökharman1
1Department of Radiology, Ankara Training and Research Hospital, Ankara, Turkey.
Insights
Acetabular rim medialization (ARM) effectively predicts treatment success for Graf type III and IV hips. Combining ARM with treatment initiation time significantly improves prognostic accuracy for infant hip dysplasia.
Area of Science:
- Pediatric Orthopedics
- Developmental Dysplasia of the Hip
- Diagnostic Imaging
Background:
- Graf classification is standard for hip ultrasound in infants.
- Accurate prognosis is crucial for timely and effective treatment of developmental dysplasia of the hip (DDH).
- Current prognostic factors may not fully capture treatment outcomes for severe hip dysplasia.
Purpose of the Study:
- To evaluate acetabular rim medialization (ARM) as a novel parameter for treatment decisions in Graf type III and IV hips.
- To assess the prognostic value of ARM compared to initial diagnosis age.
- To determine if combining ARM and age improves prognostic accuracy.
Main Methods:
- Retrospective study of 35 hips (26 infants) with Graf type III/IV hips from 2015-2019.
- Measurement of ARM using a standardized technique on hip ultrasound.
- Analysis of treatment duration, outcomes, and correlation with ARM and age at diagnosis.
Main Results:
- ARM measurements varied between 4-9.5 mm in hips with poor prognosis.
- Both age at diagnosis (P=.04) and ARM (P=.00) significantly impacted treatment success.
- ARM demonstrated superior prognostic ability (AUC=0.95) compared to age (AUC=0.68).
- Combined ARM and age yielded the highest prognostic accuracy (AUC=0.98).
Conclusions:
- Acetabular rim medialization (ARM) shows significant potential as a prognostic factor for Graf type III and IV hips.
- ARM can guide treatment choice and duration, offering a more precise approach.
- The combination of ARM and treatment initiation time substantially enhances prognostic prediction in infant hip dysplasia.
Objectives:
To investigate if acetabular rim medialization (ARM) can be used as a new parameter in determining the treatment choice and duration in Graf type III and IV hips.
Methods:
Among the 12,300 infants who underwent hip ultrasound (US) according to Graf's method between 2015 and 2019, 26 infants (9 had bilateral pathology hence 35 hips) with type III and IV hips, whose follow-up data could be obtained were included in the study. Age of the infants at the initial diagnosis, ARM measurement, the duration of harness treatment, and the treatment results were noted. To determine the extent of ARM, distance between a line that is drawn tangential to the iliac wing and acetabular rim was measured.
Results:
In cases with poor prognosis, ARM measurement was 6 to 8.5 mm on the right hip and 4 to 9 mm on the left hip. Bilaterality or unilaterality, left or right pathology, and gender did not have a significant effect on the prognosis (P >.05). Age at the initial diagnosis and ARM had significant effects on treatment success (P = .04, P = .00, respectively). In predicting the prognosis, ARM was found to be more successful than age (AUC = 0.95 versus AUC = 0.68). When these two variables were evaluated together, the success in predicting the prognosis significantly increased (AUC = 0.98).
Conclusions:
ARM measurement may have an important role in determining the treatment method and duration in Graf type III and IV hips. It can be used as a prognostic factor alone or in combination with treatment initiation time. When the two factors are combined, prognostic value significantly increases.
