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The 'true' acetabular index in children with cerebral palsy
1Orthopaedic Department, Guy's Hospital, Guy's & St Thomas' NHS Trust, London, UK.
Insights
The acetabular index is unreliable for guiding acetabuloplasty decisions in children with cerebral palsy. Clinical assessment during hip reconstruction surgery is recommended instead.
Area of Science:
- Pediatric Orthopedics
- Hip Dysplasia
- Cerebral Palsy
Background:
- The acetabular index is a radiographic measurement used to assess hip joint stability in children.
- It informs decisions regarding acetabular osteotomy during hip reconstruction surgery.
- Accurate measurement is crucial for appropriate surgical planning.
Purpose of the Study:
- To evaluate the utility of the acetabular index in predicting the need for acetabuloplasty in children undergoing hip reconstruction.
- To compare acetabular index measurements between children who underwent acetabuloplasty and those who did not.
- To assess the reliability of the acetabular index in children with cerebral palsy.
Main Methods:
- Retrospective analysis of pre- and postoperative acetabular index values.
- Comparison of measurements between two groups of children: those who had acetabuloplasty and those who did not.
- Decision for acetabuloplasty was based on hip congruity during open reduction.
Main Results:
- Pre-operative acetabular index measurements showed a mean difference of only 7 degrees between the two groups.
- The range of acetabular index measurements was similar in both groups.
- Difficulties in standardizing bony landmarks were noted in children with cerebral palsy.
Conclusions:
- The acetabular index is difficult to measure accurately and reliably in children with cerebral palsy due to standardized bony landmarks.
- Similar pre-operative values between groups suggest limited predictive value of the acetabular index for acetabuloplasty decisions.
- Abandoning routine acetabular index measurement before hip reconstruction in children with cerebral palsy is recommended, with decisions made intraoperatively.
Introduction:
The acetabular index is a measurement used to determine whether or not an acetabular osteotomy may be required at the time of hip reconstruction in children.
Methods:
A retrospective analysis of pre- and postoperative values of the acetabular index was carried out on two groups of children. One group of children had an acetabuloplasty and the other did not during hip reconstruction, the decision being made at the time of open reduction, based on lack of hip congruity.
Results:
When the pre-operative acetabular index measurements were reviewed, the mean difference between the two groups was only 7 degrees. Range of measurements was similar between the two groups.
Conclusions:
The acetabular index is difficult to measure in some children with cerebral palsy. The bony landmarks are difficult to standardise. This may explain the similar pre-operative values between the two groups of children in this study. We, therefore, recommend that before hip reconstruction in children with cerebral palsy, the measurement of the acetabular index should be abandoned. Decisions as to whether to undertake an acetabuloplasty or not should be made at the time of open reduction.