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Progression of Hip Displacement during Radiographic Surveillance in Patients with Cerebral Palsy
Jae Young Park1, Young Choi2, Byung Chae Cho3
1Department of Orthopaedic Surgery, 21th Century Hospital, Wonju, Korea .
Insights
Hip displacement progresses in children with cerebral palsy (CP), particularly those with higher Gross Motor Function Classification System (GMFCS) levels. Regular radiographic hip surveillance is crucial for monitoring and predicting this progression.
Area of Science:
- Orthopedics
- Pediatric Neurology
- Radiology
Background:
- Hip displacement is a common complication in children with cerebral palsy (CP).
- The rate of hip displacement progression varies significantly based on the severity of motor impairment.
Purpose of the Study:
- To investigate the annual rate of hip displacement progression in patients with CP.
- To analyze radiographic changes according to Gross Motor Function Classification System (GMFCS) levels during hip surveillance.
Main Methods:
- Retrospective analysis of serial hip radiographs from 197 CP patients (<20 years) with at least 6-month intervals.
- Radiographic indices including migration percentage (MP), neck-shaft angle (NSA), acetabular index (AI), and pelvic obliquity (PO) were measured.
- Annual changes were analyzed and adjusted for factors like sex, laterality, and CP type across GMFCS levels.
Main Results:
- Significant annual increases in MP were observed across all GMFCS levels: 0.3%/year (I-III), 1.9%/year (IV), and 6.2%/year (V).
- Patients with GMFCS level IV showed a significant annual increase in NSA of 3.4°.
- Progression was most rapid in patients with GMFCS level V.
Conclusions:
- Periodic radiographic hip surveillance is essential for patients with CP, especially those classified as GMFCS level IV or V.
- These findings enable physicians to predict and inform families about the potential progression of hip displacement.
- Early detection and monitoring can guide management strategies for hip instability in CP.
Abstract:
Progression of hip displacement is common in patients with cerebral palsy (CP). We aimed to investigate the rate of progression of hip displacement in patients with CP by assessing changes in radiographic indices according to Gross Motor Function Classification System (GMFCS) level during hip surveillance. We analyzed the medical records of patients with CP aged < 20 years who underwent at least 6 months interval of serial hip radiographs before any surgical hip intervention, including reconstructive surgery. After panel consensus and reliability testing, radiographic measurements of migration percentage (MP), neck-shaft angle (NSA), acetabular index (AI), and pelvic obliquity (PO) were obtained during hip surveillance. For each GMFCS level, annual changes in radiographic indices were analyzed and adjusted for affecting factors, such as sex, laterality, and type of CP. A total of 197 patients were included in this study, and 1,097 radiographs were evaluated. GMFCS classifications were as follows: 100 patients were level I-III, 48 were level IV, and 49 were level V. MP increased significantly over the duration of hip surveillance in patients with GMFCS levels I-III, IV, and V by 0.3%/year (P < 0.001), 1.9%/year (P < 0.001), and 6.2%/year (P < 0.001), respectively. In patients with GMFCS level IV, NSA increased significantly by 3.4°/year (P < 0.001). Our results suggest that periodic monitoring and radiographic hip surveillance is warranted for patients with CP, especially those with GMFCS level IV or V. Furthermore, physicians can predict and inform parents or caregivers regarding the progression of hip displacement in patients with CP.
