The Impact of Spinal Fusion on Hip Displacement in Cerebral Palsy

Abstract

Background and study aimsThe aims of this study were to determine the risk of progressive hip subluxation in children with CP after spinal fusion for scoliosis and how frequent the hips follow-up should be scheduled. Patients and methodsPelvis radiography [migration index (MI) and pelvic obliquity (PO)] of Gross Motor Function Classification System (GMFCS) levels IV and V children with CP who received spinal fusion and pelvic fixation were reviewed retrospectively. This population was categorized into three groups based on the MI at spinal fusion: G1 = 0-29%; G2 = 30-59%; and G3 = 60-100%. Results Fifty children (age 7.5-15.0 years) and categorized into 3 groups (G1 = 19, G2 = 23, G3 = 8; 100 hips in total). Preoperative and last follow-up MI were 22 ± 7% and 30 ± 20% (G1), 41 ± 9% and 43 ± 22% (G2), 92 ± 15% and 97 ± 10% (G3). The MIs at spinal fusion between groups were statistically different (p < 0.001). In G1, the mean MI progression was 5% and 25% at 12 months and 62 months, respectively. In G2, the mean MI progression was 9% and 25% at 12 months and 32 months, respectively. The progression more than 10% occurred within 2 years in G1 and within 1 year in G2. There was no difference between groups based on preoperative degree of PO (p = 0.653) and correction rate in PO (p = 0.421). Conclusions In GMFCS IV and V children with the highest risk for progression occurred with increasing preoperative MI, especially over 50%. Hips should be monitored continuously after spinal fusion until hip stability is documented.

Hip Surveillance and Management of Hip Displacement in Children with Cerebral Palsy: Clinical and Ethical Dilemmas

“…The group of children with CP who are most at risk of developing hip displacement/dislocation in the first decade of life are also the children who are most at risk of developing scoliosis in the second decade of life [ 70 , 71 ]. The careful work done through hip surveillance and by the hip reconstruction surgeon can be undone by the sudden development of scoliosis and pelvic obliquity [ 70 , 71 , 72 , 73 , 74 ]. Surgery to correct scoliosis usually involves instrumentation and arthrodesis of the spine from T2 to the pelvis [ 70 ].…”

Hip Displacement Does Not Change After Pelvic Obliquity Correction During Spinal Fusion in Children With Cerebral Palsy

“…Therefore, for most children, the timing of hip reconstruction typically occurs before the need for PSF 1. However, occasionally, the progression of these pathologies, and the need for treatment decisions, are concurrent 2. The question as to whether the hip or spine should be addressed first in CP remains controversial, with the majority of evidence being “expert opinion.”3…”

“…1 However, occasionally, the progression of these pathologies, and the need for treatment decisions, are concurrent. 2 The question as to whether the hip or spine should be addressed first in CP remains controversial, with the majority of evidence being "expert opinion." 3 The arguments for performing hip reconstructionsoft-tissue releases and osteotomies-before scoliosis correction are 3-fold.…”