Timely Hip Surgery Access in Children With Cerebral Palsy: Unaffected by Social Disadvantage at a Large Urban Safety Net Hospital
Authors: Wimmer Sam P. , Bent Melissa A. , Wren Tishya A. L. , Kay Robert M. 
Published: October 2024

Background:
Socioeconomic disadvantage has been shown to limit timely access to pediatric orthopaedic care and can result in poor surgical outcomes. Insurance coverage has often served as a proxy for socioeconomic status; however, area deprivation index (ADI) and child opportunity index (COI) are more comprehensive measures of social determinants of health (SDOH). The treatment of hip displacement in children with cerebral palsy (CP) requires early radiographic identification and continuous surveillance, which may be impacted by SDOH. This study seeks to evaluate the influence of insurance, ADI, and COI on preoperative Reimer migration percentage and need for pelvic osteotomy during varus derotation osteotomy (VDRO) in children with CP.

Methods:
This retrospective cohort study examined 219 patients with CP who underwent VDRO surgery for hip subluxation or dislocation at a tertiary referral center (135 male, mean age 7.9 y, SD: 2.9, range: 2.4 to 17.2; 17 GMFCS II, 21 GMFCS III, 89 GMFCS IV, 92 GMFCS V) from 2004 to 2022. Imaging and clinical documentation for patients with CP and hip displacement, age <18 years with ≥1 year of follow-up, treated with VDRO were reviewed. GMFCS level, preoperative Reimer migration percentages (MP), surgical details, and demographic and socioeconomic data were collected, and addresses were used to determine ADI (2018 version) and COI (2.0 database). The relationship of ADI, COI, and insurance type to preoperative Reimer MP of the more displaced hip and the need for pelvic osteotomy were analyzed with linear regressions and logistic regressions.

Results:
The mean preoperative Reimer MP was 64.4% (SD: 25.0, range: 0 to 100). As expected, patients functioning at higher GMFCS levels presented with greater Reimer MPs. The average Reimer MP was 34.0 for GMFCS II, 44.2 for GMFCS III, 64.6 for GMFCS IV, and 74.5 for GMFCS V (P<0.01). The mean ADI state decile (1 to 10 scale) and COI (1 to 100 scale) for the cohort were 5.6 (SD: 2.2, range: 1 to 10) and 37.2 (SD: 28.1, range: 4 to 100), respectively. ADI (P=0.77), COI (P=0.30), and insurance type (P=0.78) were not related to preoperative Reimer MP. However, patients with lower ADIs (OR 0.83, 95% CI [0.70, 0.99], P=0.04) and higher COIs (OR 1.01, 95% CI [1.00, 1.03], P=0.03) underwent pelvic osteotomies at a higher rate.

Conclusions:
ADI, COI, and insurance type were not related to preoperative Reimer MP. Interestingly, greater social disadvantage was associated with a lower frequency of pelvic osteotomy at the time of VDRO. Our data demonstrate that at our institution, greater social disadvantage does not result in limited access to timely orthopaedic care for children with CP. This is likely due to adequate governmental insurance coverage for children with neuromuscular disorders in this state and the active involvement of pediatric orthopaedic surgeons in government-sponsored clinics, including ongoing hip screening programs for children with CP. These results provide hope that healthcare disparities can potentially be mitigated.