Improved Myelination following Camp Leg Power, a Selective Motor Control Intervention for Children with Spastic Bilateral Cerebral Palsy: A Diffusion Tensor MRI Study

Abstract

Background and purpose: Children with spastic cerebral palsy have motor deficits associated with periventricular leukomalacia indicating WM damage to the corticospinal tracts. We investigated whether practice of skilled lower extremity selective motor control movements would elicit neuroplasticity.

Materials and methods: Twelve children with spastic bilateral cerebral palsy and periventricular leukomalacia born preterm (mean age, 11.5 years; age range, 7.3-16.6 years) participated in a lower extremity selective motor control intervention, Camp Leg Power. Activities promoted isolated joint movement including isokinetic knee exercises, ankle-controlled gaming, gait training, and sensorimotor activities (3 hours/day, 15 sessions, 1 month). DWI scans were collected pre- and postintervention. Tract-Based Spatial Statistics was used to analyze changes in fractional anisotropy, radial diffusivity, axial diffusivity, and mean diffusivity.

Results: Significantly reduced radial diffusivity (P < . 05) was found within corticospinal tract ROIs, including 28.4% of the left and 3.6% of the right posterior limb of the internal capsule and 14.1% of the left superior corona radiata. Reduced mean diffusivity was found within the same ROIs (13.3%, 11.6%, and 6.6%, respectively). Additionally, decreased radial diffusivity was observed in the left primary motor cortex. Additional WM tracts had decreased radial diffusivity and mean diffusivity, including the anterior limb of the internal capsule, external capsule, anterior corona radiata, and corpus callosum body and genu.

Conclusions: Myelination of the corticospinal tracts improved following Camp Leg Power. Neighboring WM changes suggest recruitment of additional tracts involved in regulating neuroplasticity of the motor regions. Intensive practice of skilled lower extremity selective motor control movements promotes neuroplasticity in children with spastic bilateral cerebral palsy.

FIG 1.

Flowchart detailing the recruitment and screening process leading to the total number of participants included in the study.

FIG 2.

TBSS results show significant reductions in RD and MD (P < . 05) after lower extremity SMC intervention. Coronal slices were selected at the level of the CSTs. From left to right, axial slices were selected at the level of the primary motor cortex, PLIC, and CerPed, respectively. Mid-sagittal slices were selected at the level of the CC. A, The WM skeleton is shown in green with additional arrows labeling the somatosensory cortex, ALIC, ACR, and EC. In the coronal view, ROIs for the SCR (red), PLIC (yellow), CerPed (blue), and sub-CerPed (orange) are shown. Significant pre- and postdifferences for the CP group (P < . 05) are shown for RD (B) and MD (C). The colormap (blue-light blue) denotes a significant decrease in the DTI measure (P < .05). A indicates anterior; FWE, family-wise error; I, inferior; L, left; P, posterior; R, right; S, superior.