Energy consumption does not change after selective dorsal rhizotomy in children with spastic cerebral palsy

Abstract

Aim To determine whether energy consumption changes after selective dorsal rhizotomy (SDR) among children with cerebral palsy (CP). Method We retrospectively evaluated net nondimensional energy consumption during walking among 101 children with bilateral spastic CP who underwent SDR (59 males, 42 females; median age [5th centile, 95th centile] 5y 8mo [4y 2mo, 9y 4mo]) compared to a control group of children with CP who did not undergo SDR. The control group was matched by baseline age, spasticity, and energy consumption (56 males, 45 females; median age [5th centile, 95th centile] 5y 8mo [4y 1mo, 9y 6mo]). Outcomes were compared at baseline and follow‐up (SDR: mean [SD] 1y 7mo [6mo], control: 1y 8mo [8mo]). Results The SDR group had significantly greater decreases in spasticity compared to matched controls (–42% SDR vs –20% control, p<0.001). While both groups had a modest reduction in energy consumption between visits (–12% SDR, –7% control), there was no difference in change in energy consumption (p=0.11) or walking speed (p=0.56) between groups. Interpretation The SDR group did not exhibit greater reductions in energy consumption compared to controls. The SDR group had significantly greater spasticity reduction, suggesting that spasticity had minimal impact on energy consumption during walking in CP. These results support prior findings that spasticity and energy consumption decrease with age in CP. Identifying matched control groups is critical for outcomes research involving children with CP to account for developmental changes.

Long‐term effects of spasticity treatment, including selective dorsal rhizotomy, for individuals with cerebral palsy

“…We found that spasticity does not lead to elevated walking energy. This confirms earlier findings based on matched cohorts and contradicts a widely held view 33 . High energy consumption is a significant problem for individuals with CP; however, spasticity is not the cause.…”

Skeletal muscle maximal mitochondrial activity in ambulatory children with cerebral palsy

“…However, recent research shows that increased oxygen consumption (and associated increased energetics) during walking cannot be solely explained by the degree of inefficiency of gait patterns 10 or the presence of spasticity. 11 Furthermore, independently ambulatory children have stable GMFCS levels as they grow older 12,13 but continue to reduce their capacity for activity and participation in daily activities. 14 Peripheral muscle metabolic factors such as capillarization, mitochondrial content, and function 15,16 are also required for energetics of movement.…”

Causal Effects Contributing to Elevated Metabolic Power During Walking in Children Diagnosed with Cerebral Palsy

“…Six muscle groups were assessed bilaterally: hip flexors, hip adductors, rectus femoris, hamstrings, plantarflexors, and tibialis posterior. We calculated a summary spasticity score by applying polychoric principal component analysis to the bilateral measurements from these six muscles for individuals with complete data (Rozumalski and Schwartz, 2009; Zaino et al, 2020). We used polychoric principal component analysis since standard principal component analysis produces biased estimates with categorical data (Kolenikov and Angeles, 2009).…”

“…Spasticity is present in up to 91% of children with CP (Odding et al, 2006) and clinicians often believe it causes high metabolic power via inappropriate or prolonged muscle contraction and co-contraction of agonists and antagonists. However, several recent studies have indicated that spasticity reduction does not cause meaningful reductions in metabolic power during walking (Ubhi et al, 2000; Thomas et al, 2004; Bjornson et al, 2007; Munger et al, 2017; Zaino et al, 2020). Reduced metabolic power following spasticity treatment in observational settings likely arises from other factors such as aging.…”