Alterations of treatment-naïve pelvis and thigh muscle morphology in children with cerebral palsy

Abstract

Lower limb (LL) muscle morphology and growth are altered in children with cerebral palsy (CP). Muscle alterations differ with age and with severity of motor impairment, classified according to the gross motor classification system (GMFCS). Muscle alterations differ also with orthopedic intervention, frequently performed at the level of the shank muscles since an early age, such as the gastrocnemius. The aim was to investigate the alterations of treatment-naïve pelvis and thigh muscle lengths and volumes in children with GMFCS levels I and II, of varying ages. 17 children with CP (GMFCS I: N = 9, II: N = 8, age: 11.7 ± 4 years), age-matched to 17 typically developing (TD) children, underwent MRI of the LL. Three-dimensional reconstructions of the muscles were performed bilaterally. Muscle volumes and lengths were calculated in 3D and compared between groups. Linear regression between muscle volumes and age were computed. Adductor-brevis and gracilis lengths, as well as rectus-femoris volume, were decreased in GMFCS I compared to TD (p < 0.05). Almost all the reconstructed muscle volumes and lengths were found to be altered in GMFCS II compared to TD and GMFCS I. All muscle volumes showed significant increase with age in TD and GMFCS I (R 2 range: 0.3-0.9, p < 0.05). Rectus-femoris, hamstrings and adductor-longus showed reduced increase in the muscle volume with age in GMFCS II when compared to TD and GMFCS I. Alterations of treatment-naïve pelvis and thigh muscle volumes and lengths, as well as muscle growth, seem to increase with the severity of motor impairment in ambulant children with CP.

Measuring skeletal muscle morphology and architecture with imaging modalities in children with cerebral palsy: a scoping review

“…Study sample size ranged from 1 to 50 participants with CP, with the median sample size being 15, and total age range of 0 to 23 years. The majority of the studies reported a mean age of the participants to be between 8 and 13 years ( n =55) 28–82 . Fifteen studies included participants who were under the age of 4 years 29,30,68,78,83–93 .…”

“…Twenty‐three studies included participants whose age range varied by 10 years or more (e.g. 6–17y) 29–34,36,41,45,50,59,61,63,68,69,73,77,81,85,92,94–96 . Studies most frequently investigated children with CP in Gross Motor Function Classification System (GMFCS) levels I and II (GMFCS level I=62, 29,31,33,34,36–39,41–47,49,50,53–59,61–63,66–71,73–79,81–86,88,89,91–104 GMFCS level II=65, 29–31,33,34,36–39,41–47,49,50,53–59,61–63,65–71,73–79,81–86,88,89,91–105 GMFCS level III=29, 30–34,37–39,52,55,56,62,67,68,73,83–86,91–96,100–102,105 GMFCS level IV=14,…”

“…Muscle variable data were presented either as the raw output or normalized. Normalization methods for muscle volume include being divided by: body mass ( n =14) 49,50,53,54,58,72,73,81,87–89,94,95,98 bone length ( n =5), 75–78,105 or by a product of height multiplied by body mass ( n =3) 56,59,97 . Normalization of fascicle length data were by bone length ( n =10), 28,30,37,40,42,47,60,66,87,105 or the participant's height 37 .…”

“…Forty‐six studies 31–34,36,38,39,41–44,47,49–55,57,59,62–71,73–78,83,85,86,90–92,95,105,106 included additional measures to the variable(s) of muscle. The majority of these 46 studies ( n =39) 31,33,34,36,38,39,41–44,47,49–51,53–55,59,62–66,68–71,74–77,83,85,86,90–92,95,105 included measures that fall under the Body Structures and Function domain of the ICF, with measures of spasticity ( n =20 studies), 31,36,42,49,50,53,54,59,65,66,68–70,75,76,85,86,91,92,95 muscle strength ( n =19 studies), 34,36,38,42,44,49–51,55,59,62,64,65,69,70,74,76,77,83 ROM ( n =15 studies), 31,33,36,39,41,42,44,49,50,59,66,70,71,90,105 and gait ( n =10 studies) 36,38,42,43,47,50,63,65,66,69 the most common. Twenty‐four studies 31,32,34,38,42,52,57,62–69,73,75,76,78,83,85,86,95,106 included measures within the Activity domain of the ICF, mostly the Gross Motor Function Measure (GMFM)‐66/88, 31,65,67–69,83,85,86,95 or other measures relating to mobility,…”

“…6-17y). [29][30][31][32][33][34]36,41,45,50,59,61,63,68,69,73,77,81,85,92,[94][95][96] Studies most frequently investigated children with CP in Gross Motor Function Classification System (GMFCS) levels I and II (GMFCS level I=62, 29,31,33,34,[36][37][38][39][41][42][43][44][45][46][47]49,50,[53][54][55][56][57][58][59][61][62][63][66][67]…”