Stimulating the motor development of very premature infants: effects of early crawling training on a mini-skateboard

Abstract

Aim: To examine the effects of an early home-based 8-week crawling intervention performed by trained therapists on the motor and general development of very premature infants during the first year of life.

Methods: At term-equivalent age, immediately following discharge from the Neonatal Intensive Care Unit (NICU), we randomly allocated 44 premature infants born before 32 weeks' gestation without major brain damage to one of three conditions in our intervention study: crawling on a mini-skateboard, the Crawliskate (Crawli), prone positioning control (Mattress), or standard care (Control). The Crawli and Mattress groups received 5 min daily at-home training administered by trained therapists for 8 consecutive weeks upon discharge from the NICU. The outcomes of greatest interest included gross motor development (Bayley-III) at 2, 6, 9, and 12 months (primary outcome) corrected age (CA), mature crawling at 9 months CA and general development at 9 and 12 months CA [Ages and Stages Questionnaires-3 (ASQ-3)]. The study was registered at www.clinicaltrials.gov; registration number: NCT05278286.

Results: A 3 (Condition) × 4 (Age) repeated measures ANOVA revealed that Crawli group infants had significantly higher Bayley-III gross motor development scores than Mattress and Control group infants. Crawli group infants also scored significantly higher on groups of Bayley-III items related to specific motor skills than infants in the other groups, including crawling at 9 months CA. We found significant differences in favor of the Crawli group in separate one-way ANOVAs at each of the ages we examined. A 3 (Condition) × 2 (Age) repeated measures ANOVA revealed that the Crawli group scored significantly higher than the Control group for the ASQ-3 total score and communication score and significantly higher for the fine motor score than the Control and Mattress groups. We found additional significant differences in favor of the Crawli group for other dimensions of the ASQ-3 in separate one-way ANOVAs at 9 and 12 months CA.

Interpretation: Early crawling training on a Crawliskate provides an effective way to promote motor and general development in very premature infants. The findings also provide clear evidence for a link between newborn crawling and more mature crawling later in development.

Keywords: cerebral palsy; crawliskate; early intervention; locomotion; neonate; newborn.

Figure 1

(A) A 2-day-old newborn resting on its belly and wrapped on the Crawli; (B) stimulation of quadrupedal propulsion on the Crawli; (C) 3D reconstruction of quadrupedal crawling on the Crawli; (D) structure of the Crawli. Patent: Barbu-Roth, M., Forma, V., Teulier, C., Anderson, D., Provasi, J., & Schaal, B. (2016). -Device for assisting the crawling of an infant. Patent WO2016009022. https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2016009022.

Figure 2

(A) photo of the beginning of a Crawli training session at home with the osteopath assisting placement of the feet of the infant on the mat. (B) Photo of a Mattress training session at home.

Figure 3

Premalocom first year follow-up.

Figure 4

Flow chart CONSORT.

Figure 5

Comparison of ATNAT scores between groups at each age. The number of subjects is displayed at the bottom of each histogram. A score of 2 (on the y-axis) is considered as an optimal ATNAT score. Ages are in corrected age. Significant differences are indicated by * for p < .05 and ns indicates a non-significant difference.

Figure 6

(A) mean distance covered per session by each subject in each group (orange = mattress group; blue = Crawli group) during his/her entire training. The distance covered (in cm) is represented on the y-axis and the subjects are distributed on the x-axis. The *** indicates a p-value <0.001. (B) Graphical representation of the mean distance (and SD) covered during each of the eight weeks of training for the Crawli group.

Figure 7

Gross motor scaled score. The boxes and whiskers represent the 10th, 25th, 75th and 90th percentiles with the mean represented by a circle and the median by a square. Significant differences are indicated with * for p < 0.05; ** for p < 0.01; *** for p < 0.001; p-values between 0.05 and 0.1 are reported in superscript.

Figure 8

Graphical representation of raw scores of grouped items of the Bayley scales reflecting major gross motor skills. Statistical analyses were done using Kruskal-Wallis tests. Significant differences and trends are shown in bold: * for p < 0.05; ** for p < 0.01; *** for p < 0.001.