Asymmetry of activation of lateral abdominal muscles during the neurodevelopmental traction technique.

OBJECTIVE: The aim of the study was to evaluate the symmetry and pattern of activation of lateral abdominal muscles (LAM) in response to neurodevelopmental traction technique. DESIGN AND PARTICIPANTS: Measurements of LAM thickness were performed in four experimental conditions: during traction with the force of 5% body weight (5% traction): 1) in neutral position, 2) in 20° posterior trunk inclination; during traction with the force of 15% body weight (15% traction): 3) in neutral position, 4) in 20° posterior trunk inclination. Thirty-seven healthy children participated in the study. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: To evaluate LAM activation level ultrasound technology was employed (two Mindray DP660 devices (Mindray, Shenzhen, China) with 75L38EA linear probes). An experiment with repeated measurements of the dependent variables was conducted. RESULTS: Side-to-side LAM activation asymmetry showed relatively high magnitude, however, significant difference was found only in case of the obliquus externus (OE) during stronger traction (P < 0.05). The magnitude of LAM thickness change formed a gradient, with the most profound transversus abdominis (TrA) showing the smallest change, and the most superficial OE - the greatest. The inter-muscle differences were most pronounced between the OE and TrA (P < 0.001). CONCLUSIONS: During the neurodevelopmental traction technique there is a difference in individual LAM activation level, with deeper muscles showing less intense activation. In statistical terms, the only signs of side-to-side asymmetry of LAM activation are visible in case of the OE, however, the magnitude of asymmetry is relatively high. The results allow to identify patterns of activation of LAM in children showing typical development that will serve as a reference in future studies in children with neurological disorder.

The impact of the neurodevelopmental traction technique on activation of lateral abdominal muscles in children aged 11-13 years.

BACKGROUND: The aim of the study was to evaluate the activation of lateral abdominal muscles (LAM) in response to neurodevelopmental traction technique as assessed by ultrasounds as well as to compare the effects of different traction forces. OBJECTIVE: An experiment with repeated measurements of the dependent variables was conducted. Thirty-seven children (22 girls) participated. METHODS: Measurements of LAM thickness (indicating LAM activation) were performed bilaterally during traction of 5% body weight: 1) in neutral position, 2) in 20° posterior trunk inclination; during traction of 15% body weight: 3) in neutral position, 4) in 20° posterior trunk inclination. The ultrasound technology was employed. RESULTS: When applying the lighter traction the superficial LAM (external and internal oblique muscles) showed significant changes. The mean thickness of both muscles during traction increased (both p < 0.001). The deepest transversus abdominis showed no response (p > 0.05). Stronger traction elicited smaller changes. External and internal oblique muscles showed significant increases (p < 0.001, p < 0.01, respectively). Transversus abdominis became less thick during stronger traction (p < 0.01). CONCUSIONS: The neurodevelopmental traction technique elicits the changes in LAM thickness in children with typical development. The superficial LAM show more distinct responses than the profound LAM. Stronger traction induces smaller LAM thickness changes than lighter traction.