Julia Looper, PT, PhD
Title: ARM POSITIONING AND WALKING STYLE OF CHILDREN DURING FIRST 5 MONTHS OF
Authors: Poole, Lauren; Brett, Katrina; Gunselman, Alison; Schrempf, Bernadette; Looper, Julia
Affiliation: Physical Therapy, University of Puget Sound, Tacoma, WA, United States.
Purpose: Arm position during initial independent walking (IW) affects upper trunk biomechanics with gait. Arm positioning plays a role in forward propulsion and in maintaining upright position. Previous research has not established time lines or percentages of time spent in each arm position as IW progresses in typically developing infants. This study describes arm positioning across the initial 5 months of IW in typically developing infants. We hypothesized that high to middle guard positioning would be dominant during early visits with a progression to low guard by later visits. We did not expect to see consistent flexed arm movement or reciprocal arm swing within this time period.
Subjects : Eight typically-developing children (5 M, 3 F).
Materials/Methods : In this secondary analysis, researchers evaluated and coded video from trials at 1–5 months of IW. Researchers coded three trials per visit using arm positioning descriptions adapted from Ledebt (2000), including reciprocal arm swing (RAS), flexed movement (FM), high guard(HG), middle guard(MG), and low guard (LG). Time in each arm position for each arm in seconds is the dependent variable. Researchers performed descriptive statistics on the dependent variable for each visit. Other statistics performed include a 2(hand)x5(visit) ANOVA with repeated measures and post hoc analysis with Bonferonni correction.
Results : The mean percentage of time in each arm position during the first visit was 2.6% RAS, 6.3% FM, 20.7% LG, 52.2% MG, and 18.5% HG. During the fifth visit, the mean percentages were 10.7% RAS, 76.4% FM, 8.1% LG, 3.5% MG, and 1.7% HG. For the fifth visit, the means were 1.7% high guard, 3.5% middle guard, 8.1% low guard, 76.4% flex movement, and 10.7% reciprocal arm swing. A 5 (visits) x 2 (sides) ANOVA with repeated measures revealed a left-to-right difference for HG (p=.035) as well as a significant side-by-visit interaction for HG (p=.023) and MG (p=.018). There was also a significant visit effect between visits 1 and 3 and between visits 1 and 5 for MG (p=.024, .003, respectively) and FM (p=.015, .005, respectively) with a trend toward significance for low guard (p=.055).
Conclusions : Infants demonstrate a transition from stable arm positions to more dynamic arm movement with more walking experience. Dynamic arm positioning development begins early in IW, and provides a foundation for the emergence of RAS and adult-like upper extremity mechanics during gait.
Clinical Relevance : This study describes changes in arm position over time – from stable upper extremity strategies to more mobile, exploration-facilitating strategies. Therapists should therefore monitor the transition from guarding to dynamic strategies during the first few months of IW for typically developing infants. If the transition does not occur, closer observation may be needed in order to facilitate early intervention.
KEYWORDS: High Guard, Middle Guard, Low Guard, Flexed Movement, Reciprocal Arm Swing, Gait, Arm Position.
University of Puget Sound
Schrempf, Bernadette; Looper, Julia PhD, PT; Poole, Lauren; Gunselman, Alison; and Brett, Katrina, "Arm Positioning and Walking Styles of Children During First 5 Months of Independent Walking" (2015). Physical Therapy Research Symposium. 12.