Redesign and ergonomic assessment of a chest-support baby walker

Article type: Research Article

Authors: Golmohammadpour, Hamedeh^a | Garosi, Ehsan^{b; *} | Taheri, Mostafa^c | Dehghan, Naser^d | Ezbarami, Sahebeh Mirzaei^e | Karanikas, Nektarios^f

Affiliations: [a] Department of Industrial and System Engineering, The State University of New York at Buffalo, Getzville, NY, USA | [b] Department of Ergonomics, School of Public Health, Iran University of Medical Sciences, Tehran, Iran | [c] Department of Architecture, Faculty of Arts and Architecture, Science and Research Branch, Islamic Azad University, Tehran, Iran | [d] Ambient Intelligence Laboratory (AMI-Lab), Computer Science Department, Faculty of Science, University of Sherbrooke, Sherbrooke, QC, Canada | [e] Department of Biomechanics, Science and Research Branch, Islamic Azad University, Tehran, Iran | [f] School of Public Health and Social Work, Queensland University of Technology, Brisbane, QLD, Australia

Correspondence: [*] Address for correspondence: Ehsan Garosi, Department of Ergonomics, School of Public Health, Iran University of Medical Sciences, Teheran, Iran. E-mail: [email protected].

Abstract: BACKGROUND:Parents often use baby walkers (BWs) as assistive devices to improve their infants’ independent movement and motor skill acquisition. However, the literature suggests that conventional baby walkers (CBW) may cause delays in an infant’s ability to walk independently and musculoskeletal burden on parents. OBJECTIVE:In the current study, a baby walker (RBW) with chest support was redesigned and ergonomically assessed during an infant-walking task. METHODS:The anthropometric dimensions of 90 infants aged 7–11 months were measured in the city of Urmia, northwestern Iran. Following redesigning based on the results from expert panel meetings and prototyping of the RBW, 18 mothers (age: 28.33±4.27 and height: 163.75±5.32 and weight: 59.45±5.99) with their infants (9 boys and 9 girls) performed a simulated infant walking task in two experimental sessions using the CBW and RBW over a repeated measurements design. The infants’ feet track patterns, including the number of steps and step distances were assessed via the image analysis of the footprints. The mothers’ body posture and lower back spinal load were evaluated using Rapid Upper Limb Assessment (RULA) technique and 3D Static Strength Prediction Program (3DSSPP), respectively. RESULTS:Wilcoxon signed-rank tests showed infants walked more steps with the RBW (p = 0.002). Similarly, the distance between the infants’ left heel strike (p = 0.008) and their right and left toe-off (p = 0.03 and 0.02 respectively) was also significantly lower in the RBW use. Additionally, the body posture of mothers was improved (RULA final score from 7 for CBW to 5 for RBW). Moreover, lower back compression and shear forces were reduced significantly (p = 0.002) by the RBW use. CONCLUSION:According to the feet track pattern, infants took more balanced steps when the RBW was used. In addition, mothers were subjected to less pressure on the lumbar region when they placed and lifted their infant from the RBW. However, further work is necessary to investigate potential long-term effects of the RBWs use.

Keywords: Baby walker, infants, walking pattern, design, musculoskeletal disorders

DOI: 10.3233/WOR-220440

Journal: Work, vol. 76, no. 2, pp. 737-747, 2023