Exploring Hand Dexterity in Spoon Handling : Impact of Handle Cross-Section on Dynamic Tripod Grip

Abstract

Spoons are among the fine tools frequently used by toddlers who transition from early power grips to refined dynamic tripod grips. Research on fine finger manipulations reveals that such operations are more stable when performed with relatively small finger flexion and pressure changes. Existing literature on pencil and chopstick handling shows that the cross-section of the handle affects fine manipulation, but there is limited research specifically evaluating such effects with regard to spoons. To design a spoon suitable for dynamic tripod grips and facilitate learning for toddlers with less mature manipulative skills, experiments were conducted with adults who exhibit stable dynamic tripod operations. This study synthesized spoon operation literature and movement processes to identify three specific tasks: Scooping, Cutting, Gathering. Following an analysis of commercially available products, six common cross-sectional shapes were selected. Thirty adults with normal hand function participated in the experiment, wearing flexion and pressure sensors to assess the impact of handle cross-section shapes on operational efficiency, finger stability, and finger pressure. Results indicate that hexagonal and pentagonal shapes offer the best operational efficiency. No significant differences in finger stability were observed among the six shapes, and circular shapes allowed for better performances in finger pressure. Overall, the combined evaluation suggests that circular, pentagonal, and hexagonal shapes are preferable, providing a foundation for product development in this field. The applicability of these findings to toddlers can be further validated through future experiments.

Keywords: Cross-section of a spoon handle, Dynamic tripod grip and manipulation, Spoon manipulation

DOI: 10.54941/ahfe1005691