Samenvatting

Purpose The aim of this study is to describe the effect of slower walking speed on the ankle kinematics of typically developing children.
Method Three dimensional lower extremity joint kinematics were collected of 10 developing children (ages 6-9) walking at a comfortable walking speed (CWS) and slower walking speed (SLOW (CWS- 30% (±5%))) with infrared cameras (Vicon, Oxford, UK). Data from the infrared cameras was analyzed with Vicon Nexus 2.2 and BodyMech® software. Maximal plantar ankle flexion, maximal dorsal ankle flexion, instance of maximal dorsal flexion, instance of maximal plantar flexion and the duration of stance phase were the outcome measures.
Results The data showed that children reached significantly more dorsiflexion during the SLOW condition when compared to the CWS condition. The relative instance of maximum dorsal flexion angle took place earlier at the CWS condition than at the SLOW condition. The maximal plantar flexion and related time point were not significant different compared to the CWS condition. However, the duration of the stance phase did have a significant difference at the SLOW compared to CWS, the duration of the stance phase was significant longer at SLOW.
Conclusion The maximal dorsal flexion angle increased during a slower walking speed. The relative instance of maximal dorsal flexion angle occurred later during a slower walking speed. The maximal plantar flexion and the relative instance of the maximal plantar flexion angle were not significant different during a slower walking speed. The results indicate that the differences between conditions CWS and SLOW are small, but should be taken into account interpreting of clinical gait analysis data.