Reliability of a multi-segment foot model in a neutral cushioning shoe during treadmill walking

The effects of the tension of figure-8 straps of a soft ankle orthosis on the ankle joint kinematics while walking in healthy young adults: A pilot study

BACKGROUND

Figure-8 straps are commonly used in ankle orthoses, which are provided to reduce the risks of primary and recurrent sprain by providing functional support. Functional treatment with ankle orthoses can provide better rehabilitation than immobilization for a mild ankle sprain. However, it is not known how much tension should be applied to the straps while donning the orthosis to optimize its effectiveness.

RESEARCH QUESTION

The aim of this study was to investigate the effects of figure-8 strap tension of a soft ankle orthosis on ankle joint kinematics in the sagittal, coronal, and transverse planes during gait in healthy young adults.

METHODS

Ten healthy adults (five males and five females) were enrolled in this study. The 3-dimensional motion analysis system was used to evaluate the ankle kinematics of the participants during gait under five conditions: no soft ankle orthosis, soft ankle orthosis with no figure-8 straps tension (lace-up only), 50 N, 80 N, and 110 N tension of the figure-8 straps, respectively. All participants walked in a straight path at a comfortable speed.

RESULTS

Plantarflexion angles were significantly reduced with 110 N of tension in the figure-8 straps when compared to the lace-up only and a moderate correlation with r = 0.34 (p = 0.03) was observed between the tensions of figure-8 straps and maximum plantarflexion angles at pre-swing of a gait cycle. No significant effects on ankle joint angles were demonstrated in the coronal and transverse planes.

SIGNIFICANCE

This study showed that increasing the tension of the figure-8 straps could restrict the ankle joint plantarflexion angle during pre-swing in gait. However, it might not affect inversion/eversion or internal/external rotation angles of the ankle joint in individuals without ankle pathologies.

Do different multi-segment foot models detect the same changes in kinematics when wearing foot orthoses?

Background

Different multi-segment foot models have been used to explore the effect of foot orthoses. Previous studies have compared the kinematic output of different multi-segment foot models, however, no study has explored if different multi-segment foot models detect similar kinematic changes when wearing a foot orthoses. The aim of this study was to compare the ability of two different multi-segment foot models to detect kinematic changes at the hindfoot and forefoot during the single and double support phases of gait when wearing a foot orthosis.

Methods

Foot kinematics were collected during walking from a sample of 32 individuals with and without a foot orthosis with a medial heel bar using an eight-camera motion capture system. The Oxford Foot Model (OFM) and a multi-segment foot model using the Calibrated Anatomical System Technique (CAST) were applied simultaneously. Vector field statistical analysis was used to explore the kinematic effects of a medial heel bar using the two models, and the ability of the models to detect any changes in kinematics was compared.

Results

For the hindfoot, both models showed very good agreement of the effect of the foot orthosis across all three anatomical planes during the single and double support phases. However, for the forefoot, the level of agreement between the models varied with both models showing good agreement of the effect in the coronal plane but poorer agreement in the transverse and sagittal planes.

Conclusions

This study showed that while consistency exists across both models for the hindfoot and forefoot in the coronal plane, the forefoot in the transverse and sagittal planes showed inconsistent responses to the foot orthoses. This should be considered when interpreting the efficacy of different interventions which aim to change foot biomechanics.

Effect of Long-Distance Running on Inter-segment Foot Kinematics and Ground Reaction Forces: A Preliminary Study

Long-distance running has gained massive popularity in recent years, yet the intra-foot adaptations during this event remain unclear. This study aimed to examine the kinematic and ground reaction force alterations induced within the foot following a 5 and 10 km run using the Oxford Foot Model Ten marathon-experienced recreational runners participated in this study. Five-kilometer running led to more rearfoot dorsiflexion, rearfoot eversion, and rearfoot rotation while less forefoot plantarflexion during the stance phase. Increased rearfoot plantarflexion, while decreased forefoot plantarflexion, supination, adduction, and hallux plantarflexion were observed at 10 km. In addition, the forefoot space of footwear was found to play a role in hallux kinematics. Concerning GRFs, only a lesser propulsive force was presented after a 10 km run. Findings of this study showed that 5 km of running would induce excessive foot motion while 10 km of running may gradually change the foot posture and lead to reduced propulsive forces, which could potentially increase the risks of running-related injuries (RRI) due to overuse or fatigue. Nevertheless, further research is warranted, and this study could be used as a preliminary reference to evaluate and predict foot running-related injuries.