Can the Entire Function of the Foot Be Concentrated in the Forefoot Area during the Running Stance Phase? A Finite Element Study of Different Shoe Soles

The goal of this study was to use the finite element (FE) method to compare and study the differences between bionic shoes (BS) and normal shoes (NS) forefoot strike patterns when running. In addition, we separated the forefoot area when forefoot running as a way to create a small and independent area of instability. An adult male of Chinese descent was recruited for this investigation (age: 26 years old; body height: 185 cm; body mass: 82 kg) (forefoot strike patterns). We analyzed forefoot running under two different conditions through FE analysis, and used bone stress distribution feature classification and recognition for further analysis. The metatarsal stress values in forefoot strike patterns with BS were less than with NS. Additionally, the bone stress classification of features and the recognition accuracy rate of metatarsal (MT) 2, MT3 and MT5 were higher than other foot bones in the first 5%, 10%, 20% and 50% of nodes. BS forefoot running helped reduce the probability of occurrence of metatarsal stress fractures. In addition, the findings further revealed that BS may have important implications for the prevention of hallux valgus, which may be more effective in adolescent children. Finally, this study presents a post-processing method for FE results, which is of great significance for further understanding and exploration of FE results.

The immediate effects of hallux valgus orthoses: A comparison of orthosis designs

BACKGROUND

Hallux valgus orthoses are available in a wide range of designs and materials, but the effects of their design on functional performance have not been fully investigated.

RESEARCH QUESTION

This present study aims to comprehensively analyze the immediate effects of soft and semi-rigid hallux valgus orthoses on balance, plantar pressure, hallux valgus angle, and subjective sensations.

METHODS

Sixteen female subjects have participated in the study, including 10 subjects with healthy feet and 6 with hallux valgus. Three conditions are tested, including in the barefoot and using two types of commercially available hallux valgus orthoses. The subjects participate in static and dynamic (walking) tests with the use of the Novel Pedar® system. The peak pressure values in the hallux, lateral toes, first metatarsophalangeal joint, 2-4th metatarsal heads, 5th metatarsal head, medial midfoot, lateral midfoot and rearfoot in the various foot conditions are examined and compared. The hallux valgus angle of each subject is measured based on their footprint. Their subjective feelings towards the orthoses are also evaluated. A repeated-measures analysis of variance, and independent-sample t-test are performed.

RESULTS

The correction of the hallux valgus angle is statistically significant when the subjects with hallux valgus use the orthoses. In comparing the two types of orthoses, the use of the orthosis made of soft materials results in correction in the hallux valgus angle and higher wear comfort, and lower plantar pressure in hallux area.

SIGNIFICANCE

The results provide insights into the design of hallux valgus orthoses, thus offering practical reference for the selection of hallux valgus orthosis with compromise between functional performance and wear comfort.

Bionic Footwear Effect to Lower Limb Locomotion in Biomechanical Analysis

Many scientific data have proven that regular wearing of high-heeled shoes adversely affects human health. Recent evidence suggested that bionic heels imitated hoofed animals have attracted widespread attention. However, few biomechanical studies have investigated the effects of bionic high-heeled footwear on the lower limbs. Accordingly, this study aimed to examine the impact of bionic high-heeled shoes (HHS) on the biomechanical characteristics of lower limbs by comparing kinematics and kinetics of walking in HHS and bionic flat-bottomed shoes (FBS). they find that when the subjects wore HHS, the loading is concentrated in the forefoot region for a much longer time. Couple with HHS lacks the cushioning effect of the complete sole, the sole has to rely only on plantar flexion and dorsiflexion of the ankle joint to cushion the impact force, which will undoubtedly increase the fatigue damage of the ankle joint. The unique split-toe structure balances the loading between the toes could reduce the risk of toes injury during walking. However, there are still risks of injury to the lower limbs of HHS, especially the ankle and knee joints.

Minimalist shoes running intervention can alter the plantar loading distribution and deformation of hallux valgus: A pilot study

BACKGROUND

Hallux valgus (HV) is one common deformity of the human foot. Metatarsal pain, gait deviation and foot function disorder may occur when HV is severe.

RESEARCH QUESTION

It was hypothesized that a 12-week minimalist shoes running intervention among mild and moderate hallux valgus males may alter foot morphology and plantar pressure distribution during walking and running.

METHODS

The foot morphology and plantar pressure data, in this study, were collected from eleven participants using the Easy-Foot-Scan (EFS) and Novel EMED force plate.

RESULTS

Compared to pre-intervention sessions, the hallux abductus angle and forefoot width decreased significantly with increased metatarsal waist girth in the post-intervention session. The peak pressure, maximum force and force time integral in the first metatarsal reduced significantly due to the distribution of plantar pressure to the central foot regions.

SIGNIFICANCE

The findings suggest that minimalist shoes may deform forefoot morphology and neutralize loading concentration for mild and moderate hallux valgus.

Lower limb mechanics during moderate high-heel jogging and running in different experienced wearers

The aim of this study is to investigate the differences in lower limb kinematics and kinetics between experienced (EW) and inexperienced (IEW) moderate high-heel wearers during jogging and running. Eleven experienced female wearers of moderate high-heel shoes and eleven matched controls participated in jogging and running tests. A Vicon motion analysis system was used to capture kinematic data and a Kistler force platform was used to collect ground reaction force (GRF). There were no significant differences in jogging and running speed respectively. Compared with IEW, EW adopted larger stride length (SL) with lower stride frequency (SF) at each corresponding speed. During running, EW enlarged SL significantly while IEW increased both SL and SF significantly. Kinematic data showed that IEW had generally larger joint range of motion (ROM) and peak angles during stance phase. Speed effect was not obvious within IEW. EW exhibited a significantly increased maximal vertical GRF (Fz2) and vertical average loading rate (VALR) during running, which was potentially caused by overlong stride. These suggest that both EW and IEW are at high risk of joint injuries when running on moderate high heels. For wearers who have to do some running on moderate high heels, it is crucial to control joint stability and balance SL and SF consciously.

Foot loading characteristics of Chinese bound feet women: a comparative analysis

The custom of bound feet among Chinese women has existed for almost a century. This practice has influenced the daily life of Chinese women, especially during everyday locomotion. The primary aim of this study is to analyze the loading patterns of bound feet. Specifically, the plantar pressure and center of pressure were analyzed for peak pressure, contact area, force time integral, center of pressure displacement velocity and trajectory in the anterior-posterior direction via a comparison with normal feet. The key outcomes from this work were that the forefoot and rearfoot of bound feet bear the whole loading during stance phase. The center of pressure displacement velocity of bound feet was also greatly reduced with the shortening of trajectories. This suggests that the proprioceptive system adjusts motor function to adapt to new loading patterns while maintaining locomotive stability. A biomechanical understanding of bound feet may assist with prevention, treatment and rehabilitation of bound feet disorders.