Effects of Custom-mold Insole by Medial Heel Skive Technique on Physical Function in Flexible Flat Foot

Objectives: Flexible Flat Foot (FFF), a common foot deformity decreasing medial longitudinal arch height is often comorbid with subtalar joint pronation causing physical activity difficulties in this population. Among the orthotic insoles prescribed for improving foot function, foot orthoses with medial heel skive technique have a limited research background. The present study aimed to investigate the effects of the custom-mold insole with medial heel skive technique on physical function in FFF. Methods: Eighteen adults with FFF from the University of Social Welfare and Rehabilitation Sciences students and staff participated in this study. Custom-Mold insole with medial heel skive was fabricated for all research participants. Physical function in the activities of daily living and sports was assessed by the Foot and Ankle Ability Measure (FAAM), Activities of Daily Living (ADL) subscale (ADL-FAAM), and SPORT-FAAM questionnaires at the beginning of the study and 6 weeks after. Paired Samples t-test and nonparametric tests were used to compare the collected results. Results: After 6 weeks of using the insole with medial heel skive technique, scores in both ADL and SPORTS activities were significantly improved. Discussion: Foot function improvement was not found in all of the studies assessing foot function in flat feet after using different orthotic insoles, by different questionnaires or other systems. In this study, foot and ankle function was significantly improved per FAAM questionnaire- which had highly limited use in orthotic interventions in flat feet population- using medial heel skive technique; however, further studies are required to accentuate medial heel skive technique effect on flat feet function by comparing this technique with other positive cast modifications to control the flat foot. According to the present study results, custom-mold insole with medial heel skive may improve physical function in FFF and can be prescribed in this group.

Design and Preliminary Validation of Individual Customized Insole for Adults with Flexible Flatfeet Based on the Plantar Pressure Redistribution

Flatfoot is a common musculoskeletal deformity. One of the most effective treatments is to wear individually customized plantar pressure-based insoles to help users change the abnormally distributed pressure on the pelma. However, most previous studies were divided only into several plantar areas without detailed plantar characteristic analysis. In this study, a new insole is designed which redistributes pressure following the analysis of characteristic points of plantar pressure, and practical evaluation during walking of subjects while wearing the insole. In total, 10 subjects with flexible flatfeet have participated in the performance of gait experiments by wearing flat insoles, orthotic insoles, and plantar pressure redistribution insoles (PPRI). The results showed that the stance time of PPRI was significantly lower than that of the flat insoles under slow gait. PPRI in the second to third metatarsal and medial heel area showed better unloading capabilities than orthotic insoles. In the metatarsal and heel area, the PPRI also had its advantage in percentage of contact area compared to flat insole and orthotic insole. The results prove that PPRI improves the plantar pressure distribution and gait efficiency of adults with flexible flatfeet, and can be applied into clinical application.

Orthotic Insoles Improve Gait Symmetry and Reduce Immediate Pain in Subjects With Mild Leg Length Discrepancy

Background: Mild leg length discrepancy can lead to musculoskeletal disorders; however, the magnitude starting from which leg length discrepancy alters the biomechanics of gait or benefits from treatment interventions is not clear.Research question: The aim of the current study was to examine the immediate effects of orthotic insoles on gait symmetry and pain on mild leg length discrepancy according to two groups of the leg length discrepancy (i.e., LLD ≤ 1 cm vs. LLD > 1 cm).Methods: Forty-six adults with mild leg length discrepancy were retrospectively included and classified into two groups (GLLD≤1cm or GLLD>1cm). All subjects underwent routine 3D gait analysis with and without orthotic insoles. The symmetry index was calculated to assess changes in gait symmetry between the right and left limbs. Pain was rated without (in standing) and with the orthotic insoles (after 30 min of use) on a visual analog scale.Results: There was a significant improvement in the symmetry index of the pelvis in the frontal plane (p = 0.001) and the ankle in the sagittal plane (p = 0.010) in the stance with the orthotic insoles independent from the group. Pain reduced significantly with the orthotic insoles independently from the group (p < 0.001).Significance: Orthotic insoles significantly improved gait symmetry in the pelvis in the frontal plane and the ankle in the sagittal plane, as well as pain in all subjects (both LLD ≤ 1 cm and LLD > 1 cm) suggesting that it may be appropriate to treat even mild leg length discrepancy.

Research and development of 3D printing orthotic insoles and preliminary treatment of leg length discrepancy patients

BACKGROUND: Leg length discrepancy (LLD) can cause abnormal posture, muscle and/or joint pains, which leads to walking difficulties. The common treatment is to use a shoe lift on the shorter leg side, but this has unsatisfying results. OBJECTIVE: Through research and development, we created 3D printing orthotic insoles for LLD patients and aimed to improve their symptoms. METHODS: 1. Research and development of 3D printing orthotic insole: (1) foot scan and data acquisition; (2) insole software modeling; (3) 3D printing insole using TPU materials, and (4) post-processing. 2. Clinical observation: we customized insoles for LLD patients and required them to wear them while walking. We conducted general inquiries and a functional evaluation before and after 12 weeks of wearing insoles. RESULTS: There are seven complete cases. The joint and lower back pains were alleviated. The stride frequency, stride and pace were improved in all seven cases. Patients’ overall health condition improved significantly. CONCLUSIONS: The 3D printing orthotic insoles are made with clear procedures and practical operability. By wearing insoles, patients’ muscle and/or joint pains were relieved and their gaits were improved.

Effects of Orthotic Insoles on Gait Kinematics and Low Back Pain in Subjects with Mild Leg Length Discrepancy

Background: Mild leg length discrepancy (LLD) increases the biomechanical asymmetry during gait, which leads to low back pain (LBP). Orthotic insoles (OI) with a directly integrated heel lift were used to reduce this asymmetry and thus the associated LBP. The aim of this study was to analyze the biomechanical adaptations of the locomotor apparatus during gait and the subjective pain ratings before and after the establishment of OI use. Methods: Eight subjects with mild LLD ({less than or equal to} 2.0 cm) underwent 3-dimensional biomechanical analysis while walking, before and after 3 weeks of OI use. LBP was assessed separately before both measurement sessions using a visual analogue scale. Results: The analysis of the kinematic parameters highlighted individual adaptations. The symmetry index (SI) of Robinson indicated that OI had no significant effect on the kinematic gait parameters and an unpredictable effect across subjects. OI use significantly and systematically (in all subjects) reduced LBP (P < 0.05), which was correlated with changes in ankle kinematics (P = 0.02, r = 0.80). Conclusions: The effects of OI on gait symmetry are unpredictable and specific to each subject's individual manner of biomechanical compensation. The reduction in LBP seems associated with the improved ankle kinematics during gait.

Utilization of rapid prototyping technology for the fabrication of an orthopedic shoe inserts for foot pain reprieve using thermo-softening viscoelastic polymers: A novel experimental approach

This research work has been completed by concentrating on the structure of inserts for foot orthosis fabricated by utilizing rapid prototyping technology. Thermoplastic elastomer and thermoplastic polyurethane are the most commonly used materials that are being used in customized three-dimensional printed orthotic insoles, which are comfortable and prevent the user in many foot disorders. Thermo-softening viscoelastic polymers, explicitly Filaflex and Ninjaflex, have been printed by utilizing Flash Forge three-dimensional printers to evaluate the mechanical properties of specimens with alterations of the percentage rate fill-up design replicas. The results are compared on the basis of hardness test, flexural/bending test, and tensile test using Durometer and Universal Testing Machine (UTM). It has also been observed that the most significant effecting factor is infill density.

Does Flexible Flatfoot Require Treatment?: Plantar Pressure Effects of Wearing Over-the-Counter Insoles when Walking on a Level Surface and Up and Down Stairs in Adults with Flexible Flatfoot

Background: Orthotic insole is a popular physiotherapy for flatfoot. However, the effects and whether flexible flatfoot needs orthotic insole treatment are not clear, and how the plantar pressure changes while walking up and down stairs has not been studied. Therefore, this study observed the plantar pressures of different walking conditions to find the answers. Methods: Fifteen adults with flexible flatfoot and 15 adults with normal foot were examined while walking on a level surface and while walking up and down 10- and 20-cm stairs before treatment. The maximum force and the arch index were acquired with a force plate system. Participants with flexible flatfoot were instructed to wear the orthotic insoles for 3 months, and plantar pressures were measured again after treatment. The repeated measure was performed to analyze the data. Results: The maximum force and the arch index of flatfoot after treatment were significantly decreased under different walking conditions (P < .01). When walking down 10- and 20-cm stairs, the plantar data of normal foot and flatfoot were significantly increased (P < .05). Conclusions: Orthotic insoles could effectively improve the plantar pressure of flatfoot under different walking conditions. In addition, the arches of normal foot and flatfoot were obviously influenced when walking down stairs. It is, therefore, necessary to wear orthotic insoles for flexible flatfoot to prevent further deformation.