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ObjectiveTo review the classification of orthopedic insoles, common techniques of 3D printing orthopedic insoles, common materials and their application for flatfoot. MethodsLiteratures were retrieved from PubMed, Web of Science, CNKI and Wanfang Data from 2012 to 2022, and the relevant contents were summarized. ResultsA total of ten studies were finally included, from 5 countries, involving 290 participants, which published from 2019 to 2022. Orthotic insoles were classified as prefabricated, semi-custom, and custom, while custom ones were classified as traditional custom and 3D printed custom. 3D printed orthotic insoles were often made with selective laser sintering, fused deposition modeling (FDM) and PolyJet printing technologies, and commonly used materials included ethylene-vinyl acetate (EVA), polylactic acid, thermoplastic polyurethane, polyamide, and polypropylene. For flatfoot, 3D printed orthotic insoles could improve plantar pressure, relieve foot pain and the combined use of insole posting could control rearfoot valgus. Conclusion3D printed custom insoles can be made more efficiently and accurately than traditional custom insoles. The printing technologies and materials often chosen for 3D printed orthotic insoles are mainly FDM and EVA. 3D printed orthotic insoles is effective on plantar pressure, comfort and foot movement function of flatfoot.
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Objective An X-shaped cushioning insole with variable stiffness was designed to explore its effects on plantar pressure and internal stress of diabetic patients with toe amputation. Methods Based on CT images, the feet-calf finite element model of diabetic patients with toe amputation was established, and the insole was divided into different areas according to distribution characteristics of the planter pressure. The three-dimensional (3D) printed cushioning insole with an X-shaped sandwich structure was designed. The modulus of the sandwichstructure was changed by changing thickness of the sandwich structure panel. For simulation analysis, the divided area was filled with the X-shaped sandwich structure with different modulus. Results The peak plantar pressure of diabetic patients with toe amputation was in calcaneal region, and the combined insoles with 1. 2 mpanel thickness in toe area, 1. 4 mm panel thickness in metatarsal area, 2. 0 mm panel thickness in middle area and 1. 6 mm panel thickness in heel area had the best decompression effect. Compared with bare feet, the peak pressure in heel area of the insole, the peak pressure in phalangeal head area and the stress in plantar softissues were reduced by 40. 18% , 31. 7% , and 50. 44% , respectively. Conclusions The 3D printed insoles with variable stiffness can effectively reduce surface pressure and internal stress of the sole and reduce probability of the 2nd toe amputation
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Objective A practical and highly accurate algorithm for dynamic monitoring of plantar pressure was proposed, the magnitude of vertical ground reaction force (vGRF) during walking was measured by a capacitive insole sensor, and reliability of the prediction accuracy was verified. Methods Four healthy male subjects were require to wear capacitive insole sensors, and their fast walking and slow walking data were collected by Kistler three-dimensional (3D) force platform. The data collected by the capacitive insole sensors were pixelated, and then the processed data were fed into a residual neural network, ResNet18, to obtain high-precision vGRF. Results Compared with analysis of the data collected from Kister force platform, the normalized root mean square error (NRMSE) for fast walking and slow walking were 8.40% and 6.54%, respectively, and the Pearman correlation coefficient was larger than 0.96. Conclusions This study provides a novel algorithm for dynamic measurement of GRF in mobile scenarios, which can be used for estimation of complete GRF outside the laboratory without being constrained by the number and location of force plates. Potential application areas include gait analysis and efficient capture of pathological gaits.
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Objective To study topological structure of a new type of three-dimensional (3D) printed height increasing insoles for leg length discrepancy (LLD) and its effect on biomechanics of lower limbs. Methods Topological structure for middle and rear part of the insole was optimized by solid isotropic microstructures with penalization (SIMP), the force was loaded and the boundary conditions were set according to force area of the insole, and the height increasing insole with thermoplastic polyurethanes (TPU) materials was printed by selected laser sintering (SLS). The insoles were used in 9 patients with LLD, visual analogue scale (VAS) and Maryland foot function scores were used to compare pain and foot function changes of patients before and after using the insole, and the 3D gait analysis system was used to compare spatiotemporal parameters and vertical ground reaction force (vGRF) of both lower limbs. Result sAfter the patient wore 3D printed insole, VAS scores decreased, Maryland foot function scores increased, vGRF of both lower limbs decreased, and the difference of cadence, stance phase and swing phase in both lower limbs decreased. Conclusions The 3D printed height increasing insole after topology optimization can improve coordination of lower limb movement, reduce ground impact, relieve pain and improve foot function, thus providing an effective personalized orthopedic plan for LLD treatment in clinic.
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Older adults have decreased control of body balance with aging and are prone to fall. As the primary point of contact between human body and ground, footwear is critical for stability of older adults. The relationship between shoe characteristics and stability of older adults was systematically reviewed to determine the effect of footwear characteristics on stability of older adults. The results show that wearing shoes with shoelaces or velcro, low heels, wide outsole and appropriate soles, or using vibrating insoles and arch support insoles can help older adults improve their stability. Excessive sole spring and low sole hardness may have adverse effects on stability of older adults. This study can provide theoretical references for older adults to choose shoes reasonably and for the manufacturers to design and make shoes to prevent falls.
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Objective Through the evaluation of subjective comfort and plantar pressure during walking, with the integration of subjective perception and biomechanical indexes, to explore the effect of personalized insole on foot perception and ankle function of normal foot. Methods Sixteen male subjects with normal foot types were recruited, and the visual analog scale (VAS) was used to evaluate the differences of subjective comfort index under the intervention of minimalist shoes and personalized insoles, and changes of time and plantar pressures at each stage of barefoot walking and walking with minimalist shoes and personalized insoles were analyzed by single factor repeated measurement variance. Multiple linear regression was used to screen the main indexes which affected the overall comfort of shoes during walking with minimalist shoes and personalized insoles. Results For measurement of plantar pressures, the gait support buffer stage of walking with shoes was higher than that of barefoot walking or walking with minimalist shoes(P<0.05), and the dynamic arch index (AI) of walking with personalized insole was higher than that of walking with minimalist shoes and barefoot walking(P<0.05). The dynamic AI during walking with minimalist shoes was higher than that of barefoot walking(P<0.05), and the proportion of foot impulse during walking with personalized insoles was higher than that during barefoot walking(P<0.05). When wearing shoes, the average slope for center of pressure (COP) trajectory was lower than that of barefoot walking, and the slope of COP trajectory of walking with personalized insoles was lower than that of walking with minimalist shoes(P<0.05). For evaluation of subjective comfort, the overall comfort, heel cushioning, front foot cushioning, arch support, forefoot wrapping and foot control of walking with personalized insoles were higher than those of walking with minimalist shoes(P<0.05). The results of linear regression showed that arch support and the proportion of middle foot impulse had significant influences on the overall comfort of walking with shoes(P<0.05). Conclusions Personalized insoles can improve the overall comfort of normal foot mainly through the influence of foot arch. After personalized insole is added, the cushioning ability and foot control ability of walking are improved, and force deviation of the foot on coronal axis is reduced. Feet-insoles-shoes jointly affect the perception of human feet, and insoles should be selected in many aspects, such as foot types, shoe conditions and insole materials.
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Objective:To observe the effect of braces combined with insoles on scoliosis and walking performance in patients with adolescent idiopathic scoliosis (AIS). Methods:From September, 2019 to September, 2020, 42 subjects with AIS were selected and randomly divided into brace group (n = 21) and brace combined with insole group (n = 21). Both groups received two-month routine rehabilitation, including braces for 22 to 23 hours a day and gymnastics for 30 minutes a day. The brace combined with insole group additionally wore insoles, at least eight hours a day for two months. Meanwhile, 32 even-aged adolescents were recruited as healthy controls. Firstly, gait and plantar pressure of 42 patients and 32 healthy adolescents were compared to find out abnormal indicators. Secondly, the scoliosis and above abnormal indicators were compared between the brace group and the brace combined with insole group Results:The center of pressure excursion index (CPEI) was higher in AIS group than in the healthy group (F = 3.120, P < 0.05), and there was no significant difference in walking speed, gait cycle and phase between two groups (P>0.05). An obvious imbalanced pressure was observed between the medial and lateral heel of the single foot and the bilateral foot in AIS patients (P < 0.05). After treatment, the Cobb's angle decreased in AIS patients (t > 7.552, P < 0.001), however, no difference was found between the brace group and the brace combined with insole group (t = 0.459, P > 0.05); the CPEI decreased (t = 2.209, P < 0.05), and the pressure in medial and lateral heel as well as the left and right foot tended to be balanced (t > 2.306, P < 0.05) in the brace combined with insole group, and were better than that of the brace group (|t| > 2.319, P < 0.05). Conclusion:Plantar pressure distribution shows obvious local and global asymmetric changes in AIS patients. The efficacy of insoles on the scoliosis is limited, but the insole can effectively improve the abnormal biomechanics and balance the force.
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Objective:To investigate the plantar pressure features of diabetic patients, and design the offloading structure of insole to reduce the plantar pressure and internal stress of the soft tissue. Methods:A three-dimensional finite element model of foot was established based on CT images. Hole structure was designed in the high plantar pressure area of diabetic patients. The effects of diameter, depth and interval of holes on plantar pressure was analyzed through orthogonal test and finite element analysis, to obtain the optimal scheme; and the offloading effect was analyzed with finite element analysis and experiment. Results:The peak plantar pressure was higher in diabetic patients than in healthy individuals. The holes with 5 mm diameter, 6 mm depth and 2 mm interval in metatarsal and calcaneus regions might effectively reduce the plantar pressure and internal stress of soft tissue, which was 15.6%, 45.6%, 53.5% and 10.1% less of the peak plantar pressure on toes, metatarsal, midfoot and calcaneus area, respectively, compared to walking without insoles. Conclusion:Finite element analysis is helpful to explore the internal stress of soft tissue in diabetic patients, and insole with hole structure can reduce the plantar pressure and internal stress of soft tissue.
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Objective To design a kind of customized insole with zonal gradient hardness for people with high arch foot in need of plantar decompression. Methods A functional gradient structure was designed and applied to the customized insole. Porous elements with corresponding elastic modulus were used in different areas of insole. The relationship between structural element parameters and modulus was studied through mechanical tests. The foot geometry and plantar pressure distribution data of volunteers were collected, and the plantar region was divided according to the pressure contour line, so as to assemble the structural unit. Four kinds of customized insoles were designed: ordinary flat insole, optimized flat insole, ordinary full contact insole and optimized full contact insole. Through plantar pressure test experiment, the optimization design of sub region was verified. Results The designed insole could reduce the peak pressure of high arch foot by 52.8% in static standing state and 18.43% in gait condition. Conclusions This method can be used to design customized insoles, such as functional insoles for patients with diabetes and high arch feet, by providing better decompression function. The research findings provide references for conservative treatment of foot diseases with decompression needs.
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Forefoot disorders are often seen in clinical practice. Forefoot deformity and pain can deteriorate gait function and decrease quality of life. This review presents common forefoot disorders and conservative treatment using an insole or orthosis. Metatarsalgia is a painful foot condition affecting the metatarsal (MT) region of the foot. A MT pad, MT bar, or forefoot cushion can be used to alleviate MT pain. Hallux valgus is a deformity characterized by medial deviation of the first MT and lateral deviation of the hallux. A toe spreader, valgus splint, and bunion shield are commonly applied to patients with hallux valgus. Hallux limitus and hallux rigidus refer to painful limitations of dorsiflexion of the first metatarsophalangeal joint. A kinetic wedge foot orthosis or rocker sole can help relieve symptoms from hallux limitus or rigidus. Hammer, claw, and mallet toes are sagittal plane deformities of the lesser toes. Toe sleeve or padding can be applied over high-pressure areas in the proximal or distal interphalangeal joints or under the MT heads. An MT off-loading insole can also be used to alleviate symptoms following lesser toe deformities. Morton's neuroma is a benign neuroma of an intermetatarsal plantar nerve that leads to a painful condition affecting the MT area. The MT bar, the plantar pad, or a more cushioned insole would be useful. In addition, patients with any of the above various forefoot disorders should avoid tight-fitting or high-heeled shoes. Applying an insole or orthosis and wearing proper shoes can be beneficial for managing forefoot disorders.
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Animals , Humans , Congenital Abnormalities , Foot , Foot Orthoses , Gait , Hallux , Hallux Limitus , Hallux Rigidus , Hallux Valgus , Hammer Toe Syndrome , Head , Hoof and Claw , Joints , Metatarsal Bones , Metatarsalgia , Metatarsophalangeal Joint , Neuroma , Orthotic Devices , Quality of Life , Shoes , Splints , ToesABSTRACT
Objective:To evaluate the effects of sensomotor insole (SMI) on gait and energy expenditure in children with spastic cerebral palsy during walking. Methods:From December, 2014 to March, 2016, 42 children with spastic cerebral palsy aged three to 15 years were recruited. Their gait parameters and energy expenditure of six minute walking were measured under two test conditions: walking with shoes and walking with shoes and SMI. Results:After wearing SMI, the walking distance, speed, left step length and right step length were all greater (t = -6.022~-4.331, Z= -4.814~-4.183, P < 0.001), the both feet single limb support was shorter (t = 2.954, P < 0.05), and the energy expenditure was higher than before (t = -2.358, P < 0.05). Conclusion:SMI as a sort of orthopedic insole, could improve the gait parameters of children with cerebral palsy immediately after wearing it, and increase the energy expenditure slightly.
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@#Working in prolonged standing position among industrial workers has been shown to be associated with different potentially serious health outcomes, namely lower back pain, leg pain, fatigue, discomfort, and other health issues. Personalisation of insole offers a solution that will provide a perfect fit and comfort to the shoes wearer based on the ergonomic considerations. It works in a way that it alters the pressure away from painful areas by increasing the surface area that supports the weight of the body and evenly distributes it to the whole plantar area. Survey was conducted among workers at a manufacturing industry company to study on the level of pain experienced by them together with their foot anthropometry. Then, the foot pressure of each of the workers was collected by using pressure measurement device (F-scan). Combination of these data was used to design the customized insole that is fit for the worker. The personalised insoles were fabricated by using Additive Manufacturing technology. After that, the insoles were validated by using the F-scan and Electromyogram (EMG) to ensure their effectiveness in reducing pressures on the foot and muscle activity hence improving the comfort of the shoe wearer. At the end of the experiment, it was found that the insole is able to reduce the peak pressure of four out of five areas of the worker’s foot with the reduction of pressure percentage ranging from 6% to 28%.
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PURPOSE: The most common cause of plantar ulceration is an excessive plantar pressure in patients with peripheral neuropathy. Foot orthosis and therapeutic footwear have been used to decrease the plantar pressure and prevent the plantar ulceration in in diabetes patients. We investigated whether protective sock with functional insoles reduce plantar pressure while walking in 17 diabetes patients. METHODS: An in-shoe measurement device was used to measure the peak plantar pressure while walking. Peak plantar pressure data were collected while walking under two conditions: 1) wearing diabetic sock and 2) wearing the protective sock with functional insoles. Each subject walked 3 times in 10-m corridor under three conditions, and data were collected in 3 steps in the middle of corridor with in right and left feet, respectively. Pared t-test was used to compare the peak plantar pressures in three plantar areas under these two conditions. RESULTS: The protective sock with functional insoles significantly reduced the peak plantar pressure on the lateral rearfoot, but significantly increased the peak plantar pressure on the middle forefoot, and medial midfoot (p 0.05). CONCLUSION: The protective sock with functional insoles reduced plantar pressures in the rearfoot and supported the medial longitudinal arch. However, it is necessary to change the position of metatarsal pad in the insole design of forefoot area to prevent diabetic foot ulceration.
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Humans , Diabetes Mellitus , Diabetic Foot , Foot Orthoses , Foot Ulcer , Foot , Metatarsal Bones , Peripheral Nervous System Diseases , Ulcer , WalkingABSTRACT
Objective To explore the effect on walking ability of the orthotic insole produced by the International College of Biomechanics (ICB) when it is combined with an ankle foot orthosis (AFO).Methods A total of 40 stroke survivors with hemiplegia were randomly divided into an observation group and a control group,each of 20.In addition to conventional medical treatment and rehabilitation,the control group received AFOs and walking rehabilitation training.The observation group accepted walking training with an ICB orthotic insole combined with an AFO.The experiment lasted 4 weeks.Timed up and go test (TUGT) times,10 m maximum walking speed (10 m MWS) and Berg balance scale (BBS) ratings were recorded before and after the treatment.Results Before the treatment there was no significant difference between the group averages in terms of any of the measures.After the treatment,significant improvement was observed in all of the measurements,with the improvements in the observation group significantly better than those in the control group,on average.Conclusion An ICB orthotic insole combined with an AFO results in better improvements in the walking ability of hemiplegic subjects than an AFO alone.
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[Objective] To explore the characteristics of the plantar pressure data of the patients with adolescent idiopathic scoliosis (AIS).[Methods] 56 AIS patients who were diagnosed from October 2015 to March 2017 in the East branch of the First Affiliated Hospital of Sun Yat-sen University divided into 3 groups,18 cases in spinal lateral bending to right,18 cases in spinal lateral bending to left,20 cases in type S who were thoracolumbar scoliosis.Another 19 healthy persons were as the control group.The left and right foot pressure,half foot pressure and other biomechanical data were compared.The changes of the plantar pressure and the Cobb angle were analyzed with the patients who wore orthopedic insoles.[Results] Compared with the control group,the mean pressure of the left foot and the pressure of the left anterior half of the right bending group were less than those of the control group,and the right half foot pressure were greater than those of the control group (P ＜ 0.017).To the left bending group,the mean pressure of right anterior half foot were less than those of the control group,and the right rear half foot pressure was greater than that of the control group (P ＜ 0.017).The pressure of the left anterior half foot of the S type scoliosis group was less than that of the control group.To the right bending group,the left foot average pressure (44.7％±6.0％) was significantly less than the average pressure of right foot (55.4％ ± 6.0％).There was no difference in bilateral plantar pressure of the left bending group,S type group and control group.There was difference with the plantar pressure distribution in patients with only one curve after they wore orthotic insoles,but there was no difference in patients with type S.There was no significant difference in the Cobb angle after the patients wearing the orthotic insoles (P =0.102).[Conclusions] The right and left foot pressure symmetry of the right bending patients is poor,but the left and right plantar pressure in the patients with type S is symmetrical.The orthotic insole can be used to adjust the plantar pressure distribution in patients with a single curved scoliosis (left or right),but their effect on the patient's spinal lateral curvature should be further observed.
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OBJECTIVE: To clarify the relationship of the initial radiologic and a biomechanical parameter at first clinical visit, and define the effectiveness of modified insole, following insole fitting in children with flexible flatfoot. METHODS: Children aged less than 13 years with flexible flatfoot were enrolled. The total number of subjects was 66 (33 boys, 33 girls). The subjects were divided into 5 subgroups, based on age: 1–2, 3–4, 5–6, 7–9, and 10–12 years. The mean time period between the initial & final examination for their resting calcaneal stance position angle (RCSPA) was 24 months. Radiography quantified the deformity by measuring angles, including the talometatarsal angle, the metatarsal angle, and the calcaneal pitch angle. RESULTS: From the angles measured on radiographs, only the talometatarsal angle showed a statistically significant correlation to the initial RCSPA (r=-0.578 for right side, r=-0.524 for left side; p<0.01). The mean RCSPA improved in all subgroups of subjects following insole fitting. Moreover, in children younger than 7 years, the improvement in RCSPA from the insole fitting was greater compared to children aged 7 years and older. CONCLUSION: The insole has additionally beneficial effects in all populations younger than 13 years. However, there might exist a hidden effect of normal structural pedal alignment during growth accompanied with bony maturation and developmental process. To date, it is controversial whether the treatment of flexible flatfoot is necessary in the vast majority of cases, or simple observation and advice to parents would suffice.
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Child , Humans , Congenital Abnormalities , Flatfoot , Metatarsal Bones , Parents , RadiographyABSTRACT
Objective To investigate the effects of insole parameter changes on biomechanical mechanism of heel pain by finite element methods. Methods The 3D finite element model of foot, crus bones, gastrocnemius muscle and knee joint was reconstructed based on CT images. The plantar pressure distribution and peak pressure were calculated by changing the shape, thickness and hardness of the insole. Results The distribution of plantar pressure calculated by the finite element model was generally consistent with that measured by the pressure plate, and the values were very close. Compared with the barefoot standing, the peak pressure of the heel was decreased by 20.5%, 59.2% and 38.4%, and that of the metatarsal head was decreased by 9.9%, 18.1% and 46.7%, with flat insole, half-contact insole and full-contact insole, respectively. For patients with heel pain, the pressure peak of the heel and the metatarsal head at plantar surface decreased with the conventional thickness of insole increasing and the hardness of insole decreasing. Conclusions The changes in insole parameters have a significant influence on the plantar pressure distribution. Finite element analysis can contribute to discovering the etiology and pathology of heel pain, so as to provide the theoretical basis for clinical treatment.
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Objective To study the effect of lateral wedge insoles with different stiffness on the knee adduction moment (KAM) under walking condition. Methods The gait of 15 healthy males wearing lateral wedge insoles with different stiffness was tested. The kinetics and kinematics data were collected by optical motion capture system and ground reaction force platform. The KAM and its peak values were calculated by Visual 3D software. The differences in peak KAM under 3 walking conditions (shoes only, shoes with softer or harder lateral wedge insoles) were analyzed. Results Compared with walking with the softer lateral wedge insoles, walking with the harder lateral wedge insoles could reduce the 1st and 2nd peak KAM by 9.3% and 9.7%, respectively, with significant statistic differences. Conclusions Increasing some stiffness of lateral wedge insoles can further reduce the pressure and wear on medial compartment of the knee joint, which may relieve the symptom of knee osteoarthritis.
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Objective To study the effect of lateral wedge insoles with different stiffness on the knee adduction moment (KAM) under walking condition.Methods The gait of 15 healthy males wearing lateral wedge insoles with different stiffness was tested.The kinetics and kinematics data were collected by optical motion capture system and ground reaction force platform.The KAM and its peak values were calculated by Visual 3D software.The differences in peak KAM under 3 walking conditions (shoes only,shoes with softer or harder lateral wedge insoles) were analyzed.Results Compared with walking with the softer lateral wedge insoles,walking with the harder lateral wedge insoles could reduce the 1st and 2nd peak KAM by 9.3％ and 9.7％,respectively,with significant statistic differences.Conclusions Increasing some stiffness of lateral wedge insoles can further reduce the pressure and wear on medial compartment of the knee joint,which may relieve the symptom of knee osteoarthritis.
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Objective To investigate the effects of insole parameter changes on biomechanical mechanism of heel pain by finite element methods.Methods The 3D finite element model of foot,crus bones,gastrocnemius muscle and knee joint was reconstructed based on CT images.The plantar pressure distribution and peak pressure were calculated by changing the shape,thickness and hardness of the insole.Results The distribution of plantar pressure calculated by the finite element model was generally consistent with that measured by the pressure plate,and the values were very close.Compared with the barefoot standing,the peak pressure of the heel was decreased by 20.5％,59.2％ and 38.4％,and that of the metatarsal head was decreased by 9.9％,18.1％ and 46.7％,with flat insole,half-contact insole and full-contact insole,respectively.For patients with heel pain,the pressure peak of the heel and the metatarsal head at plantar surface decreased with the conventional thickness of insole increasing and the hardness of insole decreasing.Conclusions The changes in insole parameters have a significant influence on the plantar pressure distribution.Finite element analysis can contribute to discovering the etiology and pathology of heel pain,so as to provide the theoretical basis for clinical treatment.