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Objective To analyze the influence of different backpack types and loads on kinematics and plantar pressure of college students during stair climbing, so as to provide references for choosing the appropriate backpack and carrying mode. Methods The Nokov infrared light point motion capture system and Podome plantar pressure system were used to analyze the differences in the range of motion ( ROM) of the trunk and lower limb joints, the kinematic parameters at the peak time, the peak pressure of each plantar partition, the contact time, the maximum pressure of the whole foot, the average pressure and the maximum contact area for 15 male college students during the support period of stair climbing. Results The 5% BW and 10% BW backpack loads reduced ROM of trunk rotation, increased ROM of ankle flexion/ extension and varus / valgus. The 10% BW backpack loads increased the peak pressure of the 1st and 3rd metatarsals bones and the maximum pressure of the whole foot ( P < 0. 05). Single-shoulder bag and handbag reduced ROM of trunk tilting and rotation, and increased ROM of ankle flexion and extension, hip flexion angle, peak pressure of foot arch and medial heel (P<0. 05). The double-shoulder bag loads increased peak pressure in the toe area (P<0. 05). Conclusions During walking on the stairs, the 5% BW and 10% BW backpack loads limited trunk rotation and increased ankle ROM. The 10% BW loads also increased the load in metatarsal area. The unilateral weight-bearing mode would make the trunk tilt to the unload side and rotate to the weight-bearing side. The pressure in toe area was higher when carrying double-shoulder bag, while single-shoulder bag and handbag mainly increased the pressure of arch foot and medial heel. It is suggested that college students choose symmetrical backpack scheme, and wisely allocate back weight to avoid the injury of foot area.
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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 To compare the differences in kinematic parameters and plantar pressures for two types of knee varus with tibial and femoral origins in gait analysis, so as to provide biomechanical theoretical basis for different types of genu varus. Methods Twenty-six patients with unilateral knee osteoarthritis (KOA) varus genu were enrolled, with 13 from femoral and 13 from tibial sources. Using Noraxon MyoMotion three-dimensional (3D) motion capture system and Footscan plantar pressure test system, the gait of the subjects during natural walking was measured, the temporal and spatial parameters of the gait, the kinematics parameters of lower limb joints and plantar pressures were collected, to make comparative analysis between the two groups. Results The range of knee flexion and extension of tibial varus, the peak of hip abduction, the range of motion (ROM) of hip adduction and abduction and the peak of ankle pronation were larger than those of femoral lateral genu varus. The peak of knee flexion and hip adduction was smaller than that of femoral lateral genu varus. Compared with femoral varus, subjects with tibial varus had increased stress time and peak pressure on the plantar of the 4th and 5th metatarsals (P<0.05). In the 3rd metatarsal region, the impulse of healthy femoral limb was greater than that of healthy limb with tibial deformity. While in the medial calcaneal region, the impulse of healthy femoral limb was smaller (P<0.05). Conclusions There are some differences in kinematic parameters and plantar pressures between two different types of unilateral genu varus patients. The results of this study are helpful to understand the abnormal gait caused by genu varus, and provide reliable reference for postoperative rehabilitation and limb exercise for different types of genu varus.
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Objective To analyze the plantar pressure distribution of knee osteoarthritis ( KOA) patients after medial opening wedge high tibial osteotomy ( MOWHTO), so as to provide biomechanical references for the surgical treatment and rehabilitation of patients. Methods A total of 31 patients with medial single compartmental KOA after unilateral MOWHTO treatment were selected as the experimental group, and 35 healthy subjects at same age were selected as the control group. The Pedomedic 40 pressure measuring system was used to test dynamic plantar pressure. By comparing the maximum pressure ( pmax ), force-time integral ( FTI) and contact area (CA) of different plantar zones between the experimental group (operative side and unoperated side) and the control group during walking, the changes of plantar pressure in patients with medial single compartmental KOA after MOWHTO were evaluated. Results Compared with the unoperated side and the control group, the CA and FTI of the 1st metatarsal head (MH1) were higher (P<0. 05), the CA of the 4th metatarsal head (MH4)was smaller (P<0. 001), the pmax and FTI of the 5th metatarsal head (MH5) were smaller (P<0. 05), the CA of the lateral middle foot (MF-L) was smaller (P<0. 001), and the CA of the medial rear foot (RF-M) was larger (P<0. 05). Compared with the control group, the pmax of MH1 and MH2 was smaller (P<0. 05), the CA and FTI of MH5 were larger (P<0. 05), the pmax of MF-L was larger (P<0. 001), and the FTI of lateral rear foot (RF-L) was larger (P<0. 05). Conclusions Compared with healthy people, patients with medial single compartmental KOA have abnormal plantar pressure residual after MOWHTO. In clinical practice, targeted intensive rehabilitation therapy is necessary to restore the normal plantar distributions of patients.
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Objective To explore the difference of balance ability between patients with chronic nonspecific low back pain ( CNLBP) and healthy individuals, and the correlation between patients’ pain symptoms, lumbar flexibility, abdominal muscle endurance, overall function, quality of life and fear of avoidance with balance ability, so as to guide clinical rehabilitation evaluation. Methods A total of 34 patients with CNLBP were selected as the experimental group, and 34 healthy volunteers without history of low back pain were selected as control group. The plantar pressure measurement system was used to collect the ratio of forefoot to hindfoot pressure, pathlength ( L) of plantar center of pressure ( COP), displacement length in anteroposterior direction ( LAP ), displacement length in mediolateral direction (LML ), mean velocity (v), displacement velocity in anteroposterior direction (vAP ), displacement velocity in mediolateral direction (V-ML) and elliptical swing area (S). In addition,the experimental group was assessed by the visual analogue scale (VAS), the finger floor distance (FFD), the number of sit-ups in 1 minute, the Oswestry disability index (ODI), the 36-item short form survey (SF-36) and the fear avoidance beliefs questionnaire (FABQ), and correlated with plantar pressure parameters. Results All plantar pressure parameters were significantly different between the two groups ( P < 0. 05). The the ratio of forefoot to hindfoot pressure in experimental group was significantly lower than that in control group (P<0. 05), and the parameters L, LAP , LML , v, vAP , vML and S were significantly higher than those of control group (P<0. 05). With eyes open or closed, the VAS score of experimental group was positively correlated with L, LAP , LML(P<0. 05), and FFD and FABQ scores were positively correlated with L and LML , respectively (P< 0. 05). With eyes open, ODI was positively correlated with L, LAP and LML (P< 0. 05), and SF-36 score was negatively correlated with L and LML(P<0. 05). With eyes closed, the number of 1-min sit-ups was negatively correlated with LAP and S (P<0. 05), ODI was positively correlated with L and LML(P<0. 05), and the SF-36 score was negatively correlated with L (P<0. 05). Conclusions The static balance ability of patients with CNLBP is decreased, and it is correlated with pain symptoms, lumbar function, quality of life and psychological status. The result can provide references for the assessment of functional activities.
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ObjectiveTo analyze the characteristics of plantar pressure of diabetic patients during gait cycle, and to design a offloading insole with variable stiffness. MethodsThe plantar pressure experiment was carried out and a database including 157 subjects was established. The differences of plantar pressure distribution were analyzed among diabetic patients with and without peripheral neuropathy, and healthy people. The insole pressure area was divided, and porous units were filled in different insole areas according to the pressure gradient. The fed-calf-insole finite element model of diabetic patients was constructed. The simulation analysis of different insole schemes was carried out under the conditions of push-off, footheel-strike and dynamic neutrality posture, and to explore the most reasonable insole stiffness design. ResultsCompared with the healthy group, the percentage of peak pressure and high pressure in the left and right heel areas of diabetic neuropathy patients showed a decreasing trend, in which the left peak pressure was significantly reduced by 11% (P = 0.026) and the percentage of high pressure was significantly reduced by 9.8% (P = 0.02). When the porous elements of 2.5 MPa and 1.9 MPa were used in the high pressure area of the insole metatarsal and high pressure area of the heel, the peak plantar pressure of footheel-strike, dynamic neutral and push-off was reduced by 42.4%, 27.4% and 26.4%, and the peak stress of the soft tissue was reduced by 49.8%, 43.6% and 25.1%, respectively. ConclusionThere is a higher risk of ulcer in the metatarsal region than in the heel region for diabetic patients. The variable stiffness insoles based on the optimization of plantar pressure and internal stress under multi-posture can effectively reduce the peak pressure of plantar and peak stress of soft tissue during walking, which provides a reference for the design of variable stiffness insoles.
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Objective To develop plantar force model of patellofemoral pain (PFP), so as to provide theoretical references for the assessment of PFP rehabilitation. Methods The case-control study was conducted, and a total of 126 patients with PFP and 126 healthy controls matched by gender and age were enrolled in the study. The participants were tested for plantar force and pressure during level walking, and twelve plantar regions were divided and recorded. Whether the participants suffered PFP was analyzed as dependent variable, meanwhile the peak force and peak pressure in 12 plantar regions of participants at selected speed during level walking were analyzed as independent variables. Conditional logistic regression (CLR) equations of peak force and peak pressure with PFP were established, respectively. The receiver-operating characteristic (ROC) curve of the corresponding equations was derived, and the area under ROC curve was calculated to analyzed the validity of different equations on PFP assessment. Results The CLC equation of peak force in 12 plantar regions of the participants with FFP was constructed, and only peak force of lateral heel was in the equation. The CLC equation of peak pressure in each plantar region included medial heel, midfoot, 1st and 2nd metatarsals. Meanwhile, the area under ROC curve of the pressure equation was larger than that of the force equation. Conclusions Peak force and pressure at different plantar regions can be used to assess PFP during level walking, and peak pressure is more effective for assessment.
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Objective To explore dynamic characteristics of the gait for the elderly with different fall risks before and after obstacle crossing. Methods Twenty-seven elderly people in community were graded as fall risk by using the time up and go test and five-time sit to stand test. The plantar pressure parameters of the elderly before and after obstacle crossing were measured and analyzed by foot pressure measurement system. Results There was no significant difference in the characteristic value of bimodal curve of overall plantar pressure between the high and low fall risk groups before and after obstacle crossing(P>0.05). The center of pressure (COP) trajectory in X direction of high fall risk group after obstacle crossing was significantly greater than that of low fall risk group (P0.05). Conclusions The support time of the elderly with high fall risk is longer than that of the elderly with low fall risk during obstacle crossing, the peak pressure of plantar metatarsal region of the crossing leg increases, and the plantar COP curve shows asymmetry, with an increase in transverse range of the coronal plane. In clinical evaluation, plantar pressure characteristics of people with fall risks during obstacle crossing should be focused on.
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Objective According to clinical demand of quantification evaluation on flat foot and high arch, an intelligent and rapid method to diagnose arch shape based on principal component analysis (PCA) of plantar pressure is proposed, and its clinic validity is tested. Methods Volunteers diagnozed as abnormal arch and healthy arch were included in this study, and a portable intelligent arch test system was designed and developed. By adopting thin-firm piezoresistive sensor array with 44 rows, 52 columns of sensing units, the system could collect plantar pressure distribution data from the subjects under static standing. Foot axis could be fitted automatically by using the self-programmed PCA, so that foot diagnosis was completed with diagnostic report. The plantar pressure results from the system were compared with those from the existing plantar pressure acquisition device, so as to verify precision of collected data. The accuracy of the diagnosis algorithm for flat foot, high arch and healthy foot was verified through comparison with clinical diagnosis. Results The result of the system had a good correlation with that of the existing plantar pressure acquisition device, the deviation of contact area acquired by the system was smaller than 3.2%, and the angle deviation of the fitted foot axis with clinically defined angel was less than 1°. The system was capable of making diagnosis on arch shape that was 92.6% consistent with the clinical diagnosis. Conclusions PCA is introduced to automatically fit foot axis to achieve the purpose of fast and accurate extraction of foot arch information. The method can be used to assist clinical diagnosis of flat foot and high arch foot, and contribute to quantative analysis on foot arch deformity and its pathogenesis study.
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Objective:To explore any changes with age in the center of plantar pressure among normal people after walking.Methods:Fifty healthy subjects were divided into a young group and an elderly group, each of 25. Gait descriptors were collected for each subject using a model AL-600 gait and balance training and evaluation apparatus. The gait descriptors were the center of pressure displacement (COPD), and the COPD in the medial-lateral (COPD-X) and anterior-posterior (COPD-Y) directions before and after 10 and 15 minutes of walking.Results:The average COPD, COPD-X and COPD-Y of the elderly group increased after both 10 and 15 minutes of walking, but among the young group increases were observed only after 15 minutes. The average COPD, COPD-X and COPD-Y of the elderly group were always significantly larger than the young group′s averages.Conclusions:Gait stability among the elderly decreases after as little as 10 minutes of walking, but among the young decreases are observed only after 15 minutes.
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Objective:To explore the features the gait of elderly persons with type 2 diabetes and peri-pheral neuropathy.Methods:Twenty patients no less than 60 years old with type 2 diabetes and peripheral neuropathy (DPN) formed a DPN group, while 20 counterparts with type 2 diabetes but without peripheral neuropathy composed the DM group, and another 20 healthy counterparts served as a control group. The three groups were tested using the Swedish Qualisys motion capture system and their walking speed, step length, step width, stride frequency and stride length, bipedal foot support phase time, single foot support phase time, peak plantar pressure, and regional-holding time were collected and compared.Results:The average walking speed, stride length and stepping frequency of the DPN group were all significantly lower than the other 2 groups′ averages. Their bipedal support phase was significantly longer, but their single foot support phase time was significantly shorter. And in the DPN group the average first and second peak plantar pressures and the second peak pressure time were significantly greater than the other groups′ averages.Conclusions:Elderly patients with type 2 diabetes and peripheral neuropathy have significant gait abnormalities, decreased walking stability, as well as increased plantar pressure and plantar compression time.
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Objective To analyze the gait characteristics of hip disarticulation amputees, and analyze the reasons for their differences from normal gait, so as to assist clinical diagnosis and evaluation. Methods Through the portable human motion capture device and plantar pressure analysis system, the kinematics and plantar pressure information of 5 hip amputees were collected and compared with 15 healthy volunteers in control group. Gait differences between the amputees and normal subjects and between the affected leg side and the healthy leg side of the amputees were compared. Results The proportion of double-support period for hip amuptees was higher than that of normal gait. Step length, step time, loading response period, mid support period, pre-swing period, proportion of the swing period for the affected leg side and healthy leg side of hip amputees showed significant differences with those of control group. The relative symmetry index of the gait for hip amputees was 0.60±0.05. Compared with the affected leg side, the support period of the healthy leg side was extended, the step length was shortened, the ground reaction force was greater than that of the affected leg side, and the center of pressure trajectory shifted to the affected leg side. Conclusions The gait of hip amputees is significantly different from that of normal people. Hip amputees have weak walking ability, poor gait symmetry, and they lack of continuity in the body’s center of gravity. The results provide experimental basis and theoretical analysis for the design of mechanical structure and control system of novel hip prosthesis.
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Resumen: Introducción: El pie cavo es una patología musculoesquelética con un aumento del arco medial del pie. La etiología del pie cavo aún es incomprensible, está relacionada con afecciones neurológicas, enfermedad de Charcot-Marie-Tooth, ataxia de Friedreich y parálisis cerebral. El objetivo de esta investigación fue analizar la distribución de la presión plantar en atletas jóvenes con pie cavo. Material y métodos: Se reclutaron 83 atletas jóvenes de entre nueve y 20 años de edad, que presentaban patología de pie cavo. La masa y el promedio de altura fueron 56.9 ± 12.36 kg y 1.61 ± 0.10 m, respectivamente. La distribución de la presión plantar de los pies se registró durante condiciones estáticas. Se compararon las presiones del antepié y el retropié. Resultados: La distribución de la presión plantar se categorizó en tres grupos. En el primer grupo los participantes presentaron mayor presión en la parte anterior del pie; en el segundo grupo los atletas mostraron una presión similar en la región posterior y anterior de los pies y en el último los sujetos revelaron una mayor presión en el retropié. Para ser considerado en uno de los tres grupos, la diferencia de presión entre la parte posterior y anterior del pie se estableció en 16%. Conclusión: Muchos trastornos musculoesqueléticos en el cuerpo humano son de origen biomecánico y están relacionados con la anatomía del pie. El pie cavo es una patología con alta prevalencia en atletas y está relacionada con las fuerzas mecánicas sobre los pies en condiciones dinámicas.
Abstract: Introduction: The cavus foot is a musculoskeletal pathology with an increase of the medial arch of the concavity of the foot. The etiology of the cavus foot is still enigmatic, it is related with neurologic conditions, Charcot-Marie-Tooth disease, Friedreich's ataxia, and cerebral palsy. The aim of this research was to analyze the plantar pressure distribution of the feet on young athletes with cavus foot. Material and methods: Eighty-three young athletes between nine and 20 years old, that presented cavus feet pathology were recruited. The mass and height average were 56.9 ± 12.36 kg and 1.61 ± 0.10 m respectively. Plantar pressure distribution of the feet was recorded during static conditions. The hindfoot and forefoot pressure were compared in each foot. Results: The plantar pressure distribution were categorized in three groups. In the first group the participants presented higher pressure in the hindfoot than forefoot, in the second group, the athletes showed similar pressure in the posterior and anterior region of the feet and in the last one, the subjects revealed higher pressure in the forefoot. To be considered in one of the three groups, the difference of pressure between the posterior and anterior part of the foot was established at 16%. Conclusion: Many musculoskeletal disorders in the human body are biomechanical in origin and related with foot anatomy. The cavus foot is a pathology with high prevalence in athletes and it is related with the mechanical forces over the feet during dynamic conditions.
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OBJECTIVE@#To analyze the effects of visual restoration after cataract surgery on plantar pressure and biomechanics of foot in elder individuals.@*METHODS@#Thirty-two patients [male/female 5/27, (70.1±5.2) years old] with age-related cataract were recruited between October 2016 and December 2019. The footscan system was employed to record the data of plantar pressure during level walking before and 1-month after the cataract surgery. Parameters of peak pressure (PP), impulse (I), pressure-time integral (PTI) and time to peak pressure (TPP) from the regions of the 1st toe (T1), 2nd to 5th toes (T2-5), 1st to 5th metatarsal heads (M1-M5), midfoot (MF), medial hindfoot (HM) and lateral hindfoot (HL) were analyzed respectively.@*RESULTS@#Post-operatively, the visual function was effectively reconstructed with improved visual acuity in both eyes (Z=-4.878, -4.801; P < 0.001). The PP (t=2.266, P=0.031) and I (t=2.152, P=0.039) values in M2 region on the dominant side (right foot) increased statistically at post-operative phase, while the changes of pressure and temporal para-meters in other regions remained stable. There was laterality in plantar pressure at pre-operative phase, manifested as greater PP values in M1, M2, MF, and HM regions on the dominant sides (t=-2.414, -2.478, -2.144, -5.269; P < 0.05), greater PP values in T1, M3, M5 and HL regions on the non-dominant sides (t=4.830, 3.155, 2.686, 3.683; P < 0.05), greater I values in M1, MF, and HM regions on the dominant sides (t=-2.380, -2.185, -5.320; P < 0.05) and greater I values in T1, M3, M5 and HL regions on the non-dominant sides (t=4.489, 2.247, 2.838, 3.992; P < 0.05). post-operatively, the pressure tended to be compatible between the two sides in regions of M3 and MF, while the magnitude of laterality in regions of M1 (ZPP△= -2.721, P=0.007; ZI△=-2.581, P=0.010), M2 (ZPP△=-2.674, P=0.007; ZI△=-2.375, P=0.018) and M5 (ZPP△=1.991, P=0.046; ZI△=2.150, P=0.032) was further increased.@*CONCLUSION@#Changes in plantar pressure after cataract surgery were characterized as increased pressure in the 2nd metatarsal head area on the dominant side. Visual restoration might intensify the laterality in the medial of forefoot on the dominant side and the lateral of forefoot on the non-dominant side.
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Aged , Female , Humans , Male , Middle Aged , Biomechanical Phenomena , Foot , PressureABSTRACT
Abstract The aging process causes changes in the physical and functional conditions, as well as in the foot structure and function. This study aimed to analyze the plantar pressure variation with respect to visual information and physical activity in adult and older women. This was a cross-sectional study that included 142 women (mean age of 67.8 years). Participants responded the anamnesis questionnaire, Mini Mental State Examination, and International Physical Activity Questionnaire. Plantar pressure was assessed using computerized baropodometry. Weight distribution was observed in semitandem positions for the right foot forward and then the left foot forward . Data analysis showed that foot type had no correlation with age (p = 0.37 right foot; p = 0.93 left foot) or level of physical activity (p = 0.28 right foot; p = 0.96 left foot). Moreover, plantar pressure variation showed no significant relationship with age (R2 = 0.2; p = 0.6). In conclusion, plantar pressure variation is not associated with the morphological foot type in women analyzed, as the visual condition did not generate plantar pressure variations when compared to its effect on the classification of plantar arches. Furthermore, level of physical activity was not associated with plantar pressure variation .
Resumo O processo de envelhecimento acarreta alterações nas condições físico-funcionais e na estrutura e função do pé. O objetivo do estudo foi analisar a variação da pressão plantar quanto a informação visual e atividade física em mulheres adultas e idosas. Estudo transversal, com uma amostra de 142 mulheres (média de idade de 67,8 anos). As mulheres responderam ao questionário de anamnese, Mini Exame do Estado Mental (MEEM) e o Questionário Internacional de Atividade Física (IPAQ). O exame da pressão plantar foi realizado pela baropodometria computadorizada. A distribuição da pressão plantar foi observada na posição semitandem com o pé direito na frente e com o pé esquerdo à frente. O tipo de pé não teve relação com a variação da pressão plantar, idade (p = 0,37 pé direito e p = 0,93 pé esquerdo) ou atividade física (p = 0,28 pé direito e p = 0,96 pé esquerdo). A variação da pressão plantar também não mostrou relação significativa com idade (R2 = 0,2 e p = 0,6). Conclui-se que a variação da pressão plantar não está associada com o tipo morfológico do pé das mulheres analisadas, pois a condição visual não gerou variação da pressão plantar quando comparada ao seu efeito na classificação dos arcos plantares. O nível de atividade física não apresentou relação na variação da pressão plantar.
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Objective To analyze the statistical behavior of plantar pressure distribution, extract the characteristics of foot movement, and provide references for application of gait recognition in medical clinical diagnosis, rehabilitation training and public health. Methods The collected foot pressure data were prepossessed, statistical analysis on the data was performed, the footprint reconstruction was realized, and the pressure distribution rates of the footprints, segmented regions and each region were compared and analyzed, so as to decompose the foot motion characteristics. Results Based on the cross point of pressure peak curve in different regions, the plantar region was divided into toe region, metatarsal region, arch region and heel region, which could accurately extract the foot movement characteristics. Conclusions The peak plantar pressure is used to extract the characteristics of foot movement, which is divided into landing stage, whole foot contact stage, heel tiptoe stage and ground off stage.
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Objective To compare the differences in plantar kinetics between older male adults and young male adults during walking, and to explore the influences of aging on plantar kinetics. Methods The in-shoe plantar sensory measurement system was used to collect and compare left foot parameters of 13 older men and 14 young men during tandem walk, including contact time, beginning of contact in percentage of roll over process (%ROP), and end of contact in %ROP, peak pressure, instant of peak pressure in %ROP, maximum mean pressure, pressure-time integral, maximum force, instant of maximum force in %ROP, mean force and force-time integral. Results Beside media arch, the contact time on all regions of older men was longer, whereas, the beginning of contact in %ROP on lateral heel, lateral arch was greater, and the end of contact in %ROP on medial heel and 2nd-3rd metatarsal head was smaller compared with young men. The maximum force and mean force on the whole foot region, and the maximum mean pressure and maximum force on 2nd-3rd metatarsal head of older people were significantly lower; the pressure-time integral on the whole foot region, the 4th-5th metatarsal head, the 2nd -5th toes, and the force-time integral on the whole foot region, medial heel, lateral heel and 2nd -5th toes were significantly higher compared with young men. Conclusions During tandem walking, plantar fascia dysfunction might be one of the main reasons for the decline of postural control ability, and the contraction enhancement of flexor digitorum longus and flexor digitorum brevis could compensate for postural stability improvement in older men.
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Objective:To explore the mechanism of balance control after stroke by plantar pressure analysis. Methods:From July to December, 2019, twelve stroke subjects (stroke group) and 30 normal subjects (control group) were recruited in the rehabilitation department of our hospital. Both groups were measured plantar pressure in eyes open and closed conditions. The kinematic parameters, dynamic parameters, plantar pressure center (CoP), symmetry index (SI), symmetry angle (SA) and Romberg quotient (RQ) were calculated. Results:Compared with eyes open condition, the average Y and maximum swing of the control group increased significantly in eyes closed condition (P < 0.01); moreover, the ball length, average speed and maximum swing increased significantly in the stroke group (P <0.05). Compared with the control group, the area of the ellipse (|t| > 3.509, P < 0.001) and the average X (|Z|> 2.311, P < 0.05) significantly increased both in eyes open and closed condition, whereas the maximum swing (Z = -3.118, P < 0.01) increased significantly in eyes closed condition in the stroke group. The RQ of ball length was significantly more in the stroke group than in the control group (t = -3.570, P < 0.01). There was no significant difference in SI and SA of all parameters between the eyes open and closed condition in two groups (P > 0.05). Compared with the control group, load SI, overall load SI, forefoot load SI, area SI and forefoot area SI increased in both the eyes open and closed conditions in the stroke group (t > 2.344, P < 0.05), whereas load SA, overall load SA, forefoot load SA, area SA, forefoot area SA increased (|t|> 2.297, P < 0.05), hindfoot load SA increased only in eyes open condition (t = -2.485, P < 0.05), and hindfoot area SA increased only in eyes closed condition (t = -2.132, P < 0.05). In the control group, CoP was mainly distributed in the negative direction of Y axis when the eyes were open and closed, while CoP in the stroke group was relatively discrete, and the distribution on X axis was more obvious than that of the control group. Conclusion:The balance control of stroke patients might depend on visual compensation, and the plantar pressure analysis system could be used to evaluate the balance function in stroke patients.
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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.