Journal of the Anatomical Society of India

: 2021  |  Volume : 70  |  Issue : 1  |  Page : 48--51

Analysis of vertical forces in children with down's syndrome by using emed® capacitance-based pressure platform

Venkata Nagaraj Kakaraparthi1, Vamsi Krishna Gannamaneni2, Lalitha Kakaraparthi3,  
1 Department of Medical Rehabilitation Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia
2 Department of Medical Rehabilitation Sciences, College of Applied Medical Sciences, Hail University, Hail, Saudi Arabia
3 Department of Physiotherapy, Parul University, Vadodara, Gujarat, India

Correspondence Address:
Dr. Venkata Nagaraj Kakaraparthi
Department of Medical Rehabilitation (Physical Therapy), College of Applied Medical Sciences, King Khalid University, C/3/139, Abha, Guraiger Campus
Saudi Arabia


Introduction: This study aimed to analyze the vertical forces functioning under the plantar surface of the feet in children with and without Down's syndrome (DS) during walking using a capacitance-based pressure platform (emed®). Material and Methods: This is an observational study on 10 individuals with DS, (Group I) and 10 children without DS (Group II), aged 8–15 years. Both the groups were evaluated while standing on a capacitance-based pressure platform. Maximum force, peak pressure, contact time, and contact area parameters were assessed for both right and left foot. In this study, we assessed and compared these parameters in both the groups. Results: The results showed that the foot-ground interaction forces varied between the two groups. In particular, parameters such as maximum force, peak pressure, and contact area were statistically significant, where no significant difference was found concerning the contact time parameter. Discussion and Conclusion: The capacitance-based pressure platform (emed®) must be considered an essential evaluation tool for assessing vertical forces associated with children with DS. Thus, organizing regular monitoring of foot-ground reaction forces during the early years in DS children is suggested to prevent potential complications associated and decrease the probability of mobility impairments in adulthood.

How to cite this article:
Kakaraparthi VN, Gannamaneni VK, Kakaraparthi L. Analysis of vertical forces in children with down's syndrome by using emed® capacitance-based pressure platform.J Anat Soc India 2021;70:48-51

How to cite this URL:
Kakaraparthi VN, Gannamaneni VK, Kakaraparthi L. Analysis of vertical forces in children with down's syndrome by using emed® capacitance-based pressure platform. J Anat Soc India [serial online] 2021 [cited 2021 May 11 ];70:48-51
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Full Text


Down syndrome (DS) is a chromosomal disorder mainly produced by full trisomy of chromosome 21.[1] In DS, an increased occurrence of musculoskeletal problems were seen. The most common problems are of less severity. They commonly involve the lower extremities, such as hip disorders, patellofemoral instability, hallux valgus, metatarsus primus varus (MPV), and pes planus/flat foot.[2],[3] These insignificant musculoskeletal problems are frequently misjudged and neglected due to the mere presence of more serious associated pathologies in DS. Early diagnosis of these problems by proper clinical evaluation, radiographic evaluation, podiatric evaluation with barometric evaluation is necessary to measure the extent of the deformity.[3],[4] These evaluation procedures provide information about the functional limitations of activities of daily living in children with DS. Furthermore, it has been noticed that children with DS demonstrate impaired balance, weight bearing functions, and a distinctive foot ground contact pattern, which has been characterized by larger midfoot and decreased forefoot interaction areas and enhanced contact pressure areas in the midfoot and the forefoot.[5]

The necessity for careful examination and assessment of foot pressures during childhood may help to decrease the risk of impaired mobility in adulthood and minimize the potential effects in DS.[6] Only a limited studies has been done in children with DS, to evaluate the foot-ground interaction forces. Concolino et al. evaluated the plantar pressure patterns during DS children's static and dynamic conditions and revealed a substantially altered foot function and altered rearfoot–forefoot surface ratio values.[3] Pau et al. evaluated the foot-ground parameters in children with DS. They demonstrated the high prevalence of flat feet in these children, which has been associated with the existence of more significant contact pressures in midfoot and forefoot.[5] Galli et al. focused on foot rotation graph using pressure-sensitive mat, and suggested that the existence of flatfoot in children with DS may cause more extra rotation of their feet than the children devoid of flat foot.[7] Prasher et al. explored the foot pressure points by using Harris mat technique, in children with DS and found high pressure points, specifically at the areas of callus formation and verrucae.[8] However, the absence of early identification methods can cause severe biomechanical and postural problems in children with DS.

Hence, the present study aimed to evaluate the vertical forces acting under the plantar surface of the feet in children with and without DS during walking and to assess the progress of contact area and pressure distribution by using capacitance-based pressure platform (emed®). We strongly believe these findings can enhance the current approaches and treatment protocols to podiatric management of children with DS.

 Material and Methods


Three schools (one special and two public) in the Hail region of Kingdom of Saudi Arabia have participated in the study. Ten children with DS, with a mean age of 10.1 ± 1.6 years (age range 8–14 years) who were characterized by abnormality in trisomy 21 chromosome were assigned in Group I. Inclusion criteria in this group (1) age 8–14 years, (2) low-medium intelligence quotient, (3) no history of surgery. Exclusion criteria (1) children who were unable to understand the researcher's instructions to complete the procedure. Additionally, to compare the data obtained, a control group consists of ten children without DS, with a mean age of 10.3 ± 1.8 years (age range 8–14 years) was allocated to Group II. Inclusion criteria in this group (1) age 8–14 years (2) to complete the procedure without any assistance. Exclusion criteria (1) children known to the researchers (2) history of spine, upper limb, or lower-limb surgeries (3) history of musculoskeletal or cardiovascular disorders. Data were assessed for both right and left limbs. All the required permissions were taken from the schools for performing the study. Before executing the evaluation, the examiner described this research's procedure and purpose of this research to all the children. The study was approved by the ethical committee of the institute and informed consent was attained from the parents of the children enrolled in the study.


Demographic data (age, gender) and anthropometric measures, which include height (meters), weight (kg), and body mass index (BMI) (kg/m2), were evaluated for all children with a standard procedure. All the children underwent a general examination of the feet and podiatric assessment and evaluation by using the emed analysis system.

General observation of feet

Clinical examination includes appearance of both the feet-hallux valgus, hallux varus, abnormalities of toes – MPV, syndactyly, clinodactyly of fifth toe, rotation of feet – abduction/adduction or plantar flexion/dorsiflexion of feet and presence of any abnormal arches of the feet.

Podiatric assessment

Podiatric examination and evaluation were assessed by one of the researchers. The emed® analysis is a user-friendly device (emed® q100, 100 Hz, 4 sensors/cm2-resolution, 475 mm × 320 mm-sensor area, pressure range - 10–1270 kPa, pressure threshold-10kPa) used in this study to evaluate the pressure distribution under the feet during walking.[9] It has pressure plates having calibrated capacitive sensors and two electrically conducting surfaces that were separated by rubber. It starts recording the data automatically when the children's foot contact the platform and[10] It also demonstrated good test-retest reliability (interclass coefficient >0.8) during walking on the platform.[11] Studies also showed less error within sessions and between days and measures the foot pressure accurately during walking.[9],[12]

After a brief demonstration of the procedure, the children were asked to walk barefoot on the emed® analysis platform at an average walking speed. Ten trails were performed for the affected foot. To minimize the fatigue in children, a rest period of 5 min was given for every attempt. All the participants were asked to take four to five steps before starting on the platform. The children were instructed to mainly focus on the rounded sticker attached in both directions during walking. The researcher recorded the mean of ten trails for further evaluation. Trials fluctuating ≤10% in time were believed to be acceptable. If any child foot is placed near to or on the pressure platform's edges the trail was repeated [Figure 1].[13]{Figure 1}

Data analysis

In the present study, we utilized Novel's project software (Novel, Munich, Germany) to examine the foot plantar pressure data by applying a twelve-region mask under the foot. For analysis and to compare with the normal foot, the foot was divided into ten regions-hindfoot, midfoot, 1st metatarsal, 2nd metatarsal, 3rd metatarsal, 4th metatarsal, 5th metatarsal, 1st toe, 2nd toe and 3rd, 4th and 5th toes (as one region). We also assessed the Hallux angle and arch index for all children. The following plantar pressure factors were calculated: Maximum force (N), peak pressure (kPa), contact time (% range of pressure (ROP)), and contact area (cm2). All these parameters were computed from the maximum pressure throughout the stance phase plot for the entire foot contact region (total) and the 10 regions of the foot in children with and without DS.[14]

SPSS software (version 21.0 for Windows; SPSS, Inc., Chicago, IL, USA) was used to perform the statistical analyses. Descriptive statistics of the mean ± standard deviation for each plantar pressure parameter for all ten regions were evaluated. To compare the variances in maximum force, peak pressure, contact time, and contact area between two groups, an independent t-test was used.


The anthropometric characteristics for all subjects are presented in [Table 1], with a mean height of 1.27 ± 1.66 m for Group I and 1.47±0.077 m for Group II, a mean weight of 34.73 ± 11.97 kg for Group I and 44.55 ± 10.34 kg for Group II, and mean BMI of 20.89 ± 4.62 kg/m2 for Group I and 20.44 ± 3.59 kg/m2 for Group II. No significant differences were found in age, height, and BMI, except for weight (P < 0.001).{Table 1}

[Supplementary Table 1]a and [Supplementary Table 1]b summarizes the amount of maximum force concerning to right and left foot in both groups. However, regarding maximum force, the right foot group (P = 0.009) showed a nonsignificant effect, while the left foot group showed a significant (P < 0.001) effect in the study.[INLINE:1]

[Supplementary Table 2]a and [Supplementary Table 2]b summarizes the peak pressure concerning right and left foot in both groups. Both the foot groups exhibited (P < 0.001) a significant effect in the study about peak pressure. In contrast, the DS group showed more peak pressure in all ten regions than the non-DS group.[INLINE:2]

[Supplementary Table 3]a and [Supplementary Table 3]b summarizes the contact time in relation to right and left foot in both groups. However, regarding contact time, the right foot group (P = 0.58) showed a nonsignificant effect, while the left foot group showed a statistically significant (P < 0.001) effect in the study. The DS group exhibited more contact time values than the non-DS group in this study.[INLINE:3]

[Supplementary Table 4]a and [Supplementary Table 4]b summarizes the contact area in relation to right and left foot in both groups. However, about the contact area, both the foot groups exhibited (P < 0.001) a substantial statistical effect in the study.[INLINE:4]


This study aimed to assess the vertical forces functioning under the plantar surface among the children with and without DS during walking by using capacitance-based pressure platform (emed®).

This study also demonstrated a variance in maximum force, peak pressure, contact time, and contact area among children with DS compared with non-DS children. These results emphasize the need to examine the foot pressure in children with DS more carefully and prevent further complications. Our study reported an increased amount of forces and peak pressures in DS children, particularly in the mid-foot;[15],[16],[17] these observations agree with those of previous studies.

In comparison to normal children, most DS children showed orthopedic abnormalities that mostly involve the lower extremities. The negligence of the anomalies adversely affects the motor skills of these children.[8] For this purpose, we firmly believe that during the assessment of children with DS, a proper podiatric assessment can diagnose such problems and improve the quality of life in these children.

However, to our expertise, no study has assessed both the force and contact parameters in children with DS. Concerning maximum force (N), the force applied on the pressure platform by normal children was more than the children with DS, in relative to peak pressure (kPa), more pressure displayed by children with DS, in relation to contact time, no significant differences were found between these two groups of children, and lastly, concerning contact area (cm2), children with DS showed less amount of contact areas when compared to normal children. The differences in these parameters were supported by variances in DS children's gait parameters compared to typical children.[18],[19]

In the present study, a significant (P < 0.001) difference was observed in weight between the children with and without DS and considered one of the factors that explain the variance in these parameters, which further affect the gait parameters in children with DS.[20],[21],[22]

The present study has some limitations. First, it was conducted only on small sample size. Second, our results only apply to dynamic foot assessment using a capacitance-based pressure platform (emed®), because other clinical measures with dynamic foot evaluation during walking were not considered. Third, these tests can be done with different age groups in children with and without DS. Besides, more studies were recommended to overcome all these limitations.


The present study found exclusive findings in relation to maximum force, peak pressure, contact time, and contact area in DS children. This study also emphasizes the need for podiatrists and practitioners engaged with care of DS children. Although the variances were found in these parameters, further studies with a larger sample are essential to replicate the current findings.


The authors declare that they have no conflict of interest.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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