Phys. Ther. Korea 2023; 30(4): 281-287
Published online November 20, 2023
https://doi.org/10.12674/ptk.2023.30.4.281
© Korean Research Society of Physical Therapy
Jinteak Kim1 , PT, MSc, Byeongsoo Kim1
, PT, PhD, Jongduk Choi2
, PT, PhD
1Department of Physical Therapy, Graduate School, Daejeon University, 2Department of Physical Therapy, College of Health and Medical Science, Daejeon University, Daejeon, Korea
Correspondence to: Jongduk Choi
E-mail: choidew@dju.kr
https://orcid.org/0000-0002-9663-4790
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Background: The flexible flatfoot is characterized by a flattening of the foot arch due to excessive bodyweight. The use of shoe insoles or taping methods has been identified as effective in realigning the navicular or calcaneus bones and addressing supination in pronated feet. Objects: This study aimed to analyze the difference between the arch taping attachment method, introduced in a previous study, and a novel taping method designed to provide support to the inner aspect of the heel bone in cases of flexible flatfoot.
Methods: A navicular drop test was performed to discriminate flexible flatfoot. To analyze the differences in pressure distribution during walking for each taping method, the subjects underwent testing in the barefoot state with no attachments. The procedure included a sequence of arch taping and heel taping. Subsequent analysis of pressure distribution during walking utilized the GaitRite® system (GAITRite Gold, CIR Systems Inc.).
Results: Arch taping and calcaneus taping significantly reduced the integrated pressure over time and peak pressure on the medial side of the midfoot for both feet compared to the barefoot state.
Conclusion: The findings of this study suggest that supporting the inside of the heel through calcaneus taping, without direct stimulation to the longitudinal arch and navicular bone, is an effective intervention for flexible flatfoot.
Keywords: Athletic tape, Calcaneus, Flatfoot, Foot orthoses, Tarsal bone
The diversity of the foot arch, consisting of the medial longitudinal, lateral longitudinal, and transverse arch, plays a crucial role in distributing body weight and reducing the stress on the foot, contributing to overall bodily protection [1]. Moreover, flatfoot is a condition characterized by the lowering or fattening of the medial longitudinal foot arch and can result from both congenital and acquired factors [2]. There are two forms of flatfoot, flexible flatfoot and static flatfoot. Flexible flatfoot arises from excessive bodyweight, leading to the flattening of the foot arch, whereas static flatfoot is a consequence of the normal arch structure, regardless of body weight. The exact cause of flat feet is not fully understood, and associated foot problems can affect the entire kinetic chain, causing issues in the knee joints, hip joints, and lower back [3]. Furthermore, the flatfoot may have detrimental effects on the musculoskeletal structure, potentially leading to disorders such as plantar fasciitis, hallux valgus, arthritis, joint fragility and developmental retardation. These issues arise from abnormal body weight distribution weakening postural stability and consequently cause misalignments in the body [4]. Flexible flatfoot is more likely to be acquired due to external factors, such as obesity or abnormal body weight [5].
Flexible flatfoot may be resolved by supportive intervention. Previous studies have identified the use of shoe insoles or taping methods to resolve the realignment of the navicular or calcaneus bones and correcting the pronated foot supination [6-8]. Specially designed shoe insoles show significant promise in providing support and facilitating recovery. However, the accessibility of these customized insole technologies is limited, especially among lower socioeconomic demographics, owing to their exorbitant manufacturing costs [9]. Generic insole materials, easily compressed by bodyweight, may prove ineffective. Hence, a specially formulated, weight-resistant material is essential to ensure effectiveness. Caution must be exercised to avoid deformed shoe insoles, as they can have negatively impact postural and walking sequences, leading to instability and potentially result in injuries and musculoskeletal disorders [10].
The taping method, recognized for its cost-effectiveness and customizable capabilities, presents certain limitations in achieving complete resolution of the foot arch due to a lack of padding. There are two types of tape employed, elastic [11] and non-elastic tape [12]. Non-elastic tape has been reported to have various effects, including the correction of flat feet, pain reduction, improvement of inner vertical arch height, and improvement of plantar pressure. However, the application of non-elastic tape can be challenging. The use of complex and multiple tape attachments may lead to issues such as discomfort in the feet and interference with sensory input from the feet [12]. Hence the elastic taping method is mostly utilized in clinical trials and research [13]. Previous studies have highlighted the efficacy of biomechanical tape, known for its strong tension in achieving effective arch taping [14].
Arch taping has demonstrated the capability to provide support to both the longitudinal and transverse arches while elevating the navicular bone [4]. However, despite being less challenging to apply than non-elastic tape, elastic tape still involves a cumbersome method of attachment. To identify additional taping methodologies, further scientific research must be conducted [15]. This study aimed to explore the differences between the arch taping methods identified in previous studies and the calcaneus taping method, which specifically supports the interior aspect of the calcaneus in cases of flexible flatfoot.
This study involved six young adults who met the inclusion criteria. Participants were required to be between 19 and 30 years old, exhibit flexible flatfoot, and provide their informed consent to participate in the study. This study was approved by the Daejeon University Ethics Committee (IRB no. 1040647-202203-HR-002-03). The exclusion criteria included individuals with static flatfoot, a history of musculoskeletal surgery, or a skin rash resulting from the use of any type of sports tape. A navicular drop test was conducted to discriminate flexible flatfoot (Figure 1) [16]. The characteristics of the subjects are outlined in Table 1.
Table 1 . General characteristics of subjects between groups (N = 6).
Variable | Subject | χ2 (p-value) |
---|---|---|
Sex (male/female) | 5/1 | 2.667 (0.10) |
Age (y) | 21.00 ± 1.73 | 0.000 (> 0.99) |
Height (cm) | 170.16 ± 5.87 | 0.667 (0.88) |
Weight (kg) | 71.33 ± 15.70 | 0.000 (> 0.99) |
Navicular drop (mm) | 7.83 ± 2.03 | 0.667 (0.88) |
Values are presented as number only or mean ± standard deviation..
The navicular drop test serves as a screening tool for flatfoot, providing a straightforward and highly reliable method for identifying flexible flatfoot. The test involves measuring the height of the navicular bone from the floor in a weight-bearing state, followed by measuring the height of the navicular in a relaxed position with no weight load. If the difference between the two measurements is 10 mm or more, it is classified as flexible flatfoot [17]. In this study, the navicular drop test was used to screen for flexible flatfoot in both feet.
This cross-sectional study observes the barefoot condition, as well as the application of arch taping foot and calcaneus taping (Figure 2) to analyze pressure distribution in each elastic taping method. Mechanotape® Sports tape (TR co., Ltd.) is an elastic tape made of nylon (80%) and spandex (20%). Additionally, this tape has a tensile strength of 310%, six times greater than that of Kinesio tape. Mechanotape® Sports tape is used to activate or inhibit exercise function by utilizing the characteristics of strong sweat absorption and strong tension [18]. In this study, Mechanotape® [19] served as a sports tape for foot correction in two biomechanical taping methods: arch taping [4] and calcaneus taping. Arch taping was applied vertically in relation to the navicular bone to lift the medial longitudinal and transverse arches of the foot. However, calcaneus taping was applied from underneath the lateral malleolus towards the rear calcaneus bone and extended to the medial malleolus. Elastic taping was performed by a physical therapist with over 10 years of clinical taping experience.
The GaitRite® system (GAITRite Gold, CIR Systems Inc.) was used to analyze the walking sequences and pressure distribution. The GaitRite® system has dimensions of 732 cm in length, 61 cm wide, equipped with 27,648 sensors, and operates at a sampling rate of 80 Hz [20]. The GaitRite® system displays 12 trapezoids of a footprint, with six located on the side of foot (1–6) and the remaining six situated inside the foot (7–12). Each trapezoid is equipped with a certain number of sensors, and the sensor activation sequence proceeds from the calcaneus bone to forefoot (Figure 3). The trapezoid is subdivided into the hindfoot, midfoot, and forefoot. The integrated pressure over time is defined as the product of time and pressure discerned by each cell’s sensor during walking, offering clinical insights into the specific foot region that experienced the highest pressure, represented as a percentage. The peak pressure is defined as the maximum pressure (%) observed during walking [21].
To minimize the impact of external factors and reduce the margin of error, participants were instructed to walk three times in the same direction, covering 5 m before the starting point of the GaitRite® system (Figure 4) and 5 m after the end point, on barefoot. Any datasets reflecting the participants’ unnatural movements were deemed unreliable and excluded from the analysis, prompting the need for experiment repetition. The mean value of the three experiments was then selected for analysis.
The data of the study was analyzed using IBM SPSS Statistics Window ver. 25.0 (IBM Co.). Descriptive statistics were employed to calculate the mean and the standard deviation of the general characteristics of the subjects, and the general characteristics were analyzed using chi-square test. To analyze the data, differences in each taping method were examined using the Kruskal-Wallis H test, a rank-based nonparametric test. Post hoc testing was performed using a Rank case and converted into a Rank variable and subsequently tested using One-way ANOVA. All statistical significance level was set to α = 0.05.
Table 1 presents the general characteristics of the participants. The results comparing the integrated pressure over time among the taping methods are shown in Tables 2 and 3. There were no significant differences observed in the integrated pressure over time between taping methods on the medial and lateral forefoot for both the right and left feet. However, significant differences (p < 0.003) were identified in the integrated pressure over time between taping methods on the medial midfoot for both the right and left feet. Post hoc testing further revealed that the integrated pressure over time on arch and calcaneus taped foot was significantly reduced (p < 0.05) compared to the barefoot condition. Conversely, no significant differences were found in the integrated pressure over time between taping methods on the lateral midfoot for the right and left feet, as well as the medial and lateral hindfoot for both right and left feet.
Table 2 . Comparison of integrated pressure over time between taping methods (right foot).
Variable | Barefoot (n = 6) | Arch taping (n = 6) | Calcaneus taping (n = 6) | χ2 | p-value |
---|---|---|---|---|---|
FFM P*t Rt. (%) | 21.78 ± 1.69 | 21.13 ± 3.30 | 20.83 ± 2.26 | 0.889 | 0.641 |
FFL P*t Rt. (%) | 21.30 ± 2.84 | 19.27 ± 1.34 | 18.90 ± 1.85 | 3.08 | 0.214 |
MFM P*t Rt. (%) | 7.27 ± 0.63 | 2.49 ± 1.39a | 3.49 ± 1.46a | 11.705 | 0.003* |
MFL P*t Rt. (%) | 13.43 ± 3.13 | 16.55 ± 2.77 | 17.92 ± 3.81 | 5.73 | 0.157 |
HFM P*t Rt. (%) | 16.00 ± 2.29 | 16.20 ± 2.21 | 15.90 ± 3.37 | 0.05 | 0.477 |
HFL P*t Rt. (%) | 14.18 ± 0.96 | 14.68 ± 1.84 | 15.17 ± 2.62 | 0.96 | 0.620 |
Values are presented as mean ± standard deviation. FFM, fore foot medial; P*t, integrated pressure over time; FFL, fore foot lateral; Rt., right; MFM, mid foot medial; MFL, mid foot lateral; HFM, hind foot medial; HFL, hind foot lateral. *p < 0.05. aSignificant difference (p < 0.05) from Barefoot..
Table 3 . Comparison of integrated pressure over time between taping methods (left foot).
Variable | Barefoot (n = 6) | Arch taping (n = 6) | Calcaneus taping (n = 6) | χ2 | p-value |
---|---|---|---|---|---|
FFM P*t Lt. (%) | 25.51 ± 6.90 | 22.80 ± 4.51 | 22.35 ± 3.81 | 0.74 | 0.692 |
FFL P*t Lt. (%) | 19.73 ± 2.60 | 17.39 ± 2.10 | 17.95 ± 2.81 | 2.25 | 0.325 |
MFM P*t Lt. (%) | 7.20 ± 0.64 | 2.46 ± 0.96a | 2.99 ± 0.97a | 11.875 | 0.003* |
MFL P*t Lt. (%) | 13.08 ± 3.56 | 17.15 ± 3.01 | 17.23 ± 3.76 | 5.07 | 0.079 |
HFM P*t Lt. (%) | 15.82 ± 2.23 | 15.15 ± 3.01 | 17.48 ± 2.62 | 1.56 | 0.459 |
HFL P*t Lt. (%) | 14.87 ± 2.34 | 15.87 ± 2.89 | 15.78 ± 16.61 | 2.21 | 0.330 |
Values are presented as mean ± standard deviation. FFM, fore foot medial; P*t, integrated pressure over time; FFL, fore foot lateral; Lt., left; MFM, mid foot medial; MFL, mid foot lateral; HFM, hind foot medial; HFL, hind foot lateral. *p < 0.05. aSignificant difference (p < 0.05) from Barefoot..
Tables 4 and 5 present the comparison of peak pressure between the taping methods. The peak pressure over time between taping methods on the medial and lateral forefoot for the right and left feet did not exhibit significant differences. However, significant differences (p < 0.003) were identified in the peak pressure between taping methods on the medial midfoot for the right and left feet. Subsequent post hoc testing revealed that peak pressure on the arch and calcaneus taped foot was significantly decreased (p < 0.05) compared to the barefoot condition. Conversely, the peak pressure between taping methods on the lateral midfoot for the right and left feet were not significantly different. Similarly, there were no significant differences in the peak pressure between taping methods on the medial and lateral hindfoot for both right and left feet.
Table 4 . Comparison of peak pressure between taping methods (right foot).
Variable | Barefoot (n = 6) | Arch taping (n = 6) | Calcaneus taping (n = 6) | χ2 | p-value |
---|---|---|---|---|---|
FFM Peak P Rt. (%) | 22.15 ± 4.15 | 22.03 ± 3.55 | 18.00 ± 1.81 | 4.464 | 0.107 |
FFL Peak P Rt. (%) | 19.27 ± 1.34 | 18.90 ± 1.85 | 18.90 ± 1.85 | 0.717 | 0.699 |
MFM Peak P Rt. (%) | 11.62 ± 1.04 | 7.45 ± 1.25a | 7.79 ± 1.60a | 11.453 | 0.003* |
MFL Peak P Rt. (%) | 17.57 ± 2.98 | 16.18 ± 3.29 | 16.18 ± 3.29 | 0.883 | 0.643 |
HFM Peak P Rt. (%) | 19.35 ± 2.14 | 19.65 ± 1.23 | 18.15 ± 3.24 | 0.222 | 0.595 |
HFL Peak P Rt. (%) | 17.00 ± 1.68 | 18.07 ± 2.26 | 18.07 ± 2.26 | 1.072 | 0.585 |
Values are presented as mean ± standard deviation. FFM, fore foot medial; Peak P, peak pressure; FFL, fore foot lateral; Rt., right; MFM, mid foot medial; MFL, mid foot lateral; HFM, hind foot medial; HFL, hind foot lateral. *p < 0.05. aSignificant difference (p < 0.05) from Barefoot..
Table 5 . Comparison of peak pressure between taping methods (left foot).
Variable | Barefoot (n = 6) | Arch taping (n = 6) | Calcaneus taping (n = 6) | χ2 | p-value |
---|---|---|---|---|---|
FFM Peak P Lt. (%) | 22.80 ± 4.51 | 2.48 ± 4.05 | 22.35 ± 3.81 | 0.038 | 0.981 |
FFL Peak P Lt. (%) | 17.35 ± 2.10 | 17.95 ± 2.81 | 17.95 ± 2.81 | 0.035 | 0.983 |
MFM Peak P Lt. (%) | 11.67 ± 0.95 | 6.85 ± 0.87a | 7.10 ± 1.16a | 11.474 | 0.003 |
MFL Peak P Lt. (%) | 16.58 ± 2.65 | 16.08 ± 3.69 | 16.08 ± 3.69 | 0.141 | 0.932 |
HFM Peak P Lt. (%) | 20.05 ± 2.61 | 19.63 ± 2.89 | 11.25 ± 1.69 | 11.380 | 0.878 |
HFL Peak P Lt. (%) | 18.25 ± 2.61 | 18.60 ± 2.36 | 18.60 ± 2.36 | 0.141 | 0.932 |
Values are presented as mean ± standard deviation. FFM, fore foot medial; Peak P, peak pressure; FFL, fore foot lateral; Lt., left; MFM, mid foot medial; MFL, mid foot lateral; HFM, hind foot medial; HFL, hind foot lateral. *p < 0.05. aSignificant difference (p < 0.05) from Barefoot..
This study provides the differences between walking barefoot and wearing footwear, employing the arch taping method to heighten the navicular bone, and utilizing the calcaneus taping method to support the inside of the heel bone. In comparing the integrated pressure over time between taping methods, both arch and calcaneus taped medial midfoot of the right and left feet, showed significant decrease compared to the barefoot condition. Previous studies have demonstrated the efficacy of the arch taping method, utilizing biomechanical elastic tape on flatfoot, in supporting the medial longitudinal arch, elevating the navicular bone, and enhancing lower quarter Y-balance ability and postural stability [4]. Additionally, earlier studies have validated that non-elastic low-dye taping has reduced the pressure on the lateral forefoot and provides support to the foot arch while standing [22]. Nevertheless, it lacks control over the neuromuscular system [7]. Notably, the integrated pressure over time between taping methods on medial and lateral forefoot, lateral midfoot, and medial and lateral hindfoot for both right and left feet did not show significant differences. This finding suggests that the reduction in integrated pressure over time on medial midfoot redistributes pressure to other parts of the foot.
The peak pressure on the arch and calcaneus taped medial midfoot for the right and left feet were observed to have been significantly reduced compared to the barefoot condition. This aligns with previous studies indicating that taping facilitates the support of the longitudinal arch and neutralization of the subtalar joint [11]. In contrast, no significant differences were observed in the peak pressure between taping methods on the medial hindfoot for the right foot and on the lateral side for both the right and left feet. Non-elastic calcaneus tape has been proven to be less effective in dispersing peak pressure on the forefoot. However, it reduces peak pressure on the medial and lateral hindfoot, suggesting its potential in alleviating pain associated with plantar fasciitis [23].
Foot taping serves as a primary intervention that can remarkably improve postural stability during walking by reducing the load on the tissues surrounding the foot and optimizing body weight distribution. Generally, taping methods that support the arch are considered uncomfortable due to impediments in movement caused by the strong tension of the tape [15]. Furthermore, in a previous study comparing various tapes, non-elastic tape was considered less comfortable than using elastic tape or walking barefoot [24]. The development of anatomical and biomechanical tape materials and technologies to reduce foot adduction aims to enhance comfort. Prioritizing comfort is crucial, especially when selecting a treatment to restrict hindfoot movement, given that the optimal amount of foot adduction has not been determined [18]. This study emphasizes the importance of individual reactions to taping methods before considering more restrictive interventions, such as splints [10].
The GaitRite® system was employed in this study to measure foot pressure distribution and surface contact mechanisms. This clinical tool proves resourceful as it eliminates the need for reflective markers and specific outfits. However, this study has identified a limitation as it exclusively focused on biomechanical aspects such as walking sequences and foot pressure. Further studies are warranted for other biomechanical neuromuscular systems to explore other variables such as lower quarter movement, foot mobility, muscle activation, and muscle fatigue. This study involved participants with an average age of 21 years old and may not be representative of all age groups. Additionally, participants exhibited other attributes, including the absence of prior foot injury symptoms, a lowered navicular bone by 7 mm, and a flexible flatfoot. Future studies must encompass a broader demographic and larger sample sizes including symptomatic subjects.
This study examined the differences between the integrated pressure and peak pressure over time by applying the arch taping method, which supports the existing medial longitudinal arch and raises the navicular bone, and calcaneus taping, aimed at realigning the medial calcaneus bone in cases of flexible flatfoot under barefoot conditions. The findings reveal a significant reduction in both integrated and peak pressure over time on the arch and calcaneus taped medial midfoot for both the right and left feet. Conversely, no significant reduction was observed on the lateral midfoot for the right and left feet, as well as the medial and lateral hindfoot for both right and left feet. This suggests that calcaneus taping can effectively alleviate the pressure-induced discomfort associated with arch taping, while still providing the same positive benefits.
None.
None to declare.
No potential conflicts of interest relevant to this article are reported.
Conceptualization: JC. Data curation: JK, BK. Formal analysis: JC. Investigation: JK, BK. Methodology: JK, BK. Supervision: JC. Visualization: JK, BK. Writing - original draft: JK, BK. Writing - review & editing: JC.
Phys. Ther. Korea 2023; 30(4): 281-287
Published online November 20, 2023 https://doi.org/10.12674/ptk.2023.30.4.281
Copyright © Korean Research Society of Physical Therapy.
Jinteak Kim1 , PT, MSc, Byeongsoo Kim1
, PT, PhD, Jongduk Choi2
, PT, PhD
1Department of Physical Therapy, Graduate School, Daejeon University, 2Department of Physical Therapy, College of Health and Medical Science, Daejeon University, Daejeon, Korea
Correspondence to:Jongduk Choi
E-mail: choidew@dju.kr
https://orcid.org/0000-0002-9663-4790
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Background: The flexible flatfoot is characterized by a flattening of the foot arch due to excessive bodyweight. The use of shoe insoles or taping methods has been identified as effective in realigning the navicular or calcaneus bones and addressing supination in pronated feet. Objects: This study aimed to analyze the difference between the arch taping attachment method, introduced in a previous study, and a novel taping method designed to provide support to the inner aspect of the heel bone in cases of flexible flatfoot.
Methods: A navicular drop test was performed to discriminate flexible flatfoot. To analyze the differences in pressure distribution during walking for each taping method, the subjects underwent testing in the barefoot state with no attachments. The procedure included a sequence of arch taping and heel taping. Subsequent analysis of pressure distribution during walking utilized the GaitRite® system (GAITRite Gold, CIR Systems Inc.).
Results: Arch taping and calcaneus taping significantly reduced the integrated pressure over time and peak pressure on the medial side of the midfoot for both feet compared to the barefoot state.
Conclusion: The findings of this study suggest that supporting the inside of the heel through calcaneus taping, without direct stimulation to the longitudinal arch and navicular bone, is an effective intervention for flexible flatfoot.
Keywords: Athletic tape, Calcaneus, Flatfoot, Foot orthoses, Tarsal bone
The diversity of the foot arch, consisting of the medial longitudinal, lateral longitudinal, and transverse arch, plays a crucial role in distributing body weight and reducing the stress on the foot, contributing to overall bodily protection [1]. Moreover, flatfoot is a condition characterized by the lowering or fattening of the medial longitudinal foot arch and can result from both congenital and acquired factors [2]. There are two forms of flatfoot, flexible flatfoot and static flatfoot. Flexible flatfoot arises from excessive bodyweight, leading to the flattening of the foot arch, whereas static flatfoot is a consequence of the normal arch structure, regardless of body weight. The exact cause of flat feet is not fully understood, and associated foot problems can affect the entire kinetic chain, causing issues in the knee joints, hip joints, and lower back [3]. Furthermore, the flatfoot may have detrimental effects on the musculoskeletal structure, potentially leading to disorders such as plantar fasciitis, hallux valgus, arthritis, joint fragility and developmental retardation. These issues arise from abnormal body weight distribution weakening postural stability and consequently cause misalignments in the body [4]. Flexible flatfoot is more likely to be acquired due to external factors, such as obesity or abnormal body weight [5].
Flexible flatfoot may be resolved by supportive intervention. Previous studies have identified the use of shoe insoles or taping methods to resolve the realignment of the navicular or calcaneus bones and correcting the pronated foot supination [6-8]. Specially designed shoe insoles show significant promise in providing support and facilitating recovery. However, the accessibility of these customized insole technologies is limited, especially among lower socioeconomic demographics, owing to their exorbitant manufacturing costs [9]. Generic insole materials, easily compressed by bodyweight, may prove ineffective. Hence, a specially formulated, weight-resistant material is essential to ensure effectiveness. Caution must be exercised to avoid deformed shoe insoles, as they can have negatively impact postural and walking sequences, leading to instability and potentially result in injuries and musculoskeletal disorders [10].
The taping method, recognized for its cost-effectiveness and customizable capabilities, presents certain limitations in achieving complete resolution of the foot arch due to a lack of padding. There are two types of tape employed, elastic [11] and non-elastic tape [12]. Non-elastic tape has been reported to have various effects, including the correction of flat feet, pain reduction, improvement of inner vertical arch height, and improvement of plantar pressure. However, the application of non-elastic tape can be challenging. The use of complex and multiple tape attachments may lead to issues such as discomfort in the feet and interference with sensory input from the feet [12]. Hence the elastic taping method is mostly utilized in clinical trials and research [13]. Previous studies have highlighted the efficacy of biomechanical tape, known for its strong tension in achieving effective arch taping [14].
Arch taping has demonstrated the capability to provide support to both the longitudinal and transverse arches while elevating the navicular bone [4]. However, despite being less challenging to apply than non-elastic tape, elastic tape still involves a cumbersome method of attachment. To identify additional taping methodologies, further scientific research must be conducted [15]. This study aimed to explore the differences between the arch taping methods identified in previous studies and the calcaneus taping method, which specifically supports the interior aspect of the calcaneus in cases of flexible flatfoot.
This study involved six young adults who met the inclusion criteria. Participants were required to be between 19 and 30 years old, exhibit flexible flatfoot, and provide their informed consent to participate in the study. This study was approved by the Daejeon University Ethics Committee (IRB no. 1040647-202203-HR-002-03). The exclusion criteria included individuals with static flatfoot, a history of musculoskeletal surgery, or a skin rash resulting from the use of any type of sports tape. A navicular drop test was conducted to discriminate flexible flatfoot (Figure 1) [16]. The characteristics of the subjects are outlined in Table 1.
Table 1 . General characteristics of subjects between groups (N = 6).
Variable | Subject | χ2 (p-value) |
---|---|---|
Sex (male/female) | 5/1 | 2.667 (0.10) |
Age (y) | 21.00 ± 1.73 | 0.000 (> 0.99) |
Height (cm) | 170.16 ± 5.87 | 0.667 (0.88) |
Weight (kg) | 71.33 ± 15.70 | 0.000 (> 0.99) |
Navicular drop (mm) | 7.83 ± 2.03 | 0.667 (0.88) |
Values are presented as number only or mean ± standard deviation..
The navicular drop test serves as a screening tool for flatfoot, providing a straightforward and highly reliable method for identifying flexible flatfoot. The test involves measuring the height of the navicular bone from the floor in a weight-bearing state, followed by measuring the height of the navicular in a relaxed position with no weight load. If the difference between the two measurements is 10 mm or more, it is classified as flexible flatfoot [17]. In this study, the navicular drop test was used to screen for flexible flatfoot in both feet.
This cross-sectional study observes the barefoot condition, as well as the application of arch taping foot and calcaneus taping (Figure 2) to analyze pressure distribution in each elastic taping method. Mechanotape® Sports tape (TR co., Ltd.) is an elastic tape made of nylon (80%) and spandex (20%). Additionally, this tape has a tensile strength of 310%, six times greater than that of Kinesio tape. Mechanotape® Sports tape is used to activate or inhibit exercise function by utilizing the characteristics of strong sweat absorption and strong tension [18]. In this study, Mechanotape® [19] served as a sports tape for foot correction in two biomechanical taping methods: arch taping [4] and calcaneus taping. Arch taping was applied vertically in relation to the navicular bone to lift the medial longitudinal and transverse arches of the foot. However, calcaneus taping was applied from underneath the lateral malleolus towards the rear calcaneus bone and extended to the medial malleolus. Elastic taping was performed by a physical therapist with over 10 years of clinical taping experience.
The GaitRite® system (GAITRite Gold, CIR Systems Inc.) was used to analyze the walking sequences and pressure distribution. The GaitRite® system has dimensions of 732 cm in length, 61 cm wide, equipped with 27,648 sensors, and operates at a sampling rate of 80 Hz [20]. The GaitRite® system displays 12 trapezoids of a footprint, with six located on the side of foot (1–6) and the remaining six situated inside the foot (7–12). Each trapezoid is equipped with a certain number of sensors, and the sensor activation sequence proceeds from the calcaneus bone to forefoot (Figure 3). The trapezoid is subdivided into the hindfoot, midfoot, and forefoot. The integrated pressure over time is defined as the product of time and pressure discerned by each cell’s sensor during walking, offering clinical insights into the specific foot region that experienced the highest pressure, represented as a percentage. The peak pressure is defined as the maximum pressure (%) observed during walking [21].
To minimize the impact of external factors and reduce the margin of error, participants were instructed to walk three times in the same direction, covering 5 m before the starting point of the GaitRite® system (Figure 4) and 5 m after the end point, on barefoot. Any datasets reflecting the participants’ unnatural movements were deemed unreliable and excluded from the analysis, prompting the need for experiment repetition. The mean value of the three experiments was then selected for analysis.
The data of the study was analyzed using IBM SPSS Statistics Window ver. 25.0 (IBM Co.). Descriptive statistics were employed to calculate the mean and the standard deviation of the general characteristics of the subjects, and the general characteristics were analyzed using chi-square test. To analyze the data, differences in each taping method were examined using the Kruskal-Wallis H test, a rank-based nonparametric test. Post hoc testing was performed using a Rank case and converted into a Rank variable and subsequently tested using One-way ANOVA. All statistical significance level was set to α = 0.05.
Table 1 presents the general characteristics of the participants. The results comparing the integrated pressure over time among the taping methods are shown in Tables 2 and 3. There were no significant differences observed in the integrated pressure over time between taping methods on the medial and lateral forefoot for both the right and left feet. However, significant differences (p < 0.003) were identified in the integrated pressure over time between taping methods on the medial midfoot for both the right and left feet. Post hoc testing further revealed that the integrated pressure over time on arch and calcaneus taped foot was significantly reduced (p < 0.05) compared to the barefoot condition. Conversely, no significant differences were found in the integrated pressure over time between taping methods on the lateral midfoot for the right and left feet, as well as the medial and lateral hindfoot for both right and left feet.
Table 2 . Comparison of integrated pressure over time between taping methods (right foot).
Variable | Barefoot (n = 6) | Arch taping (n = 6) | Calcaneus taping (n = 6) | χ2 | p-value |
---|---|---|---|---|---|
FFM P*t Rt. (%) | 21.78 ± 1.69 | 21.13 ± 3.30 | 20.83 ± 2.26 | 0.889 | 0.641 |
FFL P*t Rt. (%) | 21.30 ± 2.84 | 19.27 ± 1.34 | 18.90 ± 1.85 | 3.08 | 0.214 |
MFM P*t Rt. (%) | 7.27 ± 0.63 | 2.49 ± 1.39a | 3.49 ± 1.46a | 11.705 | 0.003* |
MFL P*t Rt. (%) | 13.43 ± 3.13 | 16.55 ± 2.77 | 17.92 ± 3.81 | 5.73 | 0.157 |
HFM P*t Rt. (%) | 16.00 ± 2.29 | 16.20 ± 2.21 | 15.90 ± 3.37 | 0.05 | 0.477 |
HFL P*t Rt. (%) | 14.18 ± 0.96 | 14.68 ± 1.84 | 15.17 ± 2.62 | 0.96 | 0.620 |
Values are presented as mean ± standard deviation. FFM, fore foot medial; P*t, integrated pressure over time; FFL, fore foot lateral; Rt., right; MFM, mid foot medial; MFL, mid foot lateral; HFM, hind foot medial; HFL, hind foot lateral. *p < 0.05. aSignificant difference (p < 0.05) from Barefoot..
Table 3 . Comparison of integrated pressure over time between taping methods (left foot).
Variable | Barefoot (n = 6) | Arch taping (n = 6) | Calcaneus taping (n = 6) | χ2 | p-value |
---|---|---|---|---|---|
FFM P*t Lt. (%) | 25.51 ± 6.90 | 22.80 ± 4.51 | 22.35 ± 3.81 | 0.74 | 0.692 |
FFL P*t Lt. (%) | 19.73 ± 2.60 | 17.39 ± 2.10 | 17.95 ± 2.81 | 2.25 | 0.325 |
MFM P*t Lt. (%) | 7.20 ± 0.64 | 2.46 ± 0.96a | 2.99 ± 0.97a | 11.875 | 0.003* |
MFL P*t Lt. (%) | 13.08 ± 3.56 | 17.15 ± 3.01 | 17.23 ± 3.76 | 5.07 | 0.079 |
HFM P*t Lt. (%) | 15.82 ± 2.23 | 15.15 ± 3.01 | 17.48 ± 2.62 | 1.56 | 0.459 |
HFL P*t Lt. (%) | 14.87 ± 2.34 | 15.87 ± 2.89 | 15.78 ± 16.61 | 2.21 | 0.330 |
Values are presented as mean ± standard deviation. FFM, fore foot medial; P*t, integrated pressure over time; FFL, fore foot lateral; Lt., left; MFM, mid foot medial; MFL, mid foot lateral; HFM, hind foot medial; HFL, hind foot lateral. *p < 0.05. aSignificant difference (p < 0.05) from Barefoot..
Tables 4 and 5 present the comparison of peak pressure between the taping methods. The peak pressure over time between taping methods on the medial and lateral forefoot for the right and left feet did not exhibit significant differences. However, significant differences (p < 0.003) were identified in the peak pressure between taping methods on the medial midfoot for the right and left feet. Subsequent post hoc testing revealed that peak pressure on the arch and calcaneus taped foot was significantly decreased (p < 0.05) compared to the barefoot condition. Conversely, the peak pressure between taping methods on the lateral midfoot for the right and left feet were not significantly different. Similarly, there were no significant differences in the peak pressure between taping methods on the medial and lateral hindfoot for both right and left feet.
Table 4 . Comparison of peak pressure between taping methods (right foot).
Variable | Barefoot (n = 6) | Arch taping (n = 6) | Calcaneus taping (n = 6) | χ2 | p-value |
---|---|---|---|---|---|
FFM Peak P Rt. (%) | 22.15 ± 4.15 | 22.03 ± 3.55 | 18.00 ± 1.81 | 4.464 | 0.107 |
FFL Peak P Rt. (%) | 19.27 ± 1.34 | 18.90 ± 1.85 | 18.90 ± 1.85 | 0.717 | 0.699 |
MFM Peak P Rt. (%) | 11.62 ± 1.04 | 7.45 ± 1.25a | 7.79 ± 1.60a | 11.453 | 0.003* |
MFL Peak P Rt. (%) | 17.57 ± 2.98 | 16.18 ± 3.29 | 16.18 ± 3.29 | 0.883 | 0.643 |
HFM Peak P Rt. (%) | 19.35 ± 2.14 | 19.65 ± 1.23 | 18.15 ± 3.24 | 0.222 | 0.595 |
HFL Peak P Rt. (%) | 17.00 ± 1.68 | 18.07 ± 2.26 | 18.07 ± 2.26 | 1.072 | 0.585 |
Values are presented as mean ± standard deviation. FFM, fore foot medial; Peak P, peak pressure; FFL, fore foot lateral; Rt., right; MFM, mid foot medial; MFL, mid foot lateral; HFM, hind foot medial; HFL, hind foot lateral. *p < 0.05. aSignificant difference (p < 0.05) from Barefoot..
Table 5 . Comparison of peak pressure between taping methods (left foot).
Variable | Barefoot (n = 6) | Arch taping (n = 6) | Calcaneus taping (n = 6) | χ2 | p-value |
---|---|---|---|---|---|
FFM Peak P Lt. (%) | 22.80 ± 4.51 | 2.48 ± 4.05 | 22.35 ± 3.81 | 0.038 | 0.981 |
FFL Peak P Lt. (%) | 17.35 ± 2.10 | 17.95 ± 2.81 | 17.95 ± 2.81 | 0.035 | 0.983 |
MFM Peak P Lt. (%) | 11.67 ± 0.95 | 6.85 ± 0.87a | 7.10 ± 1.16a | 11.474 | 0.003 |
MFL Peak P Lt. (%) | 16.58 ± 2.65 | 16.08 ± 3.69 | 16.08 ± 3.69 | 0.141 | 0.932 |
HFM Peak P Lt. (%) | 20.05 ± 2.61 | 19.63 ± 2.89 | 11.25 ± 1.69 | 11.380 | 0.878 |
HFL Peak P Lt. (%) | 18.25 ± 2.61 | 18.60 ± 2.36 | 18.60 ± 2.36 | 0.141 | 0.932 |
Values are presented as mean ± standard deviation. FFM, fore foot medial; Peak P, peak pressure; FFL, fore foot lateral; Lt., left; MFM, mid foot medial; MFL, mid foot lateral; HFM, hind foot medial; HFL, hind foot lateral. *p < 0.05. aSignificant difference (p < 0.05) from Barefoot..
This study provides the differences between walking barefoot and wearing footwear, employing the arch taping method to heighten the navicular bone, and utilizing the calcaneus taping method to support the inside of the heel bone. In comparing the integrated pressure over time between taping methods, both arch and calcaneus taped medial midfoot of the right and left feet, showed significant decrease compared to the barefoot condition. Previous studies have demonstrated the efficacy of the arch taping method, utilizing biomechanical elastic tape on flatfoot, in supporting the medial longitudinal arch, elevating the navicular bone, and enhancing lower quarter Y-balance ability and postural stability [4]. Additionally, earlier studies have validated that non-elastic low-dye taping has reduced the pressure on the lateral forefoot and provides support to the foot arch while standing [22]. Nevertheless, it lacks control over the neuromuscular system [7]. Notably, the integrated pressure over time between taping methods on medial and lateral forefoot, lateral midfoot, and medial and lateral hindfoot for both right and left feet did not show significant differences. This finding suggests that the reduction in integrated pressure over time on medial midfoot redistributes pressure to other parts of the foot.
The peak pressure on the arch and calcaneus taped medial midfoot for the right and left feet were observed to have been significantly reduced compared to the barefoot condition. This aligns with previous studies indicating that taping facilitates the support of the longitudinal arch and neutralization of the subtalar joint [11]. In contrast, no significant differences were observed in the peak pressure between taping methods on the medial hindfoot for the right foot and on the lateral side for both the right and left feet. Non-elastic calcaneus tape has been proven to be less effective in dispersing peak pressure on the forefoot. However, it reduces peak pressure on the medial and lateral hindfoot, suggesting its potential in alleviating pain associated with plantar fasciitis [23].
Foot taping serves as a primary intervention that can remarkably improve postural stability during walking by reducing the load on the tissues surrounding the foot and optimizing body weight distribution. Generally, taping methods that support the arch are considered uncomfortable due to impediments in movement caused by the strong tension of the tape [15]. Furthermore, in a previous study comparing various tapes, non-elastic tape was considered less comfortable than using elastic tape or walking barefoot [24]. The development of anatomical and biomechanical tape materials and technologies to reduce foot adduction aims to enhance comfort. Prioritizing comfort is crucial, especially when selecting a treatment to restrict hindfoot movement, given that the optimal amount of foot adduction has not been determined [18]. This study emphasizes the importance of individual reactions to taping methods before considering more restrictive interventions, such as splints [10].
The GaitRite® system was employed in this study to measure foot pressure distribution and surface contact mechanisms. This clinical tool proves resourceful as it eliminates the need for reflective markers and specific outfits. However, this study has identified a limitation as it exclusively focused on biomechanical aspects such as walking sequences and foot pressure. Further studies are warranted for other biomechanical neuromuscular systems to explore other variables such as lower quarter movement, foot mobility, muscle activation, and muscle fatigue. This study involved participants with an average age of 21 years old and may not be representative of all age groups. Additionally, participants exhibited other attributes, including the absence of prior foot injury symptoms, a lowered navicular bone by 7 mm, and a flexible flatfoot. Future studies must encompass a broader demographic and larger sample sizes including symptomatic subjects.
This study examined the differences between the integrated pressure and peak pressure over time by applying the arch taping method, which supports the existing medial longitudinal arch and raises the navicular bone, and calcaneus taping, aimed at realigning the medial calcaneus bone in cases of flexible flatfoot under barefoot conditions. The findings reveal a significant reduction in both integrated and peak pressure over time on the arch and calcaneus taped medial midfoot for both the right and left feet. Conversely, no significant reduction was observed on the lateral midfoot for the right and left feet, as well as the medial and lateral hindfoot for both right and left feet. This suggests that calcaneus taping can effectively alleviate the pressure-induced discomfort associated with arch taping, while still providing the same positive benefits.
None.
None to declare.
No potential conflicts of interest relevant to this article are reported.
Conceptualization: JC. Data curation: JK, BK. Formal analysis: JC. Investigation: JK, BK. Methodology: JK, BK. Supervision: JC. Visualization: JK, BK. Writing - original draft: JK, BK. Writing - review & editing: JC.
Table 1 . General characteristics of subjects between groups (N = 6).
Variable | Subject | χ2 (p-value) |
---|---|---|
Sex (male/female) | 5/1 | 2.667 (0.10) |
Age (y) | 21.00 ± 1.73 | 0.000 (> 0.99) |
Height (cm) | 170.16 ± 5.87 | 0.667 (0.88) |
Weight (kg) | 71.33 ± 15.70 | 0.000 (> 0.99) |
Navicular drop (mm) | 7.83 ± 2.03 | 0.667 (0.88) |
Values are presented as number only or mean ± standard deviation..
Table 2 . Comparison of integrated pressure over time between taping methods (right foot).
Variable | Barefoot (n = 6) | Arch taping (n = 6) | Calcaneus taping (n = 6) | χ2 | p-value |
---|---|---|---|---|---|
FFM P*t Rt. (%) | 21.78 ± 1.69 | 21.13 ± 3.30 | 20.83 ± 2.26 | 0.889 | 0.641 |
FFL P*t Rt. (%) | 21.30 ± 2.84 | 19.27 ± 1.34 | 18.90 ± 1.85 | 3.08 | 0.214 |
MFM P*t Rt. (%) | 7.27 ± 0.63 | 2.49 ± 1.39a | 3.49 ± 1.46a | 11.705 | 0.003* |
MFL P*t Rt. (%) | 13.43 ± 3.13 | 16.55 ± 2.77 | 17.92 ± 3.81 | 5.73 | 0.157 |
HFM P*t Rt. (%) | 16.00 ± 2.29 | 16.20 ± 2.21 | 15.90 ± 3.37 | 0.05 | 0.477 |
HFL P*t Rt. (%) | 14.18 ± 0.96 | 14.68 ± 1.84 | 15.17 ± 2.62 | 0.96 | 0.620 |
Values are presented as mean ± standard deviation. FFM, fore foot medial; P*t, integrated pressure over time; FFL, fore foot lateral; Rt., right; MFM, mid foot medial; MFL, mid foot lateral; HFM, hind foot medial; HFL, hind foot lateral. *p < 0.05. aSignificant difference (p < 0.05) from Barefoot..
Table 3 . Comparison of integrated pressure over time between taping methods (left foot).
Variable | Barefoot (n = 6) | Arch taping (n = 6) | Calcaneus taping (n = 6) | χ2 | p-value |
---|---|---|---|---|---|
FFM P*t Lt. (%) | 25.51 ± 6.90 | 22.80 ± 4.51 | 22.35 ± 3.81 | 0.74 | 0.692 |
FFL P*t Lt. (%) | 19.73 ± 2.60 | 17.39 ± 2.10 | 17.95 ± 2.81 | 2.25 | 0.325 |
MFM P*t Lt. (%) | 7.20 ± 0.64 | 2.46 ± 0.96a | 2.99 ± 0.97a | 11.875 | 0.003* |
MFL P*t Lt. (%) | 13.08 ± 3.56 | 17.15 ± 3.01 | 17.23 ± 3.76 | 5.07 | 0.079 |
HFM P*t Lt. (%) | 15.82 ± 2.23 | 15.15 ± 3.01 | 17.48 ± 2.62 | 1.56 | 0.459 |
HFL P*t Lt. (%) | 14.87 ± 2.34 | 15.87 ± 2.89 | 15.78 ± 16.61 | 2.21 | 0.330 |
Values are presented as mean ± standard deviation. FFM, fore foot medial; P*t, integrated pressure over time; FFL, fore foot lateral; Lt., left; MFM, mid foot medial; MFL, mid foot lateral; HFM, hind foot medial; HFL, hind foot lateral. *p < 0.05. aSignificant difference (p < 0.05) from Barefoot..
Table 4 . Comparison of peak pressure between taping methods (right foot).
Variable | Barefoot (n = 6) | Arch taping (n = 6) | Calcaneus taping (n = 6) | χ2 | p-value |
---|---|---|---|---|---|
FFM Peak P Rt. (%) | 22.15 ± 4.15 | 22.03 ± 3.55 | 18.00 ± 1.81 | 4.464 | 0.107 |
FFL Peak P Rt. (%) | 19.27 ± 1.34 | 18.90 ± 1.85 | 18.90 ± 1.85 | 0.717 | 0.699 |
MFM Peak P Rt. (%) | 11.62 ± 1.04 | 7.45 ± 1.25a | 7.79 ± 1.60a | 11.453 | 0.003* |
MFL Peak P Rt. (%) | 17.57 ± 2.98 | 16.18 ± 3.29 | 16.18 ± 3.29 | 0.883 | 0.643 |
HFM Peak P Rt. (%) | 19.35 ± 2.14 | 19.65 ± 1.23 | 18.15 ± 3.24 | 0.222 | 0.595 |
HFL Peak P Rt. (%) | 17.00 ± 1.68 | 18.07 ± 2.26 | 18.07 ± 2.26 | 1.072 | 0.585 |
Values are presented as mean ± standard deviation. FFM, fore foot medial; Peak P, peak pressure; FFL, fore foot lateral; Rt., right; MFM, mid foot medial; MFL, mid foot lateral; HFM, hind foot medial; HFL, hind foot lateral. *p < 0.05. aSignificant difference (p < 0.05) from Barefoot..
Table 5 . Comparison of peak pressure between taping methods (left foot).
Variable | Barefoot (n = 6) | Arch taping (n = 6) | Calcaneus taping (n = 6) | χ2 | p-value |
---|---|---|---|---|---|
FFM Peak P Lt. (%) | 22.80 ± 4.51 | 2.48 ± 4.05 | 22.35 ± 3.81 | 0.038 | 0.981 |
FFL Peak P Lt. (%) | 17.35 ± 2.10 | 17.95 ± 2.81 | 17.95 ± 2.81 | 0.035 | 0.983 |
MFM Peak P Lt. (%) | 11.67 ± 0.95 | 6.85 ± 0.87a | 7.10 ± 1.16a | 11.474 | 0.003 |
MFL Peak P Lt. (%) | 16.58 ± 2.65 | 16.08 ± 3.69 | 16.08 ± 3.69 | 0.141 | 0.932 |
HFM Peak P Lt. (%) | 20.05 ± 2.61 | 19.63 ± 2.89 | 11.25 ± 1.69 | 11.380 | 0.878 |
HFL Peak P Lt. (%) | 18.25 ± 2.61 | 18.60 ± 2.36 | 18.60 ± 2.36 | 0.141 | 0.932 |
Values are presented as mean ± standard deviation. FFM, fore foot medial; Peak P, peak pressure; FFL, fore foot lateral; Lt., left; MFM, mid foot medial; MFL, mid foot lateral; HFM, hind foot medial; HFL, hind foot lateral. *p < 0.05. aSignificant difference (p < 0.05) from Barefoot..