Journal List > J Korean Foot Ankle Soc > v.24(1) > 1144008

J Korean Foot Ankle Soc. 2020 Mar;24(1):14-18. Korean.
Published online Mar 13, 2020.
Copyright © 2020 Korean Foot and Ankle Society
Correlation between Chronic Ankle Instability and Center of Pressure Using Pedobrarograph
Eun Soo Park, Sang Gyo Seo,* and Ho Seong Lee
Department of Orthopedic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
*Department of Orthopedic Surgery, SNU Seoul Hospital, Seoul, Korea.

Corresponding Author: Sang Gyo Seo. Department of Orthopedic Surgery, SNU Seoul Hospital, 237 Gonghang-daero, Gangseo-gu, Seoul 07803, Korea. Tel: 82-2-333-5151, Fax: 82-2-333-5152, Email:
Received Mar 04, 2019; Revised Feb 08, 2020; Accepted Feb 10, 2020.

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.



Chronic ankle instability is a very common abnormality of the ankle, but there is still controversy regarding its evaluation criteria. The stress view has difficulties in reflecting the patient's symptoms and treatment progress. Therefore, this study examined the relationship between the center of pressure (COP) measured by a pedobarograph and the symptoms of the patient.

Materials and Methods

Thirty patients with chronic ankle instability from February to August 2018 were included. Each patient was surveyed with the foot and ankle outcome score (FAOS). The COP was measured with a foot pressure scanner, and the travel distance and ellipse area of the COP were calculated. Each patient was measured on one foot and on two feet with his or her eyes closed and open. The relationship between the COP measurement and FAOS score was analyzed using the Pearson correlation coefficient.


The participants were consisted of 21 male and nine female, with a mean age of 30 years, mean weight of 72 kg, and mean foot size of 259 mm. With the eyes open, the correlation coefficient between the FAOS and travel distance of the affected side was −0.394 (p<0.05) and that between the FAOS and the ellipse area of the affected side was −0.425 (p<0.05). On the other hand, no significant correlations were found between the travel distance and ellipse area of the affected side when patients closed their eyes.


Measurement of the COP using foot pressure scanner could evaluate objectively patients with chronic ankle instability, with measurements in patients with their eyes open being more significant. Based on the findings of this study, an analysis of the COP with the patients with their eyes open and standing on one foot may help determine the management strategy and assess the progress of the patients.

Keywords: Chronic ankle instability; Pedobarograph; Balance


Figure 1
Measuring center of pressure (open eyes).
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Figure 2
Measuring center of pressure (closed eyes).
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Figure 3
Male (64 kg, 20 years old), shoes size 265 mm, center of pressure (open eyes) was examined during single leg standing for 30 seconds (short arrow : traveled distance, long arrow : ellipse area).
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Figure 4
Correlation between center of pressure and FAOS. COP: center of pressure, QOL: quality of life, FAOS: foot and ankle outcome score.
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Table 1
Demographic Factors
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Table 2
Result of the Affected Side Examined with Open Eyes (Pearson Correlation Coefficients)
Click for larger image


Financial support:None.

Conflict of interest:None.

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