Yim Physio Near Me: Flat feet vs. Neutral vs. High arch. How to do footprint yourself to classify your type of foot arch?

Wet footprint by water or sweat on the floor
(Ref: https://www.apexfoot.com/blog/)

I think, either you have been mentioned to someone flatfeet or you were asked about your flatfeet from someone. According to this conversation, it is discussed about abnormal foot posture and many bad conditions from the abnormal foot posture. Have you questioned this kind of conversation? Are you flatfeet? Does it always trouble your quality of life?

I always observe the foot arch characteristic as routine physical assessment in patients with foot pain, ankle pain, knee pain, low back pain, mid back pain, or neck pain. I realize that the foot is the base of every standing posture and activities, and is the origin of posture alignment.

Dropped foot arch develop poor posture and joint alignment (left)
(Ref: https://www.painfreeatsea.com/new-blog/)

The human feet are very complex having different components working together to create a complex flexible structure. The foot forms an important support for the body including support, balance, and mobility to the body. The foot arch is important in lifting the body weight and shock absorption by the ground reaction forces, which makes the arch a very important factor on walk and run safety, thus making direct influence on the biomechanics of an individual in case of any change.

There are two main functions for the foot during walking: a passive function which protects the human body from impact forces and an active function to transfer internal forces to the ground. The medial longitudinal arch (MLA) of the foot is the primary shock-absorbing structure particularly important for foot function .

Longitudinal arch load - shearing of the foot
(Ref: https://www.sciencedirect.com/science/article/pii/S0210123817300087)

Foot arch types can be classified by the Medial Longitudinal Arch (MLA) as high arch (cavus foot or oversupinate), normal arch (rectus foot) or low arch (planus or flat foot or overpronate). Both flat feet and high arch feet do not transmit forces efficiently and might lead to foot diseases.

My foot arch evaluation and posture is observation by vision mostly because some patients were obviously characteristic of heel and arch position. By the way, I cannot indicate them in some cases clearly. So, I have to use simple equipment and measure techniques for assessment that you can do yourself at home as well.

Ref: https://www.eastcoastpodiatry.sg/blog-post/

The technique to measure rear heel posture

VIDEO #1: We need a small goniometer or semicircular protractor, a small ruler, and a pen. Patients stand on the steps in order to easily see the heel and calf. Heel and calf are marked by a pen that the first mark is mid rear heel - the second mark is mid achilles tendon at malleolus level - the third mark is mid calf muscle. Then, I draw a straight line connecting all of them. After that, I use a goniometer or semicircular protractor to measure the angle.

“The normal range of rear heel posture is between 0 - 5 degrees”.

If the outcome is greater than 5 degrees either heel abduction or adduction, it will be indicated abnormal rear heel posture. Normally, foot arch type is related to rear heel posture. The flatfeet is always associated with an abducted heel that the high arch is opposite.

The footprint technique to classified foot arch type

VIDEO #2: Footprint: We need some black colored papers, powder, and a ruler. I started to put a lot of powder on a full plantar’s patient sitting position on the chair. Then I asked the patient to stand on the black paper for a while, and sit down to finish the footprint.

VIDEO #3: Calculation and analysis to classified: Then I selected one technique analysis to calculate the foot arch index, including:

(1) Arch (Clarke) angle: This is the angle between the line connecting the medial side-most points of the heel and metatarsal regions and the line connecting the lateral most point on the medial foot border to the medial-most point of the metatarsal region. perspective error.

Arch Clarke angle
(Ref: https://www.dovepress.com/)

The Clarke angle was calculated by Clarke index (ABC angle) which is Point A is the angle at the medial most margin of the forefoot, point B connects the medial side of the foot to the medial most part of the metatarsal region and point C at the medial most margin of the hindfoot.

The arches are defined based on scores of ABC angle; high arch (46 - 66 deg), normal arch (31 - 45 deg) and flat arch (10 - 30 deg).

(2) Chippaux-Smirak index: This is the ratio of the minimum width of the midfoot arch region to the maximum width of the forefoot region. They consist of a CD line at midfoot width and AB line at forefoot width. It is calculated by “(CD/AB) x 100” that the arches are categorized as high arch (10% - 24%), normal arch (25% - 45%) and flat arch (46% - 70%).

CD/AB ratio in Chippaux - Smirak index
(Ref: https://biomedical-engineering-online.biomedcentral.com/articles/10.1186/s12938-022-01021-7)

(3) Staheli index: This is the ratio of the minimum width of the midfoot arch region to the maximum width of the rearfoot region. It is calculated by “CD/EF” that line CD is the narrowest width of the midfoot and line EF is the wider zone of the hindfoot. The arches are defined as; high arch (0.1-0.4), normal arch (0.5-0.7) and flat arch (0.8-1.2).

CD/EF ratio in Staheli index
(Ref: https://biomedical-engineering-online.biomedcentral.com/articles/10.1186/s12938-022-01021-7)

(4) Arch length index: This is the ratio of the length of the line between the medial area -most points of the metatarsal and heel regions to the border length of the arch outline between these points.

Arch length index (Left)
(Ref: https://www.researchgate.net/figure/Definitions-of-foot-arch-parameters-a-arch-index-AI-measurement-from-the-footprint_fig1_318915682)

(5) Arch index: This is the ratio of the “area” of the middle third of the toeless footprint to the overall toeless footprint area. A line is drawn between the center point of the second toe and the posterior-most point on the heel. Two parallel lines perpendicular to this line are drawn to divide the toeless footprint area into equal thirds.

It is calculated by “(C+D+E)/D” that Line AB connects from the area of the forefoot at point of 2nd toe (toeless area) to the medial point of hindfoot. Line AB was divided into three equal areas of foot as C (covers most areas of forefoot), D (area of midfoot) and F (medial area of hindfoot). Arch index was calculated as the ratio between the sum of areas C, D and E over area D.

Arches are categorized based on scores obtained from the ratio of areas; high arch (0.11-0.20), normal arch (0.21-0.28) and flat arch (0.29-0.38).

Arch index (Right)
(Ref: https://www.researchgate.net/figure/Definitions-of-foot-arch-parameters-a-arch-index-AI-measurement-from-the-footprint_fig1_318915682)

(6) Footprint index: This is the ratio of the non-contact area to the contact areas of the toeless footprint. The non-contact area is the area between the medial borderline axis formed by the medial-most points of the metatarsal and heel regions of the footprint and the medial border of the footprint outline. The contact area is the area of the toeless footprint.

(7) Truncated arch index: This is the ratio of the non-contact area (the arch area) to the truncated footprint area. The non-contact area is the area between the medial border line and the medial footprint outline. The truncated footprint area is bounded by the area between the lines perpendicular to the medial borderline.

Middle lower demonstrates footprint index,
Right lower demonstrates Truncated arch index
(Ref: https://www.researchgate.net/figure/a-f-Graphical-illustrations-of-the-various-footprint-parameters-Arch-Clarke-angle-a_fig1_235779400)

In fact, there are several techniques for classification of foot type that are described in the literature, which measure the morphology and foot posture in a static position or during locomotion. Within the morphological classification techniques of the foot when standing are: visual inspection non-quantitative, anthropometric values, footprint parameters, radiographic evaluation, foot scan. Among these types of techniques there are pros and cons to all of them, as well as subjectivity and dependence of the experience of the evaluator (visual assessment techniques or by palpation) or expensive costs such as for the radiographic techniques.

Footprint scan
(Ref: https://jfootankleres.biomedcentral.com/)

Various techniques are used to determine these indices, including observation, foo printing, pressure mapping, radiographic imaging, ultrasound imaging, navicular drop, angle - related, foot function, etc.

High arched feet allow less motion and are identified as a risk factor for lateral ankle injury, stress fractures, and anterior knee pain. The most cases that I have seen was plantar fasciitis that was more than in flat feet.

While low arched feet have been shown to be at increased risk for medial tibial stress syndrome, knee pain, and other injuries involving the medial and soft tissue structures of the lower extremity. The most cases that I have seen complained about anterior knee pain and lateral knee pain which was ITB syndrome.

foot arch type and shoes wore
(Ref: https://www.solescience.ca/)

The survey studies tell us that excessive increase in weight bearing forces caused by obesity may adversely affect the foot arches. Elderly people have shown to have flatter, longer and wider feet than younger adults, and also older adults with osteoarthritis show greater dynamic loading of the midfoot when walking, due to the lower arch. A gender differences study showed that women have less arch stiffness than males and their arch is more flexible under both static and dynamic weight-bearing conditions.

It does not matter what factor you have, if you take care of your arch of foot well enough such as proper running shoes, proper insoles, proper sports & exercises, control BMI, etc., you will have a good quality of life.