扁平足成因可以是遺傳性、功能性(例如足部肌力不足或肌力不平衡)或由受傷(例如脛後肌腱失能 PTTD)引起。足弓下塌會令足部軟組織承受比正常更高張力，慢慢引致勞損問題 （例如足底筋膜炎）; 關節對位同時會受影響，長遠會導致關節變形。
扁平足的足弓下塌不單影響足部結構，還會引致連鎖反應。足旋前會令小腿內旋及膝蓋向內扭，以致膝關節對位不準，在跑步或步行時對關節做成壓力，長遠會引致膝關節勞損傷患。一個2011年進行的研究發現(Gross K. D., et al. 2011)，患有扁平足人士會有1.3倍機會患上膝痛及1.4倍機會患上膝軟骨受損。而肌肉繃緊或肌肉失衡(尤其臀部肌肉肌力不足及髖內收肌繃緊)往往會令情況惡化。
測試方法包括靜態及動態腳型分析，步姿分析及足底壓力測量 (plantar pressure mapping)。扁平足治療方法包括選配鞋墊作足弓承托，肌力及伸展訓練以協助正常關節對位。使用鞋墊的主要目的是把距下關節(subtalar joint)在站立時放回正中位置(neutral position)。藉由把距下關節放回正中位置，可以改善足部及膝關節對位和減低各關所所承受壓力，以達到預防傷患效果。
(此資訊由Mo Siu kwok會員撰寫)
Flat feet is a condition when the arches on the inside of the feet are lowered or even collapsed when you are standing.
The reasons of flat foot can be hereditary, functional (e.g. muscles weakness or imbalance) and injuries (e.g. Tibialis Posterior Dysfunction, PTTD).
With the collapse of the medial arch, the soft tissues in the foot are under greater tension, wear and tear conditions will develop gradually ; joint alignment is also affected and foot deformity may come next.
As the foot arch flattens, it doesn’t only affect the foot but also has a knock-on effect. Foot pronation causes internal rotation of the leg, making the knee to twist inwards and lead to misalignment of the knee joint. It causes stress to the knee joint while walking and running, contributing to wear and tear injuries.
A study conducted in 2011 shows that people with flat feet are 1.3 times more likely to have knee pain and 1.4 times more likely to have knee cartilage damage (Gross K. D., et al. 2011).
Podiatric assessments include static and dynamic foot profile assessment, gait analysis and plantar pressure mapping. Treatment options include insoles for arch support to prevent foot pronation, muscle training to help with facilitating normal joint alignment. The main purpose of the use of insoles is to put the subtalar joint back into its neutral position on the relax standing position. By putting the subtalar joint in the neutral position, we can reduce the excessive pronation during gait and therefore a more effective propulsion. Without excessive pronation during gait, less stress would be placed on the feet and thus the risks of injury.
It can be visualized by using a bisector line to the heel: when the subtalar joint is in its neutral position, the heel bisector line should be a vertical line; if the lines are leaning in, it means the feet are in a pronated position. We can see from the picture, the feet’s pronation are quite prominent on standing (more so on the left side) and the situation is improved with the the use of insoles.
Contact a podiatrist to arrange an assessment section.
(This article is written by member Mo Siu Kwok)
Gross K. D., et al. (2011)Association of Flat Feet With Knee Pain and Cartilage Damage in Older Adults. Arthritis Care and Research, 63(7), 937-944.
正常足弓 Normal Foot
使用鞋墊 Insoles Management