Flip flops, sandals……and Plantarfasciitis!


The current spell of hot weather leads us all to open our summer wardrobes and don our light clothes that we only manage to wear for such a short period of our calendar year.

Our heavy boots and sturdy shoes become replaced by light, breathable footwear allowing airflow to our sweltering feet. But sometimes our bodies are not necessary ready for this drastic change of foot attire.

The amount of support a boot or brogue shoe offers a foot is very different to the near non- existent support of a flip flop and delicate sandal. So what happens when our feet are faced with this footwear revolution!

Two important compensations are regularly seen in clinic when we observe someone walking in “flimsy footwear”.

The first happens around the horizontal axis of the foot. If you look down at your exposed foot, you have ‘hopefully’ a visible inner or “medial” arch. Structured shoes have sturdy heel cups that hold our heel in a supported position, and enclosure offered by the shoes ”upper”, with tightly tied laces, provide lateral stability for our midfoot. Take away the heel and forefoot support and in some cases the foot will start to roll inwardly. This motion is called Pronation and can lead to the medial “inner” arch to flatten. Our feet have to pronate to some degree in normal walking however released of the shackles of supportive heel cups and tied laces our feet can then excessively pronate and roll inwards.

The second compensation occurs around the vertical axis of the foot. Many of our non-summer shoes have heels of varying sizes. All of a sudden we change to flip flops and sandals and the shoe heel which lifted our heel off the ground has disappeared. To make contact with the ground the heel is now more dropped and flatter compared to our heeled shoes, so the hinge joint in the centre of our ankle has to bend more. Such a relative increase in ankle bending increases forces under the foot if individuals are very mobile. However, those with stiff ankles/tight calf muscles will be unable to bend more in the pivot of the ankle joint, therefore the body will always try and cheat or compensate for any restriction. One very common way is to excessively roll or pronate the foot again as in our first example and loose/roll on the inner arch.

So what are the main implications for this excessive rolling/pronation of the foot and increased ankle bend we have just out-lined.

Under our foot we all have a structure called the Plantarfascia. It attaches from the heel bone and extends and fans out across the foot to the base of our toes. In normal walking as we lift out heel and bend our big toe, the Plantarfascia naturally tightens, pulling our heel in and providing a rigid/stable base for the foot to become a rigid lever of which muscles can push against and propel us forward.

During the winter and spring months in our supportive shoes our Plantarfascia has become accustomed to the everyday forces it has to deal with. Now the hot weather arrives and we crack open the flip flops – all the previous mentioned changes in foot position occurs. This can lead to a significant increase in the load/force being transmitted through the Plantarfascia as the less supportive shoes cannot take on some of this force or shield our foot from the load.

When any ligament/tendon tissue if faced with an increasing force it has two options. Firstly, adapt to the load by slowly changing its structure so it can cope with the increasing force. This is the process behind any sort of adoptive training. Or secondly it can fail to adapt, become overloaded, the tissue then changes structure in a negative way, becomes damaged and inflamed. This can set off a number of attempted healing processes which sometimes can fail and lead to chronic ongoing pain in the underside of the heel, which we know as Plantarfasciitis.

The above process is one of the most common scenarios we see in Plantarfasciitis occurring in the summer.

With this in mind, what can you do to help this? As with all things, prevention is always better than the cure. When thinking of taking out the sandals from the back of the cupboard in late spring don’t go mad! Perhaps wear the flip flops for a day or few hours and then go back to your trainers/shoes. After a couple of weeks the Plantarfascia can slowly adapt to the change in forces and get stronger. Also wear flip flops or sandals with more shaped soles or higher heel if you have suffered from Planatafascia issues before.

If you do develop Plantarfasciitis, in its initial stages it is inflammatory so ice and non steroidal medication can help, as well as stretching the calf muscle.

If symptoms persist consider seeking help from a Physiotherapist. A detailed examination can highlight any biomechanical problems you may have in your foot, lower and upper leg and even hip and pelvis. These may contribute to excessive stress on the Plantarfascia. As I said before the Plantarfascia like other ligaments and tendons is an adaptive tissue. Your physiotherapist can construct an exercise regime tailored to you which will progressively strengthen the Plantarfascia so it can cope with the loads being placed on it. Other adjuncts, such as taping help in the early stages to take pressure off the Plantarfascia and decrease pain. Orthotics and heel raised can also do this.

Summer is a great time to enjoy the warm weather but always be aware of sudden changes in footwear if you have had foot/heel problems before.