Plantar fasciitis is a common complaint, characterised by pain in the sole of the foot that is at its worst first thing in the morning or upon getting back up after a period of rest. Pain can be localised to the arch of the foot or under the heel.

Onset is often gradual with no particular cause noticed at the time.  Once entrenched, pain can be stubborn and frustrating, lasting many months.

The plantar fascia is a rugged, stretchy tendon structure of the anatomy of the foot that bridges the arch from the heel to the base of the toes to act like a spring. This serves to improve efficiency by returning elastic energy at the end of our step when we are walking or running.

Coming into summer I feel it is a good time to look at some of the potential factors that contribute to plantar fasciitis and heel pain.

Whilst working as a physiotherapist with the military population in Darwin I noticed some clinical patterns developing. It seemed that the incidence of onset was quite high in patients who had recently moved up to Darwin from the southern states.

This change of environment was associated with a change in lifestyle- both due to the different tropical climate and the style of the housing typical to Darwin. Essentially, patients would spend less time in supportive shoes (to which they had previously become accustomed), and more of this time was spent on hard concrete, tiled or paved surfaces. Carpet and timber floors were a rarity.

Symptoms would not commence immediately, but often after the first month or two. I believe it is no coincidence that this correlates with natural history of pathological failed tissue adaptations we see in tendinopathy.

In recent years I have relocated to open my own physiotherapy clinic, the PhysioStudio in East Maitland in the Hunter Valley, whereby I have observed another cyclical pattern -  presentations of plantar fasciitis and heel pain more commonly present through summer, probably as peoples’ footwear and lifestyles change due to the warmer weather.

Out of curiosity, I utilised the Google Trends function to explore this pattern. By investigating the search history of the term “plantar fasciitis” over the longer term in the United States there is a clear cycle of increased searching in the Northern summer months, and for August in particular.

The pattern is similar for “heel pain”, but by contrast not for other common injuries search terms such as “shoulder pain” or “impingement syndrome” or “rotator cuff tear”.

Based on this and our current understanding of tendon pathology I feel the best advice is to prevent the onset of plantar fasciitis.

Maintaining consistency is the key to preventing tendon injuries. Relative consistency of physical activity and lifestyle helps maintain tissue homeostasis. The likelihood is that a too rapid increase in the physical loads exerted on the plantar fascia exceed the tissue’s capacity to adapt and remodel in a sustainable way.

If these increased loads are maintained, they do not allow the sufficient time for tendon tissue to adapt healthily. This results in an upregulation of T- cell activity, expression of inflammatory cytokines, degradation of the collagen matrix, and pain.

It is understood that healthy tendon tissue adaptation takes at least 16 weeks in ideal circumstances.

It is not that summer is bad for our feet or unhealthy and it is equally untrue that a good pair of Havaianas at the beach or playing barefoot bowls on grass is dangerous. Rather that it is a significant change from the shape, structure, support and ramp angle of the footwear we more typically wear at other times of the year.

I’d suggest that, as much as wearing supportive shoes more in summer is a good idea, so too is it a good idea to moderate the use of footwear in the cooler months.

Similarly, if we are active outdoors during the warmer months we should aim to do better in maintaining our levels of physical activity through winter.

As with other tendon related injuries, physiotherapy advice can be very helpful. Education and exercise therapy have great evidence and should be the cornerstone of any treatment plan.

Specifically, isometric exercises progressing towards the inclusion of prescribed doses of eccentric loads can manipulate the cell activity within the plantar fascia and facilitate healthy tendon remodelling.

Building strength through the calf and foot, and leg system generally is also essential to allow the patient to walk and move without focusing excessive loads on passive structures such as the plantar fasciitis.

This together with careful ‘load management’ of the patient’s physical activity through their normal living day and sporting/recreational pursuits, will ensure improvement. Improvement is slow, and morning pain on rising to one's feet can take many months to resolve.

In the past cortisone injections, and more recently PRP protein injections and shock wave therapy have been used to treat plantar fasciitis. Unfortunately, strong evidence for these treatments is lacking, and this is probably because they do not directly influence the modelling and alignment of the collagen structure within the tissue.

About the Author:
Jon Davis is a Titled APA Sports Physiotherapist from East Maitland in NSW.
Before opening his PhysioStudio clinic he was a senior Sports Physiotherapist at the Australian Institute of Sport in Canberra where he worked under renowned tendon research publisher Craig Purdam. Jon has a special interest in overuse injuries including tendon and bone injuries. Jon was a physiotherapist at the 2014 Glasgow Commonwealth Games, 2018 Gold Coast Commonwealth Games and the 2014 Sochi Winter Paralympics.