The plantar fascia is a thick fibrous connective tissue that spans a large portion of the under the surface of the foot. It runs from the heel to the base of the toes so to provide support the arch of the foot as the tissue undergoes tension when the foot is weight bearing. The plantar fascia also has a role in energy conservation during weight bearing tasks like walking and running. Finally, it also serves as a broad tissue attachment for other muscles in the foot

Plantar fasciitis is the most common cause of heel pain and accounts for up to 15% of all foot symptoms among adults. It is classified as an overuse injury, where in this case ‘overuse’ can result from various changes such as:

• Wearing shoes you haven’t worn before or a shoe you haven’t worn in a while i.e. thongs
• Increase in walking or running distance/time/speed
• Changes to your gait pattern i.e. a new running style or limping as a result of another injury
• Changes in the surface area you’re walking or exercising on

Plantar fasciitis has more recently been likened to other tendon related overuse injuries, despite not being a tendon. This similarity has been drawn due to a similar structure and function. These injuries occur over time as we continue to load these tissues without allowing for adequate rest and recovery time between bouts of exercise, or if the exercise intensity/duration is too greater increase. Over time the structural make-up of the plantar fascia changes and as a result, the ability of the tissue to absorb load reduces and subsequent pain instills.

In most cases, plantar fasciitis presents as a gradual onset of the heel or plantar foot pain that is generally worse during the first steps in the morning or after periods of inactivity. The pain tends to improve with activity throughout the day and then worsens towards the end of the day with increased weight-bearing tasks, though this presentation can vary throughout cases.

Plantar fasciitis is defined as an overuse injury (Lemont et al., 2003). Prior to the onset of symptoms increased amount of weight-bearing activity, such as walking and running, can cause an overuse response within the plantar fascia that progresses to generate degenerative changes causing the symptoms of plantar fasciitis. Overuse can come in many forms, not just increased load-bearing activity, and in the case of plantar fasciitis changes in footwear or exercise surface can alter the dynamics of plantar foot tissue, enough to generate an overuse response (Cole, Seto, & Gazewood, 2005).

Imaging is limited in its ability to diagnose plantar fasciitis though it may be utilised in order to rule out other possible conditions. Calcaneal stress fractures and other bony lesions can mimic the clinical symptoms of plantar fasciitis and may require MR imaging or a bone scan to be ruled out.

A tear of the plantar fascia can present with similar symptoms however the onset of pain is resultant of a mechanism or sudden onset and may cause an inability to weight-bear after the initial injury and with other physical activity.

Tarsal tunnel syndrome or compression of the medial calcaneal branch of the posterior tibial nerve can cause symptoms of heel and plantar foot pain, though the type of pain is usually of a burning nature. Symptoms involving neurological tissue may also present with pain that radiates up the leg. There will also be notable tenderness over the medial aspect of the heel or inferior to the medial part of the ankle.