Pain under the foot (plantar fasciitis)

Plantar fasciitis causes severe burning or stabbing pain under the heel or foot. It can also feel as if you’re walking on broken glass. The following is typical in plantar fasciitis:

• Extreme pain in the sole of the foot when you take your first steps in the morning or after you’ve been sitting for a long time.
• The pain subsides once you’ve walked around for a while. But it can come back again after very strenuous days or activities – for example, if you spend a long time in a standing position or carrying something heavy.

Plantar fasciitis can affect one foot or both feet at the same time. In roughly one third of cases, the plantar fascia in both feet are inflamed.

The plantar fascia starts beneath the heel bone and extends into the toes. It stabilizes the foot during movement and has a cushioning effect. During the heel-to-toe rolling movement you make with each step, the plantar fascia tissue tightens so that it can support the arch of your foot. During this movement, the strain at the point where the tissue attaches to the heel is particularly high.

If it becomes too much, small tears occur around the attachment point. These can become irritated and lead to inflammation. It is thought that this overload and irritation is caused by a combination of factors coming together.

Heavy, persistent or unusual strain on the heel or foot increases the risk of plantar fasciitis. Because of this, it’s particularly common in people who do a lot of sports: people who often run long distances, play football or dance, for example. People who return to sport too quickly and do too much after a break are also at risk. Another risk factor is standing for long periods of time – as is standard practice for sales assistants, for instance.

Other factors that can lead to unusual or too much strain on the plantar fascia include

• foot deformities like a pronated foot, flat foot or high arches;
• short calf muscles or a short Achilles tendon: In this case, the plantar fascia is under constant tension because it’s joined to the calf muscle by the Achilles tendon;
• uncomfortable shoes such as shoes with a hard heel. Wearing running shoes that don’t have enough cushioning and running on hard surfaces are also considered risk factors; and
• being overweight – perhaps because this can place additional strain on the plantar fascia.

Inflammatory diseases like gout, arthritis or ankylosing spondylitis are considered risk factors too because they affect the tissue.

The risk of developing plantar fasciitis also increases with age because tissue becomes less elastic and the fat pads under the heel start to get thinner.

Up to 10 out of 100 people develop plantar fasciitis at some point in their life. In adults, it's one of the most common causes of foot and heel pain. It is particularly common in 45- to 65-year-olds.

Runners develop plantar fasciitis more often and at a younger age than other people do.

In most cases, the symptoms disappear after a few months. Even when no special treatment is given, plantar fasciitis often goes away within a year.

But an estimated 10 to 20 out of 100 people who have plantar fasciitis are affected for longer than a year.

Talking to a doctor and having your foot examined is usually enough to find out whether you have plantar fasciitis. It is important that you describe your symptoms in as much detail as possible. The doctor will examine you by checking your flexed foot for tenderness in the sole or heel. They will also examine your overall foot, and look to see how you walk and whether you have a short Achilles tendon or short calf muscles.

Ultrasound scans aren't always needed for diagnosis but they are sometimes carried out before giving injections for treatment. This is done to see the inflamed area and determine where the needle should be inserted.

Other examinations such as x-rays or magnetic resonance imaging (MRI) are only needed in some cases – to rule out bone fractures, for example, or if the symptoms don’t improve despite treatment.

Continuing to put too much strain on your painful foot can make the plantar fasciitis worse. So it’s important to rest the foot at first, but it doesn’t need to be immobilized (kept still).

To ease the pain, you can cool the sole of your foot using a cool pack, for instance. You can also take painkillers as a short-term solution.

Once your foot has recovered a little, you will usually be advised to do stretching and strengthening exercises. If you have a deformed foot, your doctor will also prescribe orthopedic insoles. People who are overweight are advised to lose weight.

If your symptoms don’t improve after a few weeks, other treatments like corticosteroid (steroid) injections or extracorporeal shock wave therapy (ESWT) can be considered. ESWT involves exposing the plantar fascia to high-pressure sound waves that are passed through the skin of the heel. Surgery is considered the last option. But injections and operations have their risks. The question of whether surgery can relieve the symptoms has not been researched enough so far.

People who have plantar fasciitis need a lot of patience because it takes quite a while for the body to get the inflammation under control.

That might sound disconcerting, particularly if you do a lot of sports, but most people don't need to take a long-term break from activities that put strain on their plantar fascia. In many types of sports, it’s possible to reduce the strain by changing technique or shortening training sessions. Stopping every now and again for a rest also gives your body an opportunity to recover.

Doctors often give people with plantar fasciitis a combination of treatments, or various different treatments are tried out one after another. As well as having patience, you have to have time because there can be quite a lot of doctor’s and physiotherapist’s appointments.

But there are also plenty of things you can try yourself to ease the symptoms of plantar fasciitis. Wearing comfortable shoes with a soft, cushioning sole, and lightly massaging the sole of your foot can offer relief. Cooling the painful area before you exercise can help too. Walking barefoot, on the other hand, is not a good idea.

When people are ill or need medical advice, they usually go to see their family doctor first. Read about how to find the right doctor, how to prepare for the appointment and what to remember.