This is the commonest cause of a painful heel. It is caused by inflammation and microtearing of the plantar fascia, one of the ligaments that attaches to the underside of the back of the heel. It is also associated with certain foot types as well as repetitive, strenuous activity that may cause bruising and inflammation of the back of the heel.
Patients may report it starting after overuse or a change in shoe wear.
The diagnostic feature of the history is whether the pain is at its worst on getting out of bed in the morning or after having been at a desk or behind a steering wheel for a while, so-called ‘start-up pain.’ As the foot is put down on the ground there is a sudden, searing sensation on the back of the undersurface of the heel. The pain continues and as the foot stretches out a little bit with walking, some of the pain subsides.
Typically this improves slightly, only to worsen again as standing and walking increase over the course of the day. The diagnosis of plantar fasciitis is confirmed by very specific examination of the back of the heel related to the location of the pain under the heel. There is often a nerve that is simultaneously inflamed or pinched underneath the fascia. This can aggravate the pain even further.
The main treatment involves cushioning the heel with a silicone heel pad. Stretching exercises for the back of the heel are done on a regular basis, two to three times daily. The natural position of the foot during sleep rests the fascia, which then is subjected to vigorous stress again when getting up and walking in the morning. Keeping the fascia stretched at all times (but particularly at night) seems to help.
Stretching out the foot at night using an off the shelf night splint maintains the foot in a straight up position. This prevents it from dropping down during the night. If these methods of treatment fail, a cortisone injection into the back of the heel will often reduce the inflammation. More than one cortisone injection is not a good idea because it weakens the heel pad and can even aggravate the condition. If none of these treatments are sufficient, the next alternatives are shockwave therapy or surgery. In shockwave therapy a high frequency, ultrasound impulse is transmitted to the back of the heel to break up the scarring.
You may have heard of similar treatments to treat kidney stones. This is not the same as ultrasound used by physiotherapists. Alternatively, surgery may be performed through a small incision on the back of the heel to release the plantar fascia and, in some cases, release the nerve that is pinched at the same time. The treatments may be effective in relieving the chronic pain if cushioning, stretching and immobilization fail.