Repeated straining in the plantar fascia, a ligament that spans from the heel to the toe, causes plantar fasciitis, according to WebMD. These strains trigger inflammation, which cause pain and swelling.
People with plantar fasciitis may notice stabbing pain near the heel when they first wake up in morning, according to Mayo Clinic. The pain can occur after sitting or standing for long periods as well. The risk of plantar fasciitis increases with age. People are more likely to develop the condition between the ages of 40 and 60. Long-distance runners and ballet dancers also tend to develop plantar fasciitis because of the stress on the heel. This condition also occurs in people who spend a lot of time walking or standing on hard surfaces.