What is Plantar Fasciitis? Plantar Fasciitis is the most common foot pain diagnosis. Plantar Fasciitis is a painful inflammatory condition causing heel pain and in some cases also heel spurs. Plantar Fasciitis literally means inflammation of the plantar fascia. The plantar fascia is the connective tissue that encapsulates the muscles of the sole of the foot. It supports the foot like a bowstring between the ball of the foot and the heel. What is the Cause? Plantar Fasciitis