Achilles Tendonitis is the inflammation of the achilles tendon, which is the large tendon that attches to the heel on the back of the leg. Achilles tendonitis should not be left untreated due to the danger that the tendon can become weak and rupture.Cause:There are several factors that can cause achilles tendonitis. The most common cause is over-pronation. When the arch collapses it adds stress on the achilles tendon. Additionally, improper shoe selection, inadequate stretching prior to athletic activities, a short achilles tendon, congenital or due to overdevelopment without proper stretching, or injury to the tendon can also cause to achilles tendonitis.Treatment and Prevention:A stretching program should be used by all athletes, especially runners, to properly warm-up the muscles. Ice can be applied after activities, and a reduction in the length of the activity may help. An orthotic device will provide extra support, control pronation and reduce stress on the achilles tendon. If the problem persists, consult your orthopedic specialist.