Arthritic foot conditions often present differently from arthritis other areas of the body. Achilles tendinitis results from stress on calf muscles and Achilles tendon. This strong tendon often gets inflamed while playing sports like basketball. The tendon gets irritated and does cause moderate pain . When treated promptly, the tendinitis is relieved. Sometimes, the Achilles tendon can rupture if it is overstretched. When the Achilles tendon ruptures, one may feel a sudden pop followed by sharp pain. Rupture of the Achilles tendon makes it impossible to walk.