Insertional Achilles tendinitis involves the lower portion of the heel, where the tendon attaches (inserts) to the heel bone. In both non insertional and insertional Achilles tendinitis, damaged tendon fibers may also calcify (harden). Bone spurs (extra bone growth) often form with insertional Achilles tendinitis. Insertional Achilles Tendinitis is pain and inflammation at the insertion of the Achilles Tendon on the heel bone. It is often associated with swelling, redness, and calcium buildup (small bump) located at the back of the heel (see picture). Pressure at the back of the heel tends to be sensitive and painful. In the clinic, some of my clients often report that certain tight shoes might cause more pain in this area from the pressure and have to sometimes resort to open back shoes.