Achilles Tendinitis is a painful condition of the heel of the foot.  The achilles tendon is the largest tendon in the body and connects the gastrocnemius muscle of the calf to the calcaneus bone in the foot.  The tendon is usually injured during sports or from long-standing repetitive trauma such as running.  Tendinitis is an inflammation that is caused by injury or overuse.  There are two types of achilles tendinitis; insertional and non-insertional.  Insertional tendinitis occurs on the lower part of the tendon where it attaches to the bone.  Non-insertional tendinitis occurs in the middle part of the tendon.  Injury to the tendon can cause calcification of the tendon and the development of bone spurs at its insertion.  This may aggravate the problem.  Signs and symptoms of achilles tendinits include pain in and around the back of the foot and heel, thickening and swelling of the tendon and pain.  In severe cases, the tendon may actually rupture.  X-rays are useful to exclude other causes such as fractures and to look for calcifications of the tendon.  MRI scans can look for damage and rupture of the tendon.  Treatment begins with conservative modalities including rest, alteration in activities, heat, ice, physical therapy and non-steroidal anti-inflammatory medications.  Injections of a cortisone solution around the tendon may be helpful.  However, care must be taken not to inject directly into the tendon as rupture of the tendon may occur.  In severe cases, surgical treatment of the tendon, elongation of the calf muscle or transfer of a tendon may be necessary.