The Achilles tendon attaches to the heel bone (the calcaneus) over a very broad area. Although the tendon is only approximately one-centimeter thick, its attachment spreads over a three and a half-centimeter area on the calcaneus. Recurrent stress on the tendon where it attaches (the insertion) leads to inflammation, microscopic tearing of the tendon, swelling and pain. This can be associated with inflammation of the space between the tendon and the calcaneus, called the retrocalcaneal bursa.
At times the back of the heel can begin to enlarge and get quite thick. The thickening is partly as a result of bone spurs that may develop on the back of the calcaneus. These can then grow up into the substance of the Achilles tendon causing further wear and tear of the tendon.
Symptoms of insertion of the Achilles tendon include:
• Enlarged and thickened heel
A foot and ankle surgeon can diagnose an insertion of the Achilles tendon by physical exam as well as using diagnostic imaging, such as an x-ray.
Treatment of the insertion of Achilles tendonitis begins with rest, elevation of the heel on the sole of the shoe and physical therapy treatments. All of these are designed to decrease the inflammation on the tendon. Inflammation occurs with every step taken when walking because of the stretching of the Achilles tendon.
Padding of the shoe, elevated heels and physical therapy treatments are commonly successful. Cortisone (steroid injection) should not be used to treat inflammation of the insertion of the Achilles tendon since this can lead to further deterioration of the tendon itself.
If conservative treatments are not sufficient, surgery may be the best treatment option. The surgical procedures performed are varied and are determined by the underlying problem. For example, if the bone on the back of the heel is very prominent and is digging into the Achilles tendon, the bone is trimmed and shaved.
Alternatively, the tendon may need to be repaired if there is tearing of the tendon where it attaches to the bone. In addition to repairing the tendon, a transfer of a tendon may be used (transferring the tendon to the big toe, called the flexor hallucis longus). This tendon transfer adds strength and support to the weakened damaged tendon.