The True Achilles Heel (Retrocalcaneal Bursitis)
In article #47 the most common form of bursitis in runners – trochanteric – was discussed. While there are other bursal structures about the hip and knee subject to similar injury, the second most likely bursitis condition to strike runners is to be found at the back of the foot, precisely where the Achilles tendon attaches to the heel bone, or calcaneus.
The retrocalcaneal bursa is located between the very bottom one-fourth inch of the Achilles tendon and the uppermost posterior section of the calcaneus. (Looking at a map of the state of Washington, this would roughly be represented by Puget Sound – one of the few regions left in the U.S. I want to see before I go to that great-treadmill-in-the-sky!) As at the hip, this bursa can become inflamed by either direct trauma (bruise) or repetitive friction. The offending agent for the latter is generally thought to be one of two possibilities. Some experts feel that a poor-fitting shoe with a rigid heel counter generates the friction leading to this condition. (I also believe that an excessively cushioned shoe may be causative, due to the greater degree of stress on the Achilles as the heel sinks too deeply into the shoe at heel strike.) Others blame abnormal biomechanics, unrelated to footwear, that cause increased tightness and/or excessive sideways torque of the Achilles tendon.
Retrocalcaneal bursitis is sometimes difficult to differentiate from Achilles tendinitis, at least symptomatically. Both are most uncomfortable during the push-off phase of gait, are most severely painful in the morning and with walking after sitting for a period of time, and generally worsen with activity. Most practitioners make the distinction between the two simply on the basis of location of pain and tenderness. Generally, Achilles tendinitis is felt an inch or two higher than this form of bursitis.
The initial course of treatment for this problem, after the usual ice and ibuprofen/aspirin routine or course, is to change footwear, especially if the onset of the problem was coincidental with a new pair of shoes. If this fails, a small heel lift (no more than one-fourth inch) in both shoes may provide enough biomechanical adjustment to relieve the stress and/or friction over the area. If there is still no improvement, complete rest from running is probably advised, along with a professional consultation.
It is generally not a good idea to try to “run through” this injury. Prolonged irritation of the bursa can lead to growth of a bone spur (calcaneal esthesiopathy) that infiltrates the Achilles tendon and makes eventual recover very difficult. Essentially, if it progresses to this stage it means that the entire area – bursa, tendon, sheath – has become (Warning: highly technical term coming up here) “all gunked up.” Not a good thing, and one that may eventually necessitate surgery.
Retrocalcaneal bursitis is an unpredictable, painful, and stubborn running injury that, at first sign, should be respected and addressed quickly to prevent it from becoming a more serious, chronic problem.