The peroneal tendons are those that run on the outside of the ankle just behind the bone called the fibula. Tendons connect muscle-to-bone and allow them to exert their force across the joints that separate bones. Ligaments, on the other hand, connect bone-to-bone.
Tendonitis is perhaps not the most appropriate term. This word implies that there is inflammation in the tendon. The reality is that there is tendinosis, which means that there is enlargement and thickening with swelling of the tendon. This usually occurs in the setting of overuse, meaning a patient or athlete doing a repetitive activity which irritates or inflames the tendon over long periods of time.
The vast majority of peroneal tendinosis will heal without surgery. This is because it is an overuse injury and can heal with rest.
If there is significant pain, a CAM Walker boot for several weeks is a good idea. If there really is no tenderness with walking, an ankle brace might be the next best step. Patients should very much limit how much they are walking or on their feet until the pain abates. This usually takes several weeks. Resumption of training can then occur, but must occur very slowly and be based on pain.
For those patients who have hindfoot varus, an orthotic that tilts the ankle to the opposite side may well help to offload the tendons. It is important to talk to your doctor about changing your training. This includes using new shoes for running or also cross-training, which means alternating activities each day. Physical therapy is also very important. This, as with ankle sprains, can be done to strengthen the tendons.
There is some interest at the moment in using platelet-rich plasma (PRP) to help stimulate healing growth. Currently, there are no studies showing that this works for the peroneal tendons.
Steroids are probably best avoided as they can actually damage tendon.
Surgical treatment is indicated if the pain does not get better with rest.
Conservative treatment - that is, without surgery - should last, however, even up to a year before considering surgery.
If there is a tear, meaning a split that runs along the length of the tendons, one could consider cleaning it out and repairing the tendon. Sometimes, making the groove in the back of the bone of the fibula deeper allows the tendons more space and can help as well.
Finally, if the tendon is very bad, one may need to resect the tendon and connect both the longus and brevis together. Only the specific tendon involved should be addressed. Occasionally, both may be involved.
Patients usually recover fully. However, this can take considerable time. You must be patient to allow the tendon to heal before going back to activity. If surgery is needed, recovery can be substantial. Commonly, patients will not be allowed to put their foot down with weight for about six weeks. Physical therapy will ensue.
The outcome is commonly good. However, sometimes it is very difficult and takes time for people to get back to their activity. When a tear develops, and there is chronic thickening of the tendon, the outcomes are not as good.
If the tendinosis is not addressed, tearing of the tendon can occur. Also, weakness of the tendons can lead to an ankle sprain. In the case of surgery, infection can develop. Nerve damage can occur if the sural nerve, which runs along the side of the foot and provides sensation to the foot, is cut or stretched. Instability itself can lead to many sprains which can damage the cartilage on the inside of the ankle.
Frequently Asked Questions
What is the difference between tendonitis and tendinosis?
The truth is that “tendinosis” is the more properly used term. Tendonitis implies inflammatory cells invade the tendons. In studies where researchers have taken the tendons and looked at them under a microscope, there really are not the types of inflammatory cells once thought. There is really more of an enlargement and thickening of the tendon. This is better termed tendinosis.
*Source: American Orthopaedic Foot & Ankle Society® http://www.aofas.org