Ganglion cysts are the most common masses in the foot and ankle, and can often be difficult to eradicate since drainage usually results in an eventual refilling of the cyst. Surgery is often necessary for permanent removal of these compressible lumps. This article will discuss ganglion cyst treatment, especially surgical removal.
A ganglion cyst is essentially a benign, fluid-filled mass that develops near joints and tendons. While the exact cause is unknown, it is generally thought that a defect forms in the tissue surrounding a tendon or a joint that allows fluid from one of these areas to penetrate through into the surrounding tissue. This fluid becomes walled off by fibrous tissue that surrounds it, and the cyst forms. It is essentially a balloon of thick, jelly-like fluid that becomes thicker than the joint or tendon fluid from which it came. The cysts can start off small, and then quickly grow. It is also not uncommon for cysts to wax and wane in size. These cysts are generally benign, and cause few issues on their own. However, the location and/or size of these cysts can become problematic, especially in the foot and ankle.
Cysts can sometimes be located near sensitive structures, such as nerve tissue, and the simple presence of the cyst expanding against this tissue can cause pain. Additionally, if the cyst is especially large or irregularly shaped, or if it is wrapped around joints or tendons, the function of the foot can be affected. This can lead to difficulty in walking, or pain. It is because of the above reasons that foot and ankle ganglion cysts are typically treated.
Diagnosing ganglion cysts is usually done by an external exam, as they are either visible through the skin or can be felt under the skin surface. Ganglion cysts usually feel fairly distinct, and most physicians can make a confident diagnosis by feel alone. However, if the cyst has several bumps to it, feels unusual, or is deep or in an unusual location away from a joint or a tendon, the physician may prefer to get an MRI or ultrasound study to assess its size and appearance better.
The initial treatment of ganglion cysts can involve an attempt at drainage. Cysts usually can be drained, although smaller ones are sometimes difficult to accurately find through the skin. The old technique of hitting the cyst with a heavy book, like a Bible, is very traumatic, ruptures the cyst, and can create inflammation to the entire area. This treatment is not advised in modern medicine. The best technique for drainage is for needle and syringe drainage by a physician. The drainage is usually followed by an injection of a cortisone-like medication (corticosteroid) that reduces local inflammation and may scar the cyst origin to prevent regrowth. Unfortunately, this technique does not have a great chance of keeping the cyst from returning, as the cyst wall and the cyst origin remain in the body. The cyst typically regenerates its fluid shortly after drainage. Drainage and corticosteroid injection is safe and does work in some cases, especially for small cysts, and that is why it is attempted in the first place.
When the cyst returns and creates pain or functional limitation, that is the point at which surgery is considered. Surgical removal of cysts can be simple, or can be complex if the cyst is large or integrated into surrounding tissue. The surgical procedure for removing ganglion cysts involves making an incision directly over the area where the cyst lies, and careful separation of the cyst from the surrounding tissue without rupturing the cyst. Once the cyst ruptures, the fluid that remains can potentially become walled off again, and finding the exact ending margin of the cyst wall becomes more difficult once it is ‘deflated’. The cyst must be removed in its entirety, including all of the cyst wall and the original connecting tissue. If this is not done, the cyst may simply reform. The complete removal of all this tissue is not always easy, and sometimes even the slightest of remaining tissue not visible to the surgeon can allow for a return.
Removing cysts often requires identification of several different lobes, or branches of the cyst, if it is not in one smooth piece. This exploration often requires the surgeon to gently move around surrounding vital tissues, which could have cyst material wrapped around them. This can result in a complicated removal process, and can increase the risk or likelihood of the cyst returning after surgery. It also places the surrounding vital tissue, like nerves, at risk for damage during the surgery. In rare cases, the expansion of the cyst has already damaged the surrounding tissue, and there may be lasting effects even after the surgical healing has completed.
In general, healing from removal of the cyst is successful and without complication. The skin heals readily, and deep scar tissue is not typically a problem as the cysts are usually more superficially located, aside from the base that stems from the underlying tendon or joint. An exception to this is cysts located along the back or sides of the ankle, where more tissue dissection is needed to reach the cyst. Weight bearing is usually immediately allowed, except for uncommon cysts on the bottom of the foot requiring an incision under the foot, and activity can usually be resumed in several weeks.
As one can read, ganglion cysts are a common foot mass that may be somewhat difficult to be rid of permanently. On its own, a ganglion cyst is usually benign and without significant symptoms. However, treatment is needed when the cyst causes pain or a limitation in one’s activity. As a rule, one should always have a medical exam when a new mass appears on or under the skin. There are tumors that can be mistaken for cysts, and a physician can determine what the nature of the mass is. For foot and ankle masses, a foot specialist (podiatrist) is the best specialist to see first for evaluation.