A myxoid cyst is a growth commonly found near the end of a finger or toe, often close to the nail. While usually harmless, its presence can sometimes lead to changes in the adjacent nail.
Understanding Myxoid Cysts
Myxoid cysts, also known as digital mucous cysts, are benign lumps that vary in size, generally ranging from 5 millimeters to 1 centimeter across. They often present with a smooth, shiny surface and can appear skin-colored, translucent, or sometimes have a reddish or bluish tint. These growths are filled with a thick, jelly-like substance rich in hyaluronic acid, a component naturally found in joints.
Myxoid cysts are a type of ganglion cyst. They often maintain a connection, or stalk, to the underlying digital joint or tendon sheath. These cysts are most frequently observed in middle-aged to older adults, particularly those between 40 and 70 years old. Women are also more commonly affected than men.
Factors Contributing to Myxoid Cyst Formation
Myxoid cysts are frequently associated with the degeneration of the adjacent finger or toe joint, often linked to osteoarthritis. In individuals with osteoarthritis, between 64% and 93% may develop myxoid cysts. This joint degeneration can lead to increased fluid production within the joint.
The excess fluid, which resembles synovial fluid, may then leak from the joint capsule. This leakage can create a bubble or sac under the skin, forming the myxoid cyst. Trauma or repetitive micro-trauma to the affected area may also contribute to cyst development. In some instances, cysts may form due to an overproduction of mucin by cells in the connective tissue, without a direct connection to joint degeneration.
Managing Myxoid Cysts
Not all myxoid cysts require intervention, especially if they are not causing discomfort or functional issues. For those seeking management, conservative approaches include observation or applying firm, consistent pressure to the cyst over several weeks, which has shown some success in reducing size. Simple drainage, or aspiration, using a sterile needle can remove the fluid, but this method often results in the cyst refilling.
More definitive treatments are available if the cyst causes pain, cosmetic concern, or interferes with daily activities. Cryotherapy involves freezing the cyst with liquid nitrogen after drainage to prevent further fluid accumulation. Steroid injections, where medication is injected into the drained cyst, aim to shrink its contents. Surgical excision, which involves removing the cyst and its connection to the joint, is considered the most effective method, with success rates often exceeding 90%. However, recurrence remains a possibility with many treatment options.