Tony Maritato on Instagram: "What Is This Cyst on the Bottom of the Foot? 🤔 . If you’ve ever noticed a small “bubble,” bump, or lump along the bottom of your foot—especially in the arch—there’s a good chance it could be a plantar fascia cyst (often a ganglion cyst). . So… what is a cyst? . A cyst is a fluid-filled sac that forms when the body creates extra fluid inside a protective capsule. They’re non-cancerous, generally painless, and often feel like a firm, rubbery lump under the skin. . Why