I appreciate your detailed inquiry regarding ganglion cysts, which are fluid-filled sacs that often appear along tendons or joints, especially around the wrist. They typically form when the synovial fluid that lubricates your joints leaks out, leading to swelling. Factors contributing to their formation include repetitive stress, overuse of the joint, or previous injuries, but many times their precise origin is unknown. Ganglion cysts can indeed occur in other areas, such as the ankle or knee. Your observations about mild discomfort when moving the wrist are significant. While many ganglion cysts are asymptomatic, they can occasionally cause pain or restrict movement, particularly if they press on nerves or occupy space needed for joint function. Signs prompting medical attention include significant pain, rapid growth, changes in color or temperature of the surrounding skin, or if the cyst interferes with normal function. Diagnosis typically involves a physical examination, and imaging tests like ultrasound or MRI may be used when the diagnosis is unclear or to assess the cyst's size and position. Often, a doctor can diagnose a ganglion cyst based merely on clinical evaluation, but imaging can provide additional information if necessary. Treatment options vary. Many ganglion cysts resolve independently without intervention. For symptomatic cases, options include aspiration to drain the fluid, splinting or immobilization to reduce activity, and potentially, surgical removal if the cyst is persistent or bothersome. Surgery may be considered when symptoms are severe, recurrent after aspiration, or if there are concerns about nerve compression. Recurrence after draining is indeed common, often because the underlying problem that led to the cyst formation persists. There are no guaranteed preventive measures, but maintaining proper ergonomics while typing or doing manual work and incorporating wrist strengthening and stretching exercises can help reduce the risk. Home remedies such as warm compresses may provide symptomatic relief, and massage may aid in reducing discomfort, but aggressive methods like striking the cyst can be dangerous and are not recommended due to the risk of injury or infection. If left untreated, ganglion cysts typically do not lead to severe complications but can cause ongoing discomfort, stiffness, or chronic pain if they interfere with joint function. Urgent medical intervention should be considered if you notice sudden changes in symptoms or if function is notably impaired. Always consult with a healthcare professional for a tailored assessment and appropriate management of your family member's condition.