Definition
A meniscus ganglion is a connective tissue cyst filled with synovial fluid or a gelatinous mass. It can develop at the base of the inner meniscus or, more frequently, the outer meniscus and usually has no connection to the joint cavity or the body surface. Since signs of wear and tear of the meniscus are often the cause of a ganglion, the meniscal ganglion occurs more frequently in patients over 50 years of age. Men are more frequently affected by the disease pattern than women.
Origin
Each knee joint has an inner (medial) and an outer (lateral) meniscus (Greek for “moon-shaped body”). The menisci consist of cartilage and are disc-shaped. They perform important tasks in the knee joint by increasing the contact surface between the joint partners (femur and tibia), compensating for unevenness (incongruities) and buffering and redistributing the pressure on the joint surface.
Due to their position in the joint, the menisci are susceptible to injuries during traumas. A torn meniscus occurs far more frequently in the inner than in the outer meniscus. In addition to traumatic injuries, the menisci can wear out over the years.
This is known as a degenerative change, the so-called meniscopathy. Initially, tiny cracks can form in the cartilage, which expand over time under constant stress. A traumatic meniscus tear as well as wear over the years can be the cause of a meniscus ganglion.
Often a meniscus ganglion is the first symptom of a previously unnoticed wear and tear of the meniscus. Each meniscal ganglion develops at the base of a meniscal tear, resulting in the accumulation of synovial fluid at the base of the meniscus. Frequently, a small cyst is formed at the edge of the meniscus at first, which extends over the edge of the damaged meniscus as it progresses.
Internal meniscus ganglion
The inner meniscus tears much more often than the outer meniscus in case of injuries. On the bottom of this tear a meniscus ganglion can develop as described. An inner meniscus ganglion is therefore often traumatic and can be caused, for example, by tears of the meniscus as in sports injuries.
