A ganglion is a sac-like swelling or cyst formed from the tissue that lines a joint or tendon. The tissue, called synovium, normally functions to produce lubricating fluid for these areas. A ganglion is a cyst formed by the synovium that is filled with a thick jelly-like fluid. While ganglia can follow local trauma to the tendon or joint, they usually form for unknown reasons. Occasionally, ganglia are early signs of arthritis that will become more obvious in the future
It is a biological tissue mass, most commonly a mass of nerve cell bodies. Cells found in a ganglion are called ganglion cells, though this term is also sometimes used to refer specifically to retinal ganglion cells. A ganglion cyst is a small lump most commonly on the hand or foot, not believed to be of nerve cells.
Ganglions are common and can occur at any age to both sexes.
In neurological contexts, ganglia are composed mainly of somata and dendritic structures which are bundled or connected together. Ganglia often interconnect with other ganglia to form a complex system of ganglia known as a plexus. Ganglia provide relay points and intermediary connections between different neurological structures in the body, such as the peripheral and central nervous systems.
There are two major groups of ganglia:
*Dorsal root ganglia (also known as the spinal ganglia) contain the cell bodies of sensory (afferent) nerves……
*Autonomic ganglia contain the cell bodies of autonomic nerves.
In the autonomic nervous system, fibers from the central nervous system to the ganglia are known as preganglionic fibers, while those from the ganglia to the effector organ are called postganglionic fibers.
The term “ganglion” usually refers to the peripheral nervous system.
However, in the brain (part of the central nervous system), the “basal ganglia” is a group of nuclei interconnected with the cerebral cortex, thalamus and brainstem, associated with a variety of functions: motor control, cognition, emotions, and learning.
Ganglions range in size from that of a small pea to that of a plum. They’re usually found on the back of the wrist, but also appear at its front, or on the palm or fingers.
They’re harmless and in general don’t cause any problems, but when large they’re more likely to get knocked, and if visible they can cause embarrassment.
Occasionally, a ganglion may become inflamed and feel uncomfortable, and in rare cases it may compress a nearby nerve. If this occurs, odd sensations may be felt in the hand, and finger movements may become difficult.
Ganglion cysts are idiopathic, but presumably reflect a variation in normal joint or tendon sheath function. Cysts near joints are connected to the joint and the leading theory is that a type of check valve forms that allows fluid out of the joint, but not back in. The cyst contains clear fluid similar to, but thicker than, normal synovial fluid. They are most often found around the wrist joint, especially at the scapho-lunate joint, which accounts for 80% of all ganglion cysts.
As no one really understands why ganglions occur, it’s not possible to prevent them. They don’t need treatment and many disappear of their own accord, but if a ganglion is causing discomfort or embarrassment, it can be surgically removed.
It’s important to do this if the ganglion is causing symptoms related to nerve compression.
With surgery, the recurrence rate is reduced to 5 to 10% if the check valve at the joint capsule is removed. Arthroscopy of the wrist is becoming available as an alternative to open excision of ganglion cysts.
An out-dated method of treating a ganglion cyst was supposedly to strike the lump with a large heavy book, causing the cyst to rupture and drain into the surrounding tissues. An urban legend states that since even the poorest households often possessed a Bible, this was commonly used, which led to the nicknaming of ganglion cysts as “Bible bumps” or “Gideon’s disease.”
Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.
- Questions to Ask Your Doctor About Ganglion Cysts (everydayhealth.com)
- What could hard lump on my wrist be? (zocdoc.com)
- I have a strange bump on the back left side of my wrist. What could this be? (zocdoc.com)
- What should I do about a cyst on my face near my eye? (zocdoc.com)
- Abnormal neural activity recorded from the deep brain of Parkinson’s disease and dystonia patients (eurekalert.org)
- Abnormal neural activity recorded from the deep brain of Parkinson’s disease and dystonia patients (scienceblog.com)
- New microscope decodes complex eye circuitry (eurekalert.org)
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