Overview
What are ganglion cysts?
A ganglion cyst is a benign lump that forms when synovial fluid leaks from a joint capsule or tendon sheath and accumulates in the surrounding tissue. This results in a smooth, round, or oval swelling that can vary in size and sometimes change with movement or rest.
Ganglion cysts are most frequently found in the wrist or hand but can also occur in the foot, ankle, or other joints. They are not cancerous, do not spread, and often resolve on their own. However, if the cyst presses on nearby nerves, it can cause pain, weakness, or tingling.
These cysts are most common in women between 20 and 40 years of age but may appear in anyone, including children and older adults.
Common areas where ganglion cysts develop
Ganglion cysts can form around any joint or tendon, but they are particularly common in the following areas:
- Back of the wrist: The most frequent location, often noticeable as a firm lump that may fluctuate in size.
- Palm side of the wrist: Can cause discomfort when bending or putting weight on the wrist.
- Base of the fingers: Appears as a small bump near the finger joint, sometimes tender to touch.
- Top or underside of the foot: May develop due to irritation from footwear or repetitive movement.
- Ankle area: Occasionally forms after an injury or repeated strain.
Understanding where these cysts typically occur helps guide both diagnosis and treatment, especially for patients experiencing localised pain or swelling.
Symptoms and Causes
Recognising the symptoms
Ganglion cysts can vary in size and severity. Some are small and hardly noticeable, while others form prominent lumps that interfere with movement. Common symptoms include:
- A smooth, round or oval lump located near a joint or tendon.
- Changes in size over time, sometimes getting larger with activity and smaller with rest.
- Discomfort or aching, especially when using the affected joint.
- Tingling, numbness, or muscle weakness if the cyst compresses a nerve.
- Restricted range of motion in the affected joint.
Some cysts appear suddenly, while others develop gradually. In some cases, they shrink or disappear without any treatment.
What causes ganglion cysts?
The exact cause is not fully understood, but certain factors are known to contribute:
- Joint or tendon irritation: Repeated use or minor injury may weaken the joint capsule or tendon sheath, causing fluid leakage.
- Wear and tear: Degenerative changes in the joint tissues can lead to cyst formation.
- Repetitive strain: Frequent wrist or hand movement increases risk, especially in sports or manual work.
- Arthritic joints: Particularly in the fingers, arthritis can trigger ganglion cysts.
- Age and gender: Most common in women aged 20–40, though they can occur at any age.
Diagnosis and Tests
Diagnosis is usually made through a physical examination, as most cysts have a typical appearance and texture. If the diagnosis is uncertain or symptoms are severe, additional tests may be performed.
Common diagnostic methods include:
- Physical examination: The doctor inspects and palpates the lump to assess size, texture, and movement.
- Transillumination test: A light is shone through the cyst to confirm it is fluid-filled.
- Ultrasound scan: Helps differentiate between a cyst and a solid lump and shows its connection to nearby structures.
- MRI scan: Used for deeper or complex cysts to check involvement of tendons or nerves.
- X-ray: May be ordered to rule out bone abnormalities or arthritis.
Proper diagnosis ensures that other conditions, such as lipomas or bone cysts, are excluded.
Management and Treatment
Ganglion cysts are benign and often resolve without treatment. However, if they cause discomfort, restrict movement, or are cosmetically concerning, treatment may be recommended.
- Observation: If the cyst is painless, monitoring over time may be all that is required, as many disappear naturally.
- Immobilisation: Wearing a wrist brace or splint can reduce movement, helping relieve pain and possibly shrink the cyst.
- Aspiration: A simple, minimally invasive procedure that involves draining the fluid using a needle. While quick, cysts can recur because the cyst wall remains.
- Surgical removal: Recommended for persistent or recurrent cysts. The cyst and its stalk are completely excised to prevent regrowth. Surgery is typically successful, though a small chance of recurrence remains.
- Post-treatment care: Rehabilitation exercises may be advised to restore strength and flexibility.
Avoid attempting to burst or press the cyst yourself, as this can cause tissue damage or infection.
Outlook/Prognosis
Ganglion cysts are harmless and do not turn into cancer. Many resolve spontaneously without any treatment. Even when medical intervention is required, the prognosis is excellent.
Recurrence can occur, particularly after aspiration, but surgical removal greatly reduces this risk. Most people regain full, pain-free joint function and experience no long-term complications after appropriate management.
Prevention
Can ganglion cysts be prevented?
While there is no guaranteed way to prevent ganglion cysts, maintaining healthy joints and minimising repetitive strain can help reduce the likelihood of developing them.
Preventive steps include:
- Limiting repetitive wrist or hand movements when possible.
- Using ergonomic tools and wrist supports during daily activities.
- Strengthening the muscles and tendons that support frequently used joints.
- Treating joint or tendon injuries promptly to prevent fluid leakage.
- Incorporating regular stretching and rest breaks into work routines.
Even with preventive care, ganglion cysts can still develop, particularly in individuals who frequently use their hands or wrists for repetitive tasks.
