Myxoid Cyst: Symptoms, Types, Causes and Treatment

Myxoid cysts, also called digital myxoid cysts or mucous cysts, are benign lesions most commonly found near the nails of fingers and toes. While harmless, they can be bothersome, unsightly, and sometimes painful. Understanding their symptoms, types, causes, and treatment options is essential for both patients and healthcare providers. This comprehensive guide delves into each aspect, drawing on the latest clinical evidence and research.

Symptoms of Myxoid Cyst

Myxoid cysts can be deceptively simple in their appearance but may cause discomfort and concern due to their location and potential impact on the nail. Recognizing their distinct symptoms is the first step toward diagnosis and management.

Appearance	Location	Associated Features	Source
Soft/fluctuant nodule	Near nail folds, fingers, or toes	May cause nail deformity, sometimes painful	2 3 4

Table 1: Key Symptoms

Typical Presentation

Myxoid cysts usually present as soft, dome-shaped, or fluctuant nodules. They often appear translucent and may have a gelatinous feel. Most commonly, they are located near the proximal nail fold — the base of the fingernail or toenail — but can also be found adjacent to the distal interphalangeal joint (the last joint before the fingertip) 2 3 4.

Nail Changes

A significant number of patients develop nail changes, such as:

• Grooving or indentation of the nail plate
• Nail thinning or distortion
• Occasionally, discoloration

These changes occur because the cyst can compress the nail matrix, disturbing normal nail growth 4.

Sensation and Discomfort

Although many myxoid cysts are painless, some individuals report tenderness, especially if the cyst is subjected to trauma or pressure. Cysts on the toes may be more prone to pain or relapse 4.

Other Features

• The cyst may leak a clear, viscous fluid if ruptured.
• The overlying skin may appear shiny or thin.

Types of Myxoid Cyst

While myxoid cysts are often grouped together, research highlights important distinctions based on origin, location, and underlying pathology.

Type	Location	Distinctive Feature	Source
Digital Myxoid Cyst	Near nail fold/joints	Related to joint fluid leakage	1 3 4
Juxta-articular Lesion	Close to joints (not always nails)	Myxoid stroma, less joint relation	1
Intramuscular Myxoma	Within muscle tissues	Deeper, not superficial	1

Table 2: Myxoid Cyst Types

Digital Myxoid Cysts

This is the most common type affecting the skin, particularly the fingers and toes. These cysts typically form over the distal interphalangeal joint or the proximal nail fold and are often associated with underlying joint pathology or osteoarthritis. They are sometimes referred to as "ganglia" of the joint 1 3 4.

Juxta-articular Myxoid Lesions

These are myxoid lesions adjacent to joints but not directly linked to the joint capsule or nail fold. They present similarly but may have subtle differences in cellular makeup and relationship to joint structures 1.

Intramuscular Myxoma

This is a rare, deeper variant found within the muscles rather than the skin or subcutaneous tissue. These do not present with the classic superficial cystic appearance and are less relevant in routine dermatological practice 1.

Cytopathological Differences

Although these subtypes share a gelatinous, paucicellular stroma and similar clinical features, fine-needle aspiration and histology reveal subtle differences, especially when considering cellular content and relation to joint or muscle tissue 1.

Causes of Myxoid Cyst

The development of myxoid cysts is multifactorial, involving mechanical, degenerative, and biochemical factors.

Cause	Mechanism	Key Detail	Source
Joint fluid leakage	Fluid escapes joint capsule	Common in digital cysts	3 4
Fibroblastic activity	Overproduction of hyaluronic acid	Accumulates in skin, forms cyst	2
Collagen loss	Collagen replaced by mucin	Leads to cystic space	2

Table 3: Causes of Myxoid Cyst

Joint Fluid Leakage

A majority of digital myxoid cysts result from leakage of synovial fluid from the distal interphalangeal joint into the surrounding tissue. This creates a pathway, or "stalk," connecting the joint to the cyst. This mechanism is supported by dye studies and is particularly relevant to cysts near the fingers and toes 3 4.

Fibroblastic Proliferation and Hyaluronic Acid

In some myxoid cysts, especially those not directly connected to the joint, fibroblastic proliferation in the skin increases the production of hyaluronic acid. This substance accumulates between collagen fibers, eventually replacing collagen and forming mucin-filled cystic spaces 2.

Degenerative and Age-Related Changes

Myxoid cysts are more common in middle-aged and older adults, likely due to degenerative changes in the joints and connective tissue. The loss or alteration of collagen matrix with age or repetitive trauma may predispose the skin to cyst formation 2 4.

No Evidence for Tendon Sheath or Bursal Origin

Contrary to some earlier beliefs, current studies do not support the idea that myxoid cysts originate from tendon sheaths or bursae 2.

Treatment of Myxoid Cyst

Management of myxoid cysts aims to relieve symptoms, improve appearance, and minimize recurrence. Treatment decisions depend on the cyst’s size, location, symptoms, and patient preference.

Treatment	Method	Success/Recurrence	Source
Surgical Flap	Flap repair over cyst	High cure, low recurrence (fingers)	3 4
Sclerotherapy	Polidocanol injection	~78% resolution by 12 weeks	5
Cryosurgery	Liquid nitrogen spray	Effective with double freeze	7
Steroid Injection	Triamcinolone	Simple, effective, but some recurrence	2
Excision	Surgical removal	Higher recurrence, risk of scarring	2 6

Table 4: Treatment Options

Minimally Invasive Surgical Flap

Recent studies favor a minimally invasive flap technique for digital myxoid cysts. This procedure involves:

• Raising a skin flap over the cyst and underlying tissue, identifying and sealing the leakage point from the joint.
• No removal of skin or bone is necessary.
• Results show high cure rates (94% for fingers) and low recurrence, particularly when the connection to the joint is repaired.
• This approach is less effective for toe cysts, which have higher relapse rates 3 4.

Sclerotherapy

Polidocanol sclerotherapy involves:

• Evacuating the cyst contents and injecting a sclerosing solution (polidocanol).
• Achieves complete resolution in nearly 78% of cases within 12 weeks.
• Performed in an office setting; side effects are minor and transient 5.

Cryosurgery

Cryotherapy with liquid nitrogen:

• Uses a spray technique with a double freeze-thaw cycle for best results.
• Effective for digital cysts, though recurrence may be higher with a single freeze 7.

Steroid Injection

Triamcinolone injection directly into the cyst:

• Reduces inflammation and mucin production.
• Simple, office-based, and often effective, but recurrence is not uncommon 2.

Excision and Other Destructive Methods

• Surgical excision or removal of the cyst and surrounding tissue was once common but is now less favored due to higher recurrence rates and risk of permanent scarring or nail dystrophy 2 6.
• Removal of the overlying skin or osteophytes (bone spurs) is not usually necessary and does not improve outcomes 3 6.

Other Considerations

• Nail fold involvement: In some cases, en bloc excision of the nail folds may be performed, but this is reserved for specific indications 6.
• Recurrence: Relapse is more likely with toe cysts than finger cysts, regardless of the method used 3 4.
• Nail changes: Most nail deformities resolve once the cyst is treated successfully 4.

Conclusion

Myxoid cysts are common, benign lesions that can impact comfort and appearance, especially near the nails. Understanding their symptoms, types, causes, and treatment options allows for better patient care and informed decision-making.

Key Points:

• Myxoid cysts usually appear as soft, fluctuant nodules near the nail folds, most often in adults 2 3 4.
• There are several types, with digital myxoid cysts being most common; others include juxta-articular lesions and intramuscular myxomas 1.
• Causes include joint fluid leakage, fibroblastic proliferation, and age-related changes; they do not arise from tendon sheaths or bursae 2 3 4.
• Treatments range from minimally invasive flap surgery (with high cure rates for finger cysts), sclerotherapy, cryosurgery, to steroid injection; excision is less favored due to recurrence and scarring risks 2 3 4 5 6 7.
• Toe cysts have a higher recurrence risk than finger cysts, and most nail changes resolve after successful treatment 3 4.

By recognizing these aspects, patients and clinicians can work together to choose the most appropriate, effective, and least invasive management strategy for myxoid cysts.