Ganglion Cyst

Patients describe a visible lump that fluctuates in size with activity and may be painful at the extremes of joint movement. Pain is usually mild and intermittent; cosmetic appearance and concern about malignancy are common drivers of presentation. Volar wrist ganglions may compress the median nerve in the carpal tunnel or produce vascular symptoms by compressing the radial artery.

Examination:

• •A firm, smooth, fluctuant, well-circumscribed swelling at one of the typical sites
• •Transillumination is classically positive (a torch held against the cyst illuminates it); solid lumps do not transilluminate
• •Mobile but tethered to the underlying joint or tendon sheath; does NOT move freely with the skin
• •Tinel's sign over a volar ganglion can elicit referred symptoms if compressing the median nerve

Dorsal wrist ganglion: between the second and fourth dorsal compartments, between the scapholunate region and the extensor tendons. Volar wrist ganglion: close to the radial artery - Allen's test before any intervention is essential to confirm patency of the ulnar arch. Flexor tendon sheath ganglion: firm pea-sized lump at A1 pulley, fixed to the sheath and does NOT move with tendon excursion. Mucous cyst: at the DIP joint with overlying skin thinning and possible nail-plate grooving.

Differentials include lipoma (softer, mobile with skin), giant cell tumour of the tendon sheath (firmer, non-transilluminating, often pigmented), epidermoid inclusion cyst, dorsal carpal boss (bony, immobile), and rare malignant soft tissue tumour.

Ganglion cyst is a clinical diagnosis in typical presentations and no imaging is required.

Ultrasound is useful when:

• •Diagnostic uncertainty (atypical site, non-transilluminating, recent rapid change)
• •Differentiating from solid lesions (giant cell tumour, lipoma, neuroma)
• •Identifying an occult dorsal ganglion in unexplained wrist pain
• •Guiding aspiration or injection

Ultrasound shows a well-defined anechoic lesion, often with a visible stalk connecting to the joint or tendon sheath. Doppler distinguishes from vascular pathology.

MRI is reserved for:

• •Persistent suspicion of occult ganglion when ultrasound is equivocal
• •Pre-operative planning in volar wrist ganglion (proximity to the radial artery)
• •Excluding alternative pathology when atypical features are present

Plain radiographs are indicated when there is mucous cyst presentation (assessing underlying DIP osteoarthritis), suspected bony pathology, or volar lesions where carpal anatomy may be relevant.

Most ganglion cysts are managed conservatively. NICE CKS / BSSH support reassurance and watchful waiting as first-line for asymptomatic disease, given the high spontaneous resolution rate (~50% at 6-12 months).

First-line: reassurance, education, and reassessment at intervals. Discuss the high rate of spontaneous resolution and the benign nature of the lesion. Activity modification where a specific provocative task is identified.

Second-line: aspiration with or without corticosteroid injection.

• •Performed under local anaesthetic with a large-bore needle (16-18G); ultrasound guidance improves accuracy for small or volar cysts
• •Cure rate ~30-50% at 6 months; recurrence is common, particularly for dorsal wrist ganglions and after a single aspiration
• •Volar wrist ganglion: Allen's test first to confirm patency of the ulnar arch. Ultrasound guidance is preferred given proximity to the radial artery
• •Avoid aspiration of mucous cysts where the cyst overlies an osteoarthritic DIP joint and skin is thin - high infection risk and poor recurrence outcomes

Third-line: surgical excision.

• •Indicated for persistent symptoms, large size, vascular or neurological compression, or recurrence after aspiration
• •Open excision is the UK standard; arthroscopic excision of dorsal wrist ganglions is an emerging option in specialist centres
• •Day-case under regional anaesthetic. Recurrence rate ~5-15% after open excision, lower than after aspiration
• •Mucous cysts require excision of the cyst plus debridement of the underlying DIP osteophyte to reduce recurrence

Referral pathway: refer for hand surgery opinion when there is persistent functional impairment, recurrence after aspiration, vascular or neurological compression, diagnostic uncertainty, or atypical features. Routine asymptomatic ganglions can be managed in primary care.

Conservative pathway: no specific rehabilitation is required. Where the cyst is symptomatic, hand-therapy-led range-of-motion exercises and activity modification advice can help reduce discomfort.

Post-aspiration: keep the puncture site dry for 24 hours; resume normal activity from day 2. No formal rehabilitation. Recurrence may occur over weeks to months and is not a sign of treatment failure.

Post-operative (open excision):

• •Day 0-3: bulky dressing, elevation, oedema management. Early active range-of-motion exercises encouraged
• •Day 3-14: dressing change at clinic; sutures removed at 10-14 days. Scar massage commences
• •Week 2-6: progressive return to normal activity; office work within 1-2 weeks, manual work within 4-6 weeks
• •Week 6-12: full sport and unrestricted use

Mucous cyst excision: full nail-plate growth is required to assess for resolution of any associated nail dystrophy and takes 6-9 months.

Persistent stiffness, ongoing pain, or wound issues beyond 3 months warrant hand-therapy reassessment. Counsel patients pre-operatively about the small (~5-15%) recurrence rate even after surgical excision.

• •NICE CKS Ganglion - Supports reassurance and watchful waiting as first-line for asymptomatic disease; refer for symptomatic, recurrent, or atypical lesions.
• •BSSH Ganglion Patient Information - UK hand-surgery framework: open excision remains the surgical standard with recurrence rate ~5-15%, lower than aspiration.
• •Dias & Buch (2003) - Long-term follow-up showed approximately 50% spontaneous resolution of dorsal wrist ganglions at 6 years; supports observation as a reasonable first-line strategy.
• •Kang et al. (2008) - Aspiration alone produced ~30-40% cure rate at 6 months for dorsal wrist ganglions; combination with steroid did not significantly improve outcomes.
• •Arthroscopic vs open excision meta-analyses (Kang 2013, Yang 2020) - Arthroscopic excision shows comparable recurrence rates to open with reduced post-operative stiffness in selected dorsal wrist ganglions, though open remains standard practice.

• •Transillumination supports a ganglion diagnosis at no cost - solid lesions do not transilluminate. Atypical features (hard, fixed, non-transilluminating, rapid growth) need imaging and referral.
• •Dorsal wrist ganglion (60-70%) arises from the scapholunate ligament. Volar wrist ganglion arises from the radioscaphoid or scaphotrapezial joint and sits close to the radial artery; Allen's test before any intervention.
• •An occult dorsal ganglion is a cause of unexplained dorsal wrist pain in a young adult. MRI or ultrasound confirms the diagnosis when examination is otherwise normal.
• •Spontaneous resolution occurs in approximately 50% within 6-12 months. Reassurance and watchful waiting are first-line for asymptomatic disease.
• •Mucous cysts are associated with DIP osteoarthritis and can produce nail-plate grooving. Excision must include debridement of the underlying osteophyte to reduce recurrence.
• •Aspiration cure rate is ~30-50%, with high recurrence. Open surgical excision has the lowest recurrence (~5-15%) and is the UK gold standard for symptomatic, persistent, or recurrent disease.