BASICS
- Ganglion cysts are common benign tumors that are not related to nerve tissue (as implied incorrectly by the name).
- Can be located anywhere throughout the body but usually adjacent to or within joints and tendons, with the most common locations being the wrist, foot, and ankle
- Not a true cyst as microscopic examination does not show an epithelial lining
- Most are asymptomatic except for changing size. Local nerve compression can result in pain or activity limitation.
- Synonym(s): synovial cyst; myxoid cyst; Gideon disease; Bible bump.
EPIDEMIOLOGY
- Can affect all age groups. Unusual in children
- Most common in ages 20 to 40 years and twice as common in women
- Common in dorsal wrist, radial wrist, and dorsum of the distal interphalangeal (DIP) joint (referred to as a mucous cyst)
- Mucous cysts are usually seen in older patients.
- 60-70% of hand and wrist ganglion cysts are on the dorsal wrist; 15-20% are on the volar wrist.
Prevalence
- Prevalence of wrist ganglia in patients presenting with wrist pain is as high as 19%.
- Prevalence of ganglia in patients with a palpable mass in the wrist is as high as 27%.
- Reported prevalence in ankles is 5.6%.
ETIOLOGY AND PATHOPHYSIOLOGY
Pathogenesis is unclear. Cysts are filled with mucin and communicate with the adjacent joint space, tendon and/or tendon sheath via a stalk. Several theories about their orgin include: á
- Herniation of synovial lining creates a one-way valve. Although this is supported by dye studies, the lack of a synovial (epithelial) lining in the cyst wall makes this less likely.
- Mucoid degeneration of connective tissue results in formation of hyaluronic acid, leading to cystic space formation. Studies haven't confirmed this hypothesis.
- Joint stress leads to a tear in the joint capsule or tendon sheath allowing synovial fluid to leak into surrounding tissues. Local irritation leads to production of fluid and a pseudocapsule forms (explaining the lack of an epithelial lining).
- Recurrent stress may stimulate mucin production by nearby mesenchymal cells (seen on electron microscopy) resulting in cyst formation.
Genetics
No specific genetic links have been found. á
RISK FACTORS
- Female > male
- Osteoarthritis for mucoid cysts
- Joint trauma (possible but not proven)
COMMONLY ASSOCIATED CONDITIONS
Mucous cysts are usually associated with osteoarthritis at the DIP joint. á
DIAGNOSIS
Usually made on basis of history and physical examination á
HISTORY
- Patients presents with an asymptomatic mass that has been present for months or years (most common) or when the cyst become painful, causes weakness, increases in size or interfers with activities.
- Pain is typically annoying as opposed to debilitating.
- Variable in size and location
- May increase in size and pain with activity and recede with rest
PHYSICAL EXAM
- Mass
- Rubbery
- Subcutaneous
- May transilluminate
- Fixed to the tendon sheath and only slightly mobile
- No overlying skin changes
- Palpation may cause pain due to nerve compression.
- Small ganglions may only be palpable in full wrist flexion or extension.
- Occult ganglions are not palpable but can be quite painful.
DIFFERENTIAL DIAGNOSIS
- Carpal bossing: a small, immovable mass of bone on the back of the wrist
- Giant cell tumor, lipoma, sarcoma, hamartoma, interosseous neuroma
- Epidermal inclusion cyst
- True synovial cyst
- Anomalous musculature
- Tenosynovitis
DIAGNOSTIC TESTS & INTERPRETATION
Unless diagnosis is unclear, imaging is not necessary. á
Initial Tests (lab, imaging)
- Most are apparent clinically and do not need imaging
- Plain films can exclude bony pathology but rarely alter the course of treatment.
- Other options to exclude occult ganglions:
- Ultrasound; MRI
- Arthroscopy
- US and MRI have similar rates of sensitivity and specificity. US is less expensive than MRI but more operator-dependent.
- Arthroscopy is used for both diagnostic and therapeutic purposes and can be considered when initial workup is nondiagnostic and conservative treatment is not effective.
Test Interpretation
- Gross pathologic evaluation shows that cysts are often multilobulated.
- Microscopic exam reveals a relatively acellular outer wall with several layers of randomly oriented collagen fibers and mesenchymal cells in the collagen fibers.
- Cyst fluid is highly viscous and contains glucosamine, albumin, globulin, and hyaluronic acid.
- Histopathologically identical regardless of anatomic location
TREATMENT
Four primary treatment options include the following: á
- Reassurance and observation: Ganglia are not likely to be malignant or to cause damage. May treat with splinting and NSAIDs if desired for comfort.
- Multiple studies suggest spontaneous cyst resolution in half of patients over 5 years (1,2)[A].
- Closed rupture: historically done by hitting cyst with a book ("King James Bible treatment"Ł)
- Results in initial treatment decreased clinical symptoms by 22-66%, recurrence is common.
- Typically a home remedy.
- Aspiration: can be done in the office under local anesthesia with a 16-gauge needle at base of the cyst. Studies demonstrate mixed results on aspirations with 30-85% success with multiple aspirations (1,2)[A]. Volar wrist ganglia should not be aspirated without US guidance due to risk of damage to neurovascular structures. Mucous cysts can be aspirated, but recurrence is >50% and pain may not resolve if due to underlying osteoarthritis.
- Concurrent injection of steroids or hyaluronidase have mixed results and are not clearly more effective than aspiration alone. Steroids have the additional risk of fat atrophy and skin depigmentation.
- Multiple cyst punctures are not more effective than simple aspiration.
- Sclerotherapy or injections that increase inflammation and cause fibrosis to reduce recurrence are less common due to concerns for joint damage.
- Surgical excision
MEDICATION
First Line
- NSAIDs for pain relief
- No other medications have been shown to be effective.
SURGERY/OTHER PROCEDURES
- Recurrence rates vary among studies but have been as low as 0-28%. Results better at high-volume centers and actual recurrence rates are likely higher.
- Arthroscopic excision is as good as open excision with better cosmetic outcomes and a faster return to normal function (3)[A].
- A 6-year study comparing blind aspiration, surgery, and watchful waiting showed:
- Recurrence rates of 58% after aspiration, 39% after surgery, and 58% in untreated patients.
- Patient satisfaction was 81% with aspiration, 83% with surgery, and 53% with reassurance.
- There was no significant difference in pain, weakness, or stiffness between groups.
- Pain was reduced significantly in all groups.
- Time away from work is greater with excision compared to aspiration and reassurance.
- Neither aspiration nor surgical excision provides a clear long-term benefit over simple observation. The primary benefit of surgery is early cosmetic resolution (4)[B].
- Bottom line
- Surgery appears to provide the lowest rates of cyst recurrence but does not provide significantly higher pain reduction or patient satisfaction.
- Determine the patient's reasons for seeking medical attention. Education alone can provide adequate treatment.
ONGOING CARE
May require supervised hand therapy after surgical repair to improve stiffness and function á
FOLLOW-UP RECOMMENDATIONS
- Hand/occupational therapy may be helpful if ganglion symptoms persist despite rest.
- Manage expectations about recurrence.
PROGNOSIS
- Generally very good
- Up to 50% will resolve with watchful waiting.
- Higher rate of resolution in children
COMPLICATIONS
- Risk of recurrence is present regardless of treatment; no specific recommendations to minimize this risk.
- Risks of surgical excision include the following:
- Residual pain
- Poor cosmesis
- Neuropathy
- Stiffness and instability of the wrist, especially scapholunate ligament instability
- Open excision if arthroscopic treatment fails to resolve symptoms
REFERENCES
11 Suen áM, Fung áB, Lung áCP. Treatment of ganglion cysts. ISRN Orthop. 2013;2013:940615.22 Meena áS, Gupta áA. Dorsal wrist ganglion: current review of literature. J Clin Orthop Trauma. 2014;5(2):59-64.33 Bontempo áNA, Weiss áAP. Arthroscopic excision of gangion cysts. Hand Clin. 2014;30(1):71-75.44 Dias áJJ, Dhukaram áV, Kumar áP. The natural history of untreated dorsal wrist ganglia and patient reported outcome 6 years after intervention. J Hand Surg Eur Vol. 2007;32(5):502-508.
ADDITIONAL READING
Gant áJ, Ruff áM, Janz áBA. Wrist ganglions. J Hand Surg Am. 2011;36(3):510-512. á
SEE ALSO
Algorithm: Pain in Upper Extremity á
CODES
ICD10
- M67.40 Ganglion, unspecified site
- M67.48 Ganglion, other site
- M67.439 Ganglion, unspecified wrist
- M67.479 Ganglion, unspecified ankle and foot
- M67.469 Ganglion, unspecified knee
- M67.472 Ganglion, left ankle and foot
- M67.431 Ganglion, right wrist
- M67.412 Ganglion, left shoulder
- M67.451 Ganglion, right hip
- M67.432 Ganglion, left wrist
- M67.449 Ganglion, unspecified hand
- M67.421 Ganglion, right elbow
- M67.461 Ganglion, right knee
- M67.471 Ganglion, right ankle and foot
- M67.419 Ganglion, unspecified shoulder
- M67.422 Ganglion, left elbow
- M67.429 Ganglion, unspecified elbow
- M67.442 Ganglion, left hand
- M67.459 Ganglion, unspecified hip
- M67.411 Ganglion, right shoulder
- M67.441 Ganglion, right hand
- M67.462 Ganglion, left knee
- M67.49 Ganglion, multiple sites
ICD9
- 727.43 Ganglion, unspecified
- 727.41 Ganglion of joint
- 727.42 Ganglion of tendon sheath
- 727.49 Other ganglion and cyst of synovium, tendon, and bursa
SNOMED
- 445008009 ganglion cyst (disorder)
- 78435003 Ganglion of joint
- 19354008 Ganglion of tendon sheath
- 202936005 Ganglion and cyst of synovium, tendon and bursa
- 404098005 digital mucous cyst (disorder)
- 297194001 ganglion of foot (disorder)
- 202942009 ganglion of wrist (disorder)
- 202945006 ganglion of ankle (disorder)
CLINICAL PEARLS
- Ganglion cysts (technically not true cysts) are the most common wrist masses.
- Diagnosis is based on history and physical examination.
- Treatment options include observation, aspiration, and excision. Long-term outcomes are generally similar with all three approaches.
- Volar wrist ganglia should not be aspirated without ultrasound guidance due to the risk of damage to neurovascular structures from blind aspiration.