CASE                               23                               

A 28-year-old woman presents to your office with complaints of pain with full wrist extension, particularly when she is practicing yoga. She does not report any antecedent trauma. Initial inspection of the wrist at neutral does not reveal any abnormality. The patient is tender over the scapholunate interval. With full flexion, a slight fullness is appreciable at the scapholunate interval. A Watson scaphoid shift test is negative. X-rays are unremarkable.

What is the most likely diagnosis?

1. Kienbock disease (idiopathic avascular necrosis of the lunate)

2. Scapholunate ligament injury

3. Sprain of the extensor carpi radialis longus tendon

4. Occult dorsal wrist ganglion

5. Extensor tenosynovitis

Discussion

The correct answer is (D). Kienbock disease would present with pain over the lunate, not the scapholunate interval. A scapholunate ligament injury would should DISI deformity on x-ray and have a positive Watson scaphoid shift test. A sprain of the ECRL would have pain with resisted wrist extension and would be unlikely to have significant swelling of the dorsal wrist, nor would there be pain over the scapholunate interval. Extensor tenosynovitis would present with a dorsal wrist swelling that moves with tendon excursion.

The patient refuses MRI evaluation and is lost to follow up. She represents 6 months later with a large mass on the dorsal wrist.

What additional information is not consistent with a presentation of ganglion cyst of the dorsal wrist?

1. A history of the mass increasing and decreasing in size

2. A mobile, firm mass on physical examination

3. Aspiration of clear, thick fluid

4. A mass that does not trans-illuminate with pen light

5. Pain of the dorsal wrist

Discussion

The correct answer is (D). A ganglion cyst will transilluminate. A mass that does not transilluminate is concerning for a solid mass and requires further workup. Ganglion cysts can often change in size secondary to the mass decompressing into the joint and refilling with fluid. The ganglion cyst is expected to be firm and mobile. Aspiration of thick, mucinous fluid is pathognomonic for ganglion cyst. Pain can be associated with ganglion cysts, particularly if it is causing pressure on an adjacent nerve.

Which of the following treatment options has the lowest risk of recurrence?

1. Rupture

2. Injection

3. Aspiration

4. Incision

5. Excision

Discussion

The correct answer is (E). Rupture, aspiration, and incision do not remove the cyst

wall or the stalk connecting the cyst to joint fluid. Therefore, excision is the treatment with the lowest recurrence rate.

The patient undergoes dorsal ganglion excision through a transverse approach. She returns to yoga without incident. However, 5 years later she represents with a volar wrist mass.

Which of the following is true regarding volar wrist ganglion cysts?

1. Aspiration to confirm diagnosis is contraindicated

2. The cyst is most likely to arise from the first metacarpotrapezial joint

3. The cyst is confluent with a flexor tendon sheath

4. Volar wrist ganglion cysts rarely cause pain

5. Volar wrist ganglion cysts are not associated with nerve palsy

Discussion

The correct answer is (A). Aspiration of volar ganglia is generally deferred to avoid inadvertent puncture of the radial artery, which often overlies or travels through the cyst on the radial side, or to avoid the ulnar artery and nerve on the ulnar side. The volar cyst is more likely to arise from the radiocarpal joint, followed by the scaphotrapezial joint followed by the metacarpotrapezial joint. The flexor tendon sheath can form a ganglion cyst, or retinacular cyst, but it is not confluent with a volar wrist ganglion. Both volar wrist ganglion and dorsal wrist ganglion cysts are associated with pain. Volar wrist ganglion cysts can cause a compressive neuropathy and associated palsy, particularly of the ulnar nerve within Guyon’s canal.

The patient is so pleased with her care that she returns with her 72-year-old grandmother who notes a mass overlying her index distal interphalyngeal joint and nail grooving. The diagnosis is made of mucous cyst.

Which of the following is true regarding mucous cyst management?

1. The nail grooving is completely irreversible

2. Mucous cysts excision is performed without disturbing the underlying bone

3. A ruptured cyst puts the patient at risk of paronychial infection

4. A excision of a large, attenuated cyst often requires a rotational flap for coverage

5. Mucous cysts are often seen overlying normal joints without arthritic changes

Discussion

The correct answer is (D). Nail grooving may be reversible with resolution of the cyst by relieving pressure on the sterile matrix. Excision of the underlying osteophyte is recommended to prevent cyst recurrence. A ruptured cyst puts the patient at risk for septic arthritis. Excision of a large, attenuated cyst often requires excision of overlying poorly perfused skin, and coverage of the underlying joint is achieved with a rotational flap. Mucous cysts are associated with arthritic joints.

Objectives: Did you learn...?

Recognize the presentation of occult and frank dorsal wrist ganglia? Describe the treatment of ganglion cysts with the lowest risk of rupture?

Understand the difference in management between dorsal and volar wrist ganglia? Understand the presentation and management of mucous cysts?