A ganglion cyst is a cystic mass located near a joint, with an unclear etiology. Chronic injury resulting in an increase of synovial fluid within the synovial cavity, leading to cystic herniation, or mucinous degeneration of connective tissue may represent key factors in its development. Clinically, synovial cysts occurring at the smaller joints of the hands and feet (e.g., the dorsal radiocarpal joint or the midtarsal joint of the foot) and ganglion cysts originating from tendon sheaths are collectively referred to as ganglion cysts. Cystic herniations involving larger joints are classified separately, such as those in the posterior knee region, which are termed popliteal cysts or Baker's cysts.
Clinical Manifestations
This condition is more commonly observed in women and adolescents. The highest incidence occurs at the dorsal wrist, the radial flexor carpi tendon, and the dorsal foot. Cysts are also frequently found at the metacarpophalangeal joints and proximal interphalangeal joints of the fingers.
A slowly enlarging mass often develops at the site of the lesion. Small cysts are typically asymptomatic, but larger cysts may create a sensation of soreness or distension during joint movement once they reach a certain size. On examination, a 0.5–2.5 cm round or oval mass can be identified. The surface is smooth and non-adherent to the skin. Due to the fluid-filled nature of the cyst, high internal tension often gives it the sensation of firm rubber-like consistency when palpated. Cysts with a narrow neck tend to exhibit slight mobility, while those with a larger neck are less mobile and can sometimes be mistaken for osseous lesions. Applying significant pressure to the cyst may induce soreness or discomfort. Aspiration with a coarse needle may yield a translucent, jelly-like substance.
Treatment
Ganglion cysts may occasionally rupture spontaneously through external pressure, resolving without intervention. Various treatment approaches are available clinically, though a high rate of recurrence is observed.
Non-Surgical Treatment
After evacuating the cyst contents, interventions such as injecting medications into the cyst cavity or inserting removable sterile foreign bodies (e.g., thick suture material) may be implemented to promote adhesion and obliteration of the cavity. A commonly applied method involves injecting 0.5 ml of prednisolone acetate into the cyst followed by compression dressing. This technique is simple, minimally painful, but presents a certain rate of recurrence.
Surgical Treatment
Ganglion cysts of the finger tendon sheath are generally small and associated with a high recurrence rate following aspiration. Patients experiencing multiple recurrences may require surgical excision. Complete removal of the cyst, including its wall, is necessary during surgery to reduce the likelihood of recurrence. For cysts originating from the tendon sheath, excision of a portion of the adjacent sheath should be considered. If the cyst arises from synovial herniation of the joint capsule, the base of the hernia should be ligated and excised, and the joint capsule should be repaired to minimize recurrence risk.