Ganglion cyst

• Ganglion cyst:

  • Ganglions are sacs of synovial fluid
  • Synovial fluid is found in tendon sheaths and joints - if there is herniation of the membrane covering the sheath/joint this forms an outpouching
  • The outpouching fills up with synovial fluid forming a ganglion cyst (fluid filled sac)
• Causes:

  • Idiopathic
  • Trauma
  • Osteoarthritis
• Presentation:

  • Usually aged 20-40
  • Commonly occurs in wrist and fingers
  • A visible, palpable lump appears rapidly over days
  • Usually not painful but rarely the cyst can compress nerves causing sensory or motor symptoms
• Examination:

  • Range in size: 0.5cm-5cm, but most are less than 2cm
  • Firm, smooth, well circumscribed, fluctuating lump
  • If large enough it will transilluminate
• Diagnosis:

  • Clinical diagnosis
  • If diagnosis unclear USS or MRI
• Management:

  • No management - 40-50% resolve spontaneously but can take years
  • Needle aspiration - high rate of recurrence
  • Surgical excision - remove the cyst under local anaesthetic - lower rate of recurrence but higher rate of complications e.g. infection and scaring
• Mucoid cyst in OA is a type of ganglion cyst - usually on DIP joint