MENISCAL CYST

MENISCAL CYST

• It is a cystic lesion which is located at peripheral margin of the meniscus and is associated with meniscal tear

• It is a condition characterized by local collection of synovial fluid in or adjacent to meniscus

• Meniscal tear causes extrusion of synovial fluid into the meniscus or adjacent to the meniscus which later concentrate  to form gel-like material

• Location – lateral or medial aspect of knee. Lateral meniscal cysts are more common than medial

• MRI – Loculated fluid hyperintense signals which has connection to adjacent meniscus and also demonstrates tera in meniscus

• Size – average 1 – 2cms (ranging from 0.1cm to 8cms)

• Clinical presentation

  • Mostly asymptomatic with popliteal mass

  • May present with pain in knee joint with joint line tenderness

  • Dr.Pisani in 1947 reported a pathognomonic sign known as “Pisani sign” – A cystic mass which was hemispherical, disappeared into knee joint on acute flexion and on extension of knee, it reappears.

• Histopathology –

  • Meniscal tissue which is composed of collagen and fibroelastic cartilage showing myxoid degeneration leading to microcyst formation with in meniscus

  •  Cyst has lining of synoviocytes which differentiates it from ganglion cyst which does not have lining

• Treatment – Excision of the cyst

Reference

• Vineet Thomas Abraham, M. Chandrasekharan and R.Nanda kumar. Ganglion cyst or meniscal cyst- a dilemma . European Orthopaedics and Traumatology, 2013. DOI 10.1007/s12570-013-0186-2

• Evan Watts. Meniscal cyst. Knee and sports- Orthobullets