Pterygium

A pterygium (pl.: pterygia or pterygiums) is any wing-like triangular membrane occurring in the neck, eyes, knees, elbows, ankles or digits.^[1]

The term comes from the Greek word pterygion meaning "wing".

^ Parikh SN, Crawford AH, Do TT, Roy DR (May 2004). "Popliteal pterygium syndrome: implications for orthopaedic management". Journal of Pediatric Orthopedics. Part B. 13 (3): 197–201. doi:10.1097/01202412-200405000-00010. PMID 15083121.

[pmid15083121-1] Parikh SN, Crawford AH, Do TT, Roy DR (May 2004). "Popliteal pterygium syndrome: implications for orthopaedic management". Journal of Pediatric Orthopedics. Part B. 13 (3): 197–201. doi:10.1097/01202412-200405000-00010. PMID 15083121.

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