The authors present the observation of a 36-year-old man with a relapsing intraneural ganglionic cyst in the n. peroneus comm. which was resolved by extirpation incl. the stalk communicating with the bursa of the tibiofibular joint. The existence of a connection and identical signs of fibrocytes in the articular synovial membranes and bursae of intraneural cysts suggest a uniform origi n of synovial and ganglionic cysts. Preoperative diagnosis of intraneural cysts is possible by ultrasonography (US), computed tomography (CT) and above all by magnetic resonance tomography (MRT). Aimed MRT examination can help to detect the connection between the cyst and the neighbouring joi nt. Extirpation of the cyst and its stalk can prevent a relapsing course of intraneural synovial and ganglionic cysts.

        Key words: intraneural ganglion, intraneural ganglionic cyst, diagnosis of intraneural ganglia, surgical treatment of intraneural ganglia