Türk Nöroşirürji Dergisi 2009 , Vol 19 , Num 1
Guyon's Canal Neuropathy Secondary to Rheumatoid Synovial Cyst
Ayhan SAĞMANLIGİL1, Saffet Meral ÇINAR2, Türker KARANCI3, Leman ERKUTLU4
1,3 Taksim Eğitim ve Araştırma Hastanesi, Nöroşirürji Kliniği, İstanbul, Türkiye
2,4 Taksim Eğitim ve Araştırma Hastanesi, Nöroloji Kliniği, İstanbul, Türkiye
Ulnar neuropathy is the most common entrapment neuropathy following carpal tunnel syndrome. Most cases are localized at elbow and localization at wrist is a rare condition. Guyon's canal neuropathy secondary to synovial cyst is reported in this article. A45-year-old female patient presented with complaints of pain, numbness and weakness in the right hand. Atrophy and weakness at the hypotenar and 1st dorsal interosseous regions, sensorial loss of half of the 4th finger and the medial palmar area and volar area of the 5th finger, and claw hand detected during the neurological examination. Nerve conduction was studied with EMG where the ulnar nerve was stimulated and qualification from the abductor digiti minimi (ADM) muscle was made. Compound muscle action potential values were observed to be very low, the sensorial action potential amplitude values were observed to be low. On needle EMG, the ulnar nerve innervated muscles flexor digitorum profundus (FDP) and flexor carpi ulnaris (FCU) were normal while denervation potentials, neurogenic motor unit differentiations and a decrease pattern were observed at the 1st dorsal interosseous muscle and ADM. Electrophysiological findings showed that the ulnar nerve was affected at the wrist level. Radiological imaging of the affected area was performed. A synovial cyst was found adjacent to the ulnar nerve‘s motor and sensorial branches at Guyon's canal. Decompression provided clinical and electrophysiological improvement. Anahtar Kelimeler : Focal neuropathy, Guyon, Ulnar nerve