持続性筋線維活動によるisolated finger flexion

Isolated Finger Flexion Caused by Continuous Muscle Fiber Activity

　症例は23歳女性と86歳女性。いずれも亜急性に出現した手指の屈曲を呈した。特に第Ⅲ，Ⅳ，Ⅴ指の屈曲が目立った。それ以外の神経症状は認められなかった。抗電位依存性カリウム受容体抗体を含む血液検査にて異常は認められなかった。末梢神経伝導速度検査は正常であったが，浅指屈筋群でのみ持続的筋線維放電が得られ，1例において100〜200Hz neuromyotonia放電が認められた。これらの2症例の病像は特異であるが，これまでにisolated finger flexionとして報告されているものと類似していた。

We report two patients who presented with progres-sive involuntary flexion of fingers. Both of them were women (Case 1 and 2 were 23 year old and 86 year old, respectively) , and developed involuntary finger flexions, particularly of the ring and little fingers, fol-lowing a localized pain of their hands and forearms. The other neurological findings were not present. There was no abnormal finding in their serum, and anti-voltage-gated potassium channel antibodies were negative. Nerve conduction velocity studies revealed no obvious peripheral neuropathy or conduction block.