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February 25, 1905


JAMA. 1905;XLIV(8):635. doi:10.1001/jama.1905.02500350045017

Myatonia—as opposed to myotonia or motor spasm-is the term applied by Oppenheim to a condition of deficiency or absence of muscular tone that he has observed especially in children during the first year or two of life. It may involve the entire body or it may be confined to certain portions, the affected parts being flaccid and motionless. The tendon-reflexes are diminished or abolished, and the involved joints are unduly movable, while active motion is impaired. The muscles supplied by the cranial nerves usually escape, as does also the diaphragm. The affected muscles are flaccid, soft and thin, and the electrical reactions are diminished quantitatively. Intelligence, sensibility and the special senses do not suffer, and the functions of the sphincters are preserved. The condition appears to be of congenital origin, and it is thought to be due to an arrest in the development of the muscles. It differs from progressive