. Author manuscript; available in PMC: 2012 Feb 1.

Published in final edited form as: Ann Neurol. 2011 Feb;69(2):328–340. doi: 10.1002/ana.22238

Table 3.

Comparison of selected clinical characteristics in the Chloride and Sodium Channel Myotonias

	Chloride channel myotonia (n=18)	Sodium Channel myotonia (n=11)
Eye closure myotonia
Present (% of whole group)	56	91
Warm-up phenomenon (% of those with EC myotonia)	80	60^*
Paradoxical myotonia (% of those with EC myotonia)	20	70^*
Clinically symptomatic ^** (% of whole group)	17	82
Falls^***
Present (%)	78	27
Mild (%)	33	18
Moderate (%)	22	0
Severe (%)	22	1

EC = eye closure

Some sodium channel myotonia patients had a combination of paradoxical eye closure myotonia and warm-up

^**

The patient considers the eye closure myotonia uncomfortable or interfering with daily activities e.g. driving, walking in the cold.

^***

Mild: Infrequent falls with minor or no injuries; Moderate: fairly frequent falls, occasional injuries; Severe: ‘locking’ with trauma to head or face