Abstract
In two subjects with paramyotonia congenita myotonic delay in muscle relaxation, recorded electromyographically and with a displacement transducer, was found to increase with repeated forceful contractions. Myotonia was elicited readily in warm temperatures, was initially aggravated by cooling, but was invariably lost as muscle fatigue developed. The EMG evidence of myotonia usually subsided before complete muscle relaxation had occurred, suggesting that a defect of the contractile mechanism was present over and above any defect at membrane level.
Full text
PDF






Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Brust M., Cosla H. W. Contractility of isolated human skeletal muscle. Arch Phys Med Rehabil. 1967 Oct;48(10):543–555. [PubMed] [Google Scholar]
- Buchthal F., Schmalbruch H. Contraction times and fibre types in intact human muscle. Acta Physiol Scand. 1970 Aug;79(4):435–452. doi: 10.1111/j.1748-1716.1970.tb04744.x. [DOI] [PubMed] [Google Scholar]
- Burke D., Skuse N. F., Lethlean A. K. Contractile properties of the abductor digiti minimi muscle in paramyotonia congenita. J Neurol Neurosurg Psychiatry. 1974 Aug;37(8):894–899. doi: 10.1136/jnnp.37.8.894. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Haynes J., Thrush D. C. Paramyotonia congenita: an electrophysiological study. Brain. 1972;95(3):553–558. doi: 10.1093/brain/95.3.553. [DOI] [PubMed] [Google Scholar]
- Joyce G. C., Rack P. M., Westbury D. R. The mechanical properties of cat soleus muscle during controlled lengthening and shortening movements. J Physiol. 1969 Oct;204(2):461–474. doi: 10.1113/jphysiol.1969.sp008924. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MERTON P. A. Voluntary strength and fatigue. J Physiol. 1954 Mar 29;123(3):553–564. doi: 10.1113/jphysiol.1954.sp005070. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Marsden C. D., Meadows J. C., Merton P. A. Isolated single motor units in human muscle and their rate of discharge during maximal voluntary effort. J Physiol. 1971;217 (Suppl):12P–13P. [PubMed] [Google Scholar]
- Preswick G., Stewart R. D., O'Hara P., Murray I. P. The value of muscle twitch and Achilles reflex recordings in thyroid disorders. Med J Aust. 1966 Mar 19;1(12):473–477. doi: 10.5694/j.1326-5377.1966.tb72518.x. [DOI] [PubMed] [Google Scholar]
- Tanji J., Kato M. Discharges of single motor units at voluntary contraction of abductor digiti minimi muscle in man. Brain Res. 1972 Oct 27;45(2):590–593. doi: 10.1016/0006-8993(72)90488-x. [DOI] [PubMed] [Google Scholar]
