Myotonia congenita is a hereditary muscle disease that belongs to a group of myotonic disorders seen in children. Myotonia congenita comes in two forms; autosomal dominant form (DMC), also known as Thomsen’s disease, and autosomal recessive form, or recessive generalized myotonia (RGM). The autosomal dominant myotonia congenita is slightly less severe, although both forms are non-dystrophic and non-progressive disorders with the main characteristic of myotonic stiffness. This stiffness occurs when after a period of rest sudden movement is performed. The myotonia congenitas result from a gene defect in Chromosome 7 that results in a chloride channel mutation affecting the skeletal muscle tissue.
A rare inherited disorder in which muscles do not readily relax after use but remain bulging and stiff, especially when the person is tired and has been inactive; a mild, non-progressive muscular disorder. A related disorder brought on by exposure to cold is paramyotonia congenita.
A benign disease characterized by tonic spasms of the muscles induced by voluntary movements. The condition is usually congenital and is transmitted by either dominant or recessive genes.
A rare inherited disease that often runs in families and has an unknown origin. It begins in early childhood and is marked by a noticeable delay in muscle relaxation after intentional movement. Exposure to cold, heat, exhaustion, and hunger can exacerbate the symptoms. While it doesn’t reduce life expectancy, its effects are more pronounced from infancy to adolescence, then tend to diminish with age. There’s no known case of it resolving on its own. This condition is also referred to as Thomsen’s disease.