Difference between revisions of "Myotonia"

From WikiVet English
Jump to navigation Jump to search
 
(3 intermediate revisions by the same user not shown)
Line 1: Line 1:
{{review}}
 
 
{{toplink
 
|backcolour = E0EEEE
 
|linkpage = Nervous System - Pathology
 
|linktext =Nervous System
 
|maplink = Nervous System (Content Map) - Pathology
 
|pagetype =Pathology
 
}}
 
<br>
 
 
==Myotonia==
 
==Myotonia==
  
Line 45: Line 35:
 
** Herbicides  
 
** Herbicides  
 
*** For example, (2,4-D) and dicamba.
 
*** For example, (2,4-D) and dicamba.
** Hyperadrenocorticoidism  
+
** [[Hyperadrenocorticoidism ]]
 
*** This may be natural (i.e. increased endogenous steroid production), or iatrogenic (i.e. prolonged corticosteroid administration).
 
*** This may be natural (i.e. increased endogenous steroid production), or iatrogenic (i.e. prolonged corticosteroid administration).
 +
 +
 +
[[Category:Tremors and Movement Disorders]]
 +
[[Category:Muscles - Pathology]]

Latest revision as of 14:32, 9 November 2011

Myotonia

  • Myotonia is the term given to sustained muscle contraction.
  • Myotonia may be congenital or acquired.

Congenital

  • Myotonia congenita is caused by an ion channel defect.
  • Certain breeds of dogs are predisposed to myotonia congenita.
    • Chow chow
      • The condition is caused by a defect in the sodium channel.
    • Schnauzer
      • The condition is caused by a defect in the chloride channel.

Clinical Signs

  • Stiffness is present from birth.
    • Signs improve with exercise.
  • Hypertrophy of the tongue and appendicular muscles.
  • Percussion dimple formation
  • Biopsy results may:
    • Be normal, or
    • Show type 1 fibre predominance or hypertrophy.

Treatment

  • Exercise avoidance.
  • Drugs:
    • Metilxantine
    • Procainamide

Acquired

  • Acquired myotonia may be caused by:
    • Herbicides
      • For example, (2,4-D) and dicamba.
    • Hyperadrenocorticoidism
      • This may be natural (i.e. increased endogenous steroid production), or iatrogenic (i.e. prolonged corticosteroid administration).