home / pet health + safety / healthy bytes / vets for pets blog / suddenly stiff: explaining muscular hypertonicity
Default image

suddenly stiff: explaining muscular hypertonicity



For this week’s topic, I was asked by one of my co-workers to write about a condition that affects dogs called muscular hypertonicity.  Although not a common condition, it does tend to show strong breed predilection in the terrier and spaniel breeds.  Assumed to have a prominent genetic component, this is a condition that we still don’t know a great deal about, and it can vary a bit between the different breeds it seems to effect.

So, what does muscular hypertonicity look like?  It is usually preceded by exercise and excitement and results in muscle rigidity and collapse.  Dogs don’t lose consciousness and usually recover within a few minutes.  Sometimes recovery can take up to a couple of hours, and your pet may be stiff for quite a while afterwards.  Some pet parents have reported that their dogs rub their faces along the floor prior to an episode, and some observe muscle rippling in the affected limbs. 

There are no specific tests for the disease.  Bloodwork and specific muscle and nerve testing may be done to rule out other causes of the clinical signs.  Usually history, clinical signs, familial history and normal screening labwork is strongly indicative of the condition.  Fortunately, this is rarely a life threatening condition.  In rare instances, prolonged muscle contractions can lead to hyperthermia (over heating) and this can be life threatening. 

Once afflicted, this is a lifelong condition.  Some dogs have only infrequent episodes, and so their pet parents choose not to intervene.  Some dogs aren’t that lucky and so medical intervention is required.  There are a couple of medications that have shown to decrease and/or minimize clinical signs.  These medications are given daily for the life of the dog.

Muscular hypertonicity is not a common condition, but it occurs frequently enough to warrant a discussion.  If you suspect your dog is suffering from this condition, contact your veterinarian.  They may request that you video tape an episode, and they will likely run a few different tests in order to rule out other possible causes of these clinical signs.  Depending on your dog’s specific breed, there are other similar conditions that your vet may need to rule out first. 

As always, you are your pet’s best advocate!  If you think something is going on, don’t hesitate to contact your trusted veterinarian for advice.  That is what we are here for!

To more waggin’ and purrin’.  rwkj

Add a comment here
  • *indicates required field

  • read more »
Email sent Close

Thanks for leaving a comment on this page. It will now be sent to our administrator for approval and should be added to this site shortly.

our bloggers
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
  • Meet the panel
Chris AshtonCo-Founder and Co-CEO of Petplan Pet Insurance
vet tip of the week

Visit your vet at least once a year to keep your pet protected from preventable diseases.