Overview | Symptoms | Treatment | Management
The symptoms associated with Hypertonicity or Episodic Falling, also known as Hyperkinesis, Falling Cavaliers, Collapsing Cavalier Syndrome, Scotty Cramp or Paroxysmal Hypertonicity Disorder are often confused with epileptic seizures. However, Hypertonicity/Episodic Falling can be distinguished by the fact that dogs remain conscious through the event.
Hypertonicity/Episodic Falling episodes appear to be triggered by stress, apprehension, excitement and variable periods of exercise. During episodes, affected dogs display increased muscle tone and an inability to relax their muscles.
Dogs with Hypertonicity/Episodic Falling may show an array of symptoms with varying degrees and frequencies. The aging process also affects dogs individually, so dogs with this disorder may have fewer, more or no change in the frequency/severity of episodes as the dog ages. After episodes, dogs with mild symptoms usually continue as if nothing has happened. The following is a list of reported symptoms of Hypertonicity/Episodic Falling:
- cramps
- spasms
- odd events or quirks
- tumbling or freezing episodes
- falls followed by failed attempts to rise
- peculiar bounding, pelvic limb gait
- limb abduction and stiffness
- bunny-hopping gait
- arching of the spine
- vocalization
- collapse
- "deer-stalking" posture, with increasing limb stiffness, falling, and legs held in extensor rigidity
- recovery within 10 mins to 2 hours; residual effects may last up to several hours
- intense face rubbing may precede an episode
- thoracic and pelvic limb extensor rigidity followed by collapse into lateral recumbency
- may observe undulating muscle movements that induce a rippling effect of the overlying skin
- freezing or walking with the head down and to one side.
- stiffness in the back legs
- an apparent lack of coordination in the rear or front limbs
- temporary loss of control in the hind legs
- rolling or somersaulting
- laying on one side with the back legs extended, limbs may twitch
- drooling
- tightening of the muscles around the mouth with an inability to open the jaws
- eyes may appear to bulge as the muscles of the face contract.
With severe cases of this disorder, symptoms are chronic and may be induced without any apparent causes. After a severe episode, some panting may occur and the dog may rest. Some puppies become frightened and take some time to calm down. Most get used to the events with age. Severe cases of Hypertonicity/Episodic Falling are characterized by:
- the front legs curling up over the head
- rear legs become rigid through the toes
- jaws are clenched
- episodes can last for hours
- multiple episodes can happen in a short space of time
- may develop hyperthermia
- respiration may be impaired
- chronic tenderness and stiffness
The following videos demonstrate some of the symptoms of Episodic Falling in Cavalier King Charles Spaniels. We gratefully acknowledge Karen and her little Bentley, and Dorothie Hellman who runs the Cavalier Episodic Falling website for producing these excellent videos.
This first video of Karen's Bentley clearly shows that Bentley is conscious throughout his episode, distinguishing this disorder from an epileptic seizure.
Please contribute to this article! If you have a dog affected by Hypertonicity/Episodic Falling/Scotty Cramps , please send us your photos, videos and feedback so we can include them in our article. Videos and photos are particularly useful for demonstrating symptoms to new owners who may have to face this disease. Send us materials by uploading them to DogHeirs or by sending them directly to us at Team@DogHeirs.com
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