Atlantoaxial Instability in Small Breed Dogs: Welfare Management

Atlantoaxial instability is a malformation of the upper cervical spine causing chronic neck pain and neurological impairment in toy breeds.

Key Facts

Atlantoaxial instability (AAI) results from malformation or absence of the dens (odontoid process) at the C1-C2 junction
Chihuahuas, Yorkshire Terriers, Pomeranians and Toy Poodles are most commonly affected
Signs range from chronic neck pain and reluctance to jump, to acute tetraplegia following minor trauma or sudden movement
Surgical stabilisation provides the best welfare outcome for dogs with neurological signs; conservative management suits mild cases

Welfare Considerations

AAI causes chronic pain that owners often attribute to normal small-breed behaviour, delaying diagnosis. Affected dogs are reluctant to flex or extend the neck, cry when picked up, and avoid stairs and jumping. Sudden deterioration to tetraplegia can occur from seemingly minor incidents. Preoperative welfare management includes strict exercise restriction, harness use instead of collars and pain management. Surgical stabilisation, while technically demanding, produces durable welfare improvement in most cases.

What You Can Do

Use harnesses rather than collars on small breeds with neck pain to avoid cervical spinal loading
Seek veterinary assessment for any small breed dog showing neck pain, reluctance to move or episodic weakness
Restrict exercise strictly in medically managed dogs to prevent traumatic deterioration
Discuss surgical referral with a veterinary neurologist for dogs with neurological signs