69 Neck pain
Presenting signs may include: low head carriage, not lowering the head to eat from the floor, shaking, trembling, neck spasms which may create a ventral head bob, episodic circling (small radius) and moving the neck and trunk as one unit.
Common causes of neck pain include intervertebral disc disease, meningitis and syringomyelia. All may present acutely. Disc disease is more likely than the others to give rise to ataxia and paresis (see Fig. 69.1). The pain may appear episodic in disc disease and syringomyelia. Meningitis may be multi-focal, and while signs may appear worse on some days compared with others, they are never entirely absent. Haemorrhage into the subarachnoid space causes spinal pain.
Focal lesions of the canine cerebrum may present as neck pain. In the absence of other signs of cerebral disease such as seizures and behaviour change, this can create a diagnostic dilemma. Consider the age and breed of dog and comb the history for clues which may suggest either cerebral disease or cervical spine or cord lesions. Consider imaging techniques which will encompass all realistic differential diagnoses. Remember that hypoventilation increases ICP which could result in herniation followed rapidly by death during anaesthesia of patients with brain tumours.
The dog was unable to rise from lateral recumbancy without assistance but when standing was ambulatory with a shortened fore and hindlimb stride length. No neurological deficits were present. Neck pain was severe.
Discospondylitis is the infection of the disc space and contiguous vertebral endplates. Bacteria gain access via the bloodstream (dental disease, endocarditis, urogenital, skin or respiratory tract infection) or by extension (migrating grass awn, direct trauma – pharyngeal stick injury). Fungal infection has been reported.
Young to middle-aged large-to-giant breed male dogs are affected most commonly. Some 18-28% of dogs have multiple areas affected, with the highest incidence in the lumbar region, especially L7–S1, followed by the thoracic and cervical spines. Extension to the vertebral canal and meninges is rare. Discospondylitis has a similar presentation in cats.
The chief presenting sign is spinal pain, with or without fever. A stiff, stilted hindlimb gait and hindlimb lameness give the appearance of hindlimb weakness. Signs occur suddenly or develop over several weeks. Chronic discospondylitis may develop if the spinal pain responds to NSAID and no further diagnostic investigations are performed.