Intervertebral Disc Disease (IVDD) Type I

NeurologyCanineNew

Key Points

Type I IVDD (Hansen Type I) is an acute intervertebral disc extrusion that occurs when degenerate nucleus pulposus material ruptures through the annulus, enters the vertebral canal and compresses the spinal cord
Most common in young-middle-aged chondrodystrophic dogs
Neurological signs depend on where along the spinal column the lesion is
- Cervical lesions: neck pain, tetraparesis and increased reflexes
- Thoracolumbar lesions: pelvic limb ataxia / paresis / plegia with normal thoracic limbs
MRI is the best diagnostic tool as it can localise the lesion and assess the spinal cord parenchyma
Conservative treatment may be considered in mild, ambulatory cases, but surgical decompression is recommended if patients are non-ambulatory, progressive or severely-affected
Despite treatment and recovery, extrusions can recur as the underlying problem of disc degeneration cannot be cured

Differential Diagnoses

Acute non-compressive nucleus pulposus extrusion (ANNPE)
Fibrocartilaginous embolism (FCE)
Discospondylitits
Steroid-responsive meningitis-arteritis (SRMA)

Educational content only. This factsheet is for general veterinary education and is not a substitute for professional veterinary advice, diagnosis, or treatment. Not for use in an emergency — contact a veterinarian or emergency service. Full disclaimer →