Welcome to the latest edition of the BVNS Neurotransmitter.

Suki Hall, a one-year-old, female spayed, Yorkshire Terrier who presented to BVNS Springfield after an inability to walk on her back legs.

EXAM FINDINGS

Suki became non-ambulatory over just a few hours, with severe pain that slowly subsided. By the time we saw her at BVNS Springfield, she was non-ambulatory paraparetic with just a little bit of motor in her pelvic limbs. Her reflexes were normal in all four limbs and she had normal proprioception in the thoracic limbs but absent placement and hopping of the pelvic limbs. We could not elicit a cutaneous trunci reflex anywhere along her back. Her problem was localized to the T3-L3 region of the spinal cord and differentials discussed included IVDD, FCE and spinal GME.

Based on Suki’s history and clinical signs, where would you localize?

Her problem was localized to the T3-L3 region of the spinal cord and differentials discussed included IVDD, FCE and spinal GME.

DEFINITIVE DIAGNOSIS

Pre-anesthetic blood work was run, which was normal. MRI of the spine revealed a reduced volume of nucleus pulposus at L1-2 with focal T2w hyperintensity spanning from caudal-vertebral body T13 to mid-L1 vertebral body. There was minimal compression of the spinal cord (see MRI figures above). Suki was diagnosed with an acute non-compressive nucleus pulposus extrusion (ANNPE) of the L1-2 intervertebral disc.

WHAT IS ANNPE?

ANNPE is defined as a sudden extrusion of non-degenerate disc material from the nucleus of the intervertebral disc. With ANNPE there is minimal compression of the spinal cord but because it comes out of the disc space with a significant amount of force, concussive damage is done to the spinal cord. Prognosis varies depending on which study you read, from 66-100% recovery, and correlates to the amount of concussive damage done to the spinal cord. ANNPE signs can be lateralized and can cause both urinary and fecal incontinence. A recent paper showed that treating with an appropriate NSAID significantly decreased the risk of long term urinary incontinence.

TREATMENT

Suki was sent home on meloxicam, gabapentin, and diazepam with instructions for strict rest. Strict rest should be instituted, as with any disc herniation, to prevent further disc extrusion that could cause further neurologic decline. This can be compared to treatment for an FCE (another type of non-surgical spinal cord injury), where pain management is less necessary and strict rest is not critical because we aren’t worried about triggering recurrences.

Over the next 4-8 weeks, Suki grew stronger and stronger and is now doing amazing. Her family is keeping a close eye on her and decreasing the amount of dynamic leaping she is doing, but she has an awesome quality of life and is her happy, adorable self again.

Suki, 4 weeks into Recovery:

Suki, 8 weeks into Recovery:

TAKE HOME POINTS FROM DR. BARKER

1. Quickly becoming a “down dog” doesn’t have to be life-threatening and recovery doesn’t always require surgery.

2. An MRI can help determine if surgery should be considered and what medical management is most appropriate.

3. Strict rest and NSAIDs are important treatment components for ANNPE.

Thank you Dr. Mazur and Clocktower Animal Hospital of Herndon, VA for referring this case!

Click HERE for a PDF version of this publication.

Selected References

1. De Decker et al. Acute Herniation of Nondegenerate Nucleus Pulposus Acute Noncompressive Nucleus Pulposus Extrusion and Compressive Hydrated Nucleus Pulposus Extrusion. Vet Clin Small Anim 48, 95–109. 2018

2. Mari et al. Outcome comparison in dogs with a presumptive diagnosis of thoracolumbar fibrocartilaginous embolic myelopathy and acute non-compressive nucleus pulposus extrusion. Veterinary Record, 10.1136/vr.104090. 2017

3. Mari et al. Predictors of urinary or fecal incontinence in dogs with thoracolumbar acute non-compressive nucleus pulposus extrusion. JVIM, 33:2693-3000. 2019