Lumbosacral

Lumbosacral disease is an umbrella term used to describe a condition of the spine at the level of the lumbosacral junction. Usually the condition arises in middle to older aged animals. Certain breeds such as German Shepherds being over represented. In the majority of cases degeneration of the lumbosacral intervertebral disc results in narrowing of the spinal canal at the lumbosacral junction usually from protrusion of the degenerate disc. Compression of the nerve roots (cauda equina) as they cross the lumbosacral junction results in pain and discomfort and in severe cases hind limb neurological deficits, urinary and faecal incontinence.

In the majority of cases clinical signs are related to hind limb stiffness, and reluctance to jump and exercise. Often a unilateral lameness may be present due to asymmetrical compression of the nerve roots and in 80% of cases pain is present on firm palpation of the lumbosacral junction. The presence of neurological deficits such as hind limb weakness, reduced proprioception (spatial awareness e.g. knuckling), urinary and faecal incontinence carries a poor prognosis.

Although radiographs often show degenerative changes at the lumbosacral junction this is not uncommon incidental finding in normal dogs. Confirmation of diagnosis requires MRI in order to visualise the nerve roots at the level of the lumbosacral junction, which primarily involves the L7 nerve root, the major contributor to the sciatic nerve. Inflammation and compression of the L7 nerve root primarily is the underlying cause of pain and discomfort and is similar to sciatica in humans.

Treatment is either conservative or surgical with a conservative approach being adopted in the first instance in most cases. This requires extended periods of restricted levels of activity, non steroidal anti-inflammatory medication and usually neuroleptanalgesics such as Gabapentin or Tramadol. Those cases that have severe extrusions or fail to respond to conservative management may be considered appropriate for decompressive dorsal laminectomy.