What is Lumbosacral Disease?
Lumbosacral (LS) disease is a term for several conditions that affect the spine in the lumbosacral region (where the pelvis meets the spine). Some causes include nerve compression by a bulging intervertebral disc or other soft tissues and instability between the lumbar vertebrae and sacrum. Aging can result in dehydration and degeneration of the intervertebral disc located between the last lumbar vertebrae and the sacrum, causing it to bulge and compress nerves. This results in narrowing of the vertebral canal and the exit holes between the vertebrae (the vertebral foramen) and is termed ‘stenosis’.
What breeds are commonly affected?
Larger, male dogs are more commonly affected than smaller dogs. German Shepherd Dogs appear to be particularly predisposed.
What are the signs of LS disease?
Lower back or hind limb pain is the main clinical sign that is observed. Animals affected by this condition often are reluctant to jump up onto objects or climb stairs, and often have difficulty when getting up from a lying position. Vocalisation as though in pain can also be seen. Urinary and/or faecal incontinence, hind limb lameness, and reduced tail movement are less common but can also be seen with lumbosacral disease
How is LS disease diagnosed?
A complete neurological examination will enable the surgeon to perform neurolocalisation; that is to determine the location in the spinal cord that is affected. Radiographs of the spine are performed to help identify and rule out other causes but are not good at assessing for LS disease. Advanced imaging, including CT and MRI is normally recommended. An MRI scan is of greatest benefit in diagnosing LS disease and will identify the location and extent of any soft tissue compression of the nerves in the lumbosacral spine.
How is LS disease treated?
Conservative Management:
- This involves strict rest (absolutely no exercise initially – lead-walking for toileting purposes only, followed by a slow but gradual increase in the length of exercise), along with a combination of anti-inflammatory medications, analgesia, muscle relaxants and neuropathic agents
- If your pet is overweight, a restricted diet will be recommended to promote weight loss
- Conservative management is often attempted initially in patients exhibiting their first episode of pain, but is not suitable for animals demonstrating severe neurological deficits
- Approximately 50% of dogs can have a good outcome with this management
- Prolonged exercise restriction may be required; up to 2-4 months in some cases
- Recurrences may occur once the patient is allowed to return to normal activity Non-Invasive Procedures:
- As an alternative to surgery when medical management is not proving to be effective, treatment can be attempted with epidural administration of steroid medication and local anaesthetic
- Treatment generally consists of three epidural injections; with the second and third injections performed at 2 and 6 weeks after the first
Surgical Management:
- Surgical intervention is indicated when your pet is in moderate to severe pain, or if they are exhibiting neurological deficits
- A number of different surgical approaches are available and include a dorsal laminectomy (removal of the top of the spine over the affected area), foramenectomy (enlargement of the exit holes between the bones, which are called the vertebral foramen), often both performed in conjunction with a discectomy (removal of the affected disc) or other soft tissues that are compressing the spinal nerves
- In some cases, if the stability of the vertebrae is compromised, a stabilisation procedure may need to be performed to prevent excessive movement of the lumbosacral bones
What is the prognosis for my pet?
The majority of patients will respond well to medical management or non-invasive treatments and will be able to return to full exercise and stop all medications. However there is always the potential for recurrence. Most patients undergoing surgery respond well when performed in conjunction with appropriate post-operative physiotherapy and rehabilitation, but can also suffer a recurrence of back pain.