Lumbosacral Stenosis

Patty Khuly

Summary

Lumbosacral stenosis is a painful disease that affects the spinal cord and the nerves around the area where the spinal column meets the pelvis (low down in the back near the tail, where the lumbar spine meet the sacrum at the level of the pelvis). In this multifaceted disease of dogs, the hind limbs, tail, bladder and rectum may be separately or uniformly affected, depending on the specific version of lumbosacral stenosis that afflicts them.

This disease can be the result of a degenerative or congenital (from birth) narrowing of the spinal cord.

In degenerative cases, it can happen because of chronic changes to the discs that live in between the vertebrae and provide a cushion for normal joint smoothness. It can also occur because of ligamentous changes in the area or trauma here. Osteoarthritis (arthritis) in the area can cause it, too. In rarer cases, tumors can be at fault.

For the congenital form of the disease, the space the spinal cord travels through is genetically inherited as a pathway that is smaller than it should be, thus constricting the spinal cord and the nerves that exit it at this point and beyond (towards the tail).

Swelling of the spinal cord is evident in both degenerative and congenital forms of the disease and causes most of the symptoms.

Symptoms and Identification

Older dogs who limp or are slow to rise, whose tails hang limp (sometimes only slightly so) and who suffer from incontinence of the bladder or bowels (or both) should be suspected of having the degenerative form of the disease.

Younger dogs with this condition (as young as puppies) are the most likely candidates for the congenital form.

In most cases, it’s a hard disease to identify. That’s because more commonly affected older dogs of large breeds typically already exhibit signs of arthritis that affect the hind end function and may already be incontinent due to a variety of other old-age processes. Younger dogs, by contrast, are easier to identify as a result of their normally pristine spinal cord status.

For me, the collection of all of these symptoms (sometimes just the involvement of a few) is almost certain to raise my lumbosacral stenosis suspicions. But even then, the problem can be a challenge to diagnose in older dogs who suffer similar symptoms from other degenerative diseases. It’s easy to get caught up in the other diseases and miss the bigger picture.

In either case, degenerative or congenital, X-rays, myelogram, CT (computed tomography or “CAT” scan) and/or MRI (magnetic resonance imaging) is the way to go. Board certified veterinary surgeons or neurologists are best able to handle these diagnostic details.

Treatment

This all depends on how severely the dogs are affected.

For degenerative cases where disks or OCD is involved, treatment of these conditions (through surgery, usually) is typically fruitful. Dogs may or may not, however, completely recover normal function of the area. Rapid treatment (once the process is identified) is deemed more effective in these cases.

The type of treatment can be medical or surgical.

In medical cases we defer to pain relief drugs (NSAIDs) and nutraceutical treatment (glucosamine or Adequan, usually). When it comes to surgical treatments, pain relievers and nutraceuticals are also employed, but we hope the drugs are only necessary in the short term.

Surgical treatment usually consists of a dorsal laminectomy. In other terms, the bony layer over the spinal cord is removed, freeing up some space for the cord to “decompress” so the swelling and is painful or functional symptoms can be relieved. The success rate tends to be quite high if a board-certified surgeon is employed (67-94%).

Veterinary Cost

The cost all depends on the primary or secondary effects of the disease process. If the degenerative or congenital disease leads to surgical alternatives, the costs can be large: $2,000 to $5,000 is typical for an individual surgery, depending on the underlying or resulting combination of problems (disc disease, congenital compression, OCD, etc.).

Medical treatment is usually much more manageable, at a norm of $20 to $100 a month.

Prevention

Prevention of degenerative lumbosacral stenosis is difficult but can be achieved by limiting weight gain (curbs disc disease and osteoarthritis). Severely affected degenerative patients should not be bred and any offspring shouldn’t either.

No congenitally affected dogs should be bred––ever!––regardless of the patient’s severity. This is the mainstay of prevention

References

OFA

Lenehan TM. Canine cauda equina syndrome. Compend Contin Educ Pract Vet 1983;5:941-950.

Tarvin G, Prata RG. Lumbosacral stenosis in dogs. J Am Vet Med Assoc 1980;177:154-159.

Gilmore DR. Lumbosacral diskospondylitis in 21 dogs. J Am Anim Hosp Assoc 1987;23:57-61.

Fletcher TM. Spinal cord and meninges. In: Evans HE, Miller ME, eds. Miller's anatomy of the dog. Philadelphia, Pa: WB Saunders, 1993:800-828.