Lumbosacral Stenosis (Cauda Equina Syndrome) in Dogs

Much like ours, the dog’s spine has disks between the bones that act as shock absorbers between adjacent vertebrae. The spinal cord (a bundle of nerve fibers) passes through a large canal (vertebral column) which protects it from injury. The spinal cord, which is shorter than the vertebral column, ends at the lower back.  The nerves to the bladder, rectum, tail and limbs extend off the end of the spinal cord, out through the vertebral column. The area where the nerves extend off the end of the spinal cord resemble a horse’s tail.  This is why this particular area is called the cauda equina. The “cauda equina” is Latin for horse’s tail.

Lumbosacral stenosis usually occurs in large breeds.  Clinical signs usually occur between 3 – 7 years of age. Lumbosacral stenosis (cauda equina syndrome) is also referred to as lumbosacral instability, lumbosacral spondylolisthesis and lumbosacral nerve root compression.

Lumbosacral stenosis in dogs is a condition that causes the nerves of the lower back (cauda equina) to be compressed as they leave the spinal canal. The pressure on the nerves causes nerve injury. This condition is extremely painful.

Symptoms will vary depending on the severity of nerve damage. Symptoms may include:

• Difficulty getting up and down from furniture or the car
• Difficulty posturing to defecate or urinate
• Unable to climb stairs
• Lameness of one or both hind legs
• Whines/yelps when trying to get up
• Muscle loss to one or both hind legs
• Leakage of urine
• Cries out when lower back is petted
• Shuffling gai
• Scuffed toes
• Chews or bites at pelvic area, tail or hind legs because of tingling sensation to the area

• Congenital - The dog was born with the condition
• Arthritis - Causes thickening of the joints of the spinal cord.
• Herniation of the lumbar intervertebral disks
• Thickening of the ligaments within the spinal canal
• Abnormal growths - Tumor growing on the lower spinal cord
• Partial dislocation - Spinal bones malalignment

The veterinarian may want to go over the patient’s medical history.  He will want to know what symptoms you have observed and when did they begin. If the dog is lying down he may want to see him get up and walk around.

The veterinarian will then perform a physical examination of the dog.  He will take the patient’s weight, pulse and blood pressure.  The veterinarian may palpate the muscle tone of both limbs.  Hind leg manipulation can help determine which positions are painful.  The veterinarian will test your dog’s reflexes.  Consideration will be made as to the extent of pain this may cause. The veterinarian may recommend taking a complete blood count on the patient.  

X-rays of the spine and pelvic area will be recommended.  If he suspects lumbosacral stenosis he may want the patient to have a myelogram.  This is a specialized x-ray that uses an injection of contrast dye to find abnormalities to the spinal cord, spinal canal, nerve roots and surrounding tissue. Your dog  will need to have general anesthesia for this procedure.

Treatment of lumbosacral stenosis (cauda equina) in dogs may be treated nonsurgically or surgically depending on the severity of the condition.  In mild cases of lumbosacral stenosis, the patient will be treated with restricted limits of movement/exercise.  Your dog may be prescribed pain medication and an anti-inflammatory such as prednisone. Once he is feeling better, hydrotherapy may be recommended. Some dogs may also respond to epidural steroids injections.

Dogs with more severe cases of lumbosacral stenosis or patients who are diagnosed with a tumor will be referred to a veterinary orthopedic surgeon.  The surgeon will discuss with you which is the best surgical procedure for your dog.  In some cases, the bones are fused together in a “normal” position. Another surgical procedure that can be performed, also known as decompression surgery, is a laminectomy.

Dogs that undergo surgery will have to be confined for 2-4 weeks after surgery.  The surgeon will provide you with post-operative instructions.  The patient will be prescribed pain medications and anti-inflammatory medications.  He may also be placed on antibiotics as a preventative to an infection. An elizabethan collar (cone) should be worn by the dog so that he does not lick or bite at the incision. Dogs that undergo surgery usually have a good prognosis.  Dogs that still having difficulty urinating may need help; manually expressing the bladder of urine will be required.  The patient will need follow up visits to monitor his progress and to remove sutures.

Canines that are treated medically will need to be monitored for the progression of the condition and for any side effects from the medications. They will need to remain on anti-inflammatory and intermittent pain medications.  Hydrotherapy and acupuncture may also help the patient with the pain caused by lumbosacral stenosis.