Military working dogs present a unique population of dogs in which a greater degree of return of function is required after
surgery in order for them to perform their high-activity work. Consequently, several studies have evaluated the outcome of
surgical intervention in military dogs.32,41,42 Overall successful outcome ranged from 41% to 78% of military working dogs being able to return to normal function.32,41,42 Age and severity of neurologic deficits were prognostically significant factors affecting outcome postoperatively.42 Dog older than 9 years of age or dogs with severe deficits (paresis, muscle atrophy, and urinary or fecal incontinence) were
unlikely to return to work activity.42
CONCLUSION
In summary, lumbosacral disease is a syndrome rather than a disease. The signs consistent with lumbosacral syndrome are the
result of dysfunction of the L7, sacral, and caudal spinal cord segments or spinal nerve roots. Consequently, patients present
with varying degrees of sensory and motor dysfunction to the pelvic limbs. While many conditions result in signs of lumbosacral
disease, degenerative lumbosacral stenosis is relatively common. Affected patients can present with paraparesis, urinary and
fecal incontinence, hyperesthesia, and abnormal tail function. Degenerative lumbosacral stenosis is the result of Hansen's
Type II intervertebral disk disease, hypertrophy of the dorsal longitudinal ligament and interarcuate ligament, and degenerative
changes of the articular facets at the L7-sacral articulation.
Various tests have been used to diagnose degenerative lumbosacral stenosis. MRI is now considered the premier method of imaging
the lumbosacral vertebral column. Despite advanced imaging procedures, clinical signs do not always correlate with imaging
findings. So care must be exercised when interpreting imaging findings. Treatment of affected dogs includes both medical and
surgical procedures. The prognosis depends on several factors, including age and degree of dysfunction. Overall, many affected
dogs can benefit from therapeutic interventions.
Marc Kent, DVM, DACVIM (neurology, internal medicine) Department of Small Animal Medicine and Surgery College of Veterinary Medicine The University of Georgia Athens, GA 30602
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