Spinal cord diseases in cats can be quite challenging. The journey begins with a reluctant patient, moves through the complicated process of interpreting neurological exams, and concludes with the vast array of potential diseases that may be responsible for the observed symptoms. While even a board-certified neurologist may find it difficult, there are some insights we can offer that could be beneficial.
Tips on neurologic examination in cats:
Cats often communicate their reluctance by saying, “I’m not interested in your activities, and I won’t engage.” Nevertheless, there are strategies to encourage their participation without them realizing it or with minimal cooperation. For those needing a refresher on the neurological examination, refer to “The Neurological Examination of the Cat” by Laurent Garosi in the Journal of Feline Medicine and Surgery, 2009 Volume 11. We would like to highlight a few important points:
- Gait Analysis – This aspect is crucial in cats. To save time, allow the cat to walk around the room while you gather the owner’s history. Divide the cat’s assessment into three sections: the head, the thoracic limbs, and the pelvic limbs, including the tail. Evaluate each part individually before integrating your findings. Pay attention to the tail’s movement: does it drag, or does it remain upright, aiding balance like in a vestibular cat?
- Postural Reactions – Based on our experience, cats dislike hopping and are not fond of having their feet touched. The most effective tests to conduct include wheelbarrowing, extensor postural thrust, and particularly tactile placing on a table. Consistency is vital, as one abnormal extensor postural thrust among four normal attempts is not significant.
- Cranial Nerves – Along with routine tests, don’t forget to conduct a fundic exam. Since infectious diseases are among the most common causes of spinal issues in cats, this examination can be very valuable.
- Spinal Reflexes and Appendicular Tone/Muscle Size – These assessments are best performed with the cat lying on its back between your legs or by having a technician support the cat so its pelvic limbs hang freely for examination.
- Spinal Pain – This should always be the last test performed on cats, as they can be easily agitated. It’s essential to ask the owner how their pet has reacted to back touch in the past. Many cats are simply hyperreactive rather than hyperesthetic during thoracolumbar spinal palpation.
- Orthopedic Versus Neurologic Disease – The more predictable the abnormal movement, the more likely it is to be orthopedic in nature. Cats that hold their limbs up typically have orthopedic issues, while those struggling to keep their heads elevated are more likely to have neurological problems.
Keep in mind that neuroanatomic localization is crucial, as it allows you to use textbooks to assist in creating your differential diagnosis list. If you’re unsure about the location of the problem, this is the ideal time to refer the case. Accurately localizing the issue helps guide the right diagnostic approach, saves time, and reduces frustration for the owner.
Once you have determined the neuroanatomic localization, you can begin to identify the most probable differential diagnoses. There are a few approaches to consider this, starting with categorizing them from most to least likely.
- Infectious/Inflammatory Conditions
- Neoplasia
- Traumatic Injuries (such as fractures, luxations, and intervertebral disc disease)
- Congenital/Inherited Disorders (e.g., storage diseases)
- Vascular Disorders
Alternatively, you can categorize them by specific diseases:
- Feline Infectious Peritonitis
- Lymphosarcoma
- Vertebral Tumors (with osteosarcoma being the most common)
- Traumatic Injuries (such as fractures and luxations)
- Vascular Disorders
Alternatively, you can classify them by age groups:
Prevalence:
- Under 2 years old:
- Feline Infectious Peritonitis
- Storage Disease
- Bacterial Infections
- Trauma
- Lymphosarcoma
- Ages 2-8 years old:
- Feline Infectious Peritonitis
- Lymphosarcoma
- Vertebral Neoplasia
- Cryptococcus
- Intervertebral Disc Disease
- Over 8 years old:
- Vertebral Neoplasia
- Vascular Disease
- Lymphosarcoma
- Other Neoplasia
- Intervertebral Disc Disease
By utilizing your history, clinical signs, and some prevalence guidelines for diseases, you can develop your differential diagnoses. Below is some information on feline diseases that you may not be as familiar with.
Intervertebral Disc Disease: This condition can affect cats, particularly in the thoracolumbar or lumbosacral regions, and should be ruled out in cervical cases. Typically seen in cats aged 8 to 10 years, signs include back pain, discomfort during tail manipulation, and paraparesis/plegia. The prognosis is favorable (around 90%) if sensation is intact and surgery is performed.
Vascular Disease: Multiple spinal cord levels may be affected, especially in the cervical region. Cats may struggle to hold their heads up and exhibit tetraparesis/plegia with increased limb tone/reflexes. Fibrocartilaginous embolisms are rare, so it’s important to investigate other causes like hyperthyroidism. If addressed, the prognosis is similar to dogs, with about 75% having favorable outcomes. These lesions differ from feline aortic thromboembolism, which has a worse prognosis (~25% favorable outcome).
Neoplasia: Lymphosarcoma is the most common spinal tumor in cats, accounting for up to 40%, followed by osteosarcoma. It often affects the thoracolumbar and lumbosacral regions. Pain is not always present, and signs tend to be symmetric. Younger cats are more likely to have lymphosarcoma, with around 50% testing positive for FeLV. The prognosis is generally poor, while spinal cord meningiomas have a better prognosis for recovery and two-year survival.
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