At some time or other, all equine clinicians will come across cases that have some indication of a morbid nervous system lesion, but no definitive proof can be obtained. Often, these cases are suspected to be suffering from conditions such as a painful musculoskeletal disorder, a neuromuscular movement disorder, a behavioral problem such as belligerency or laziness, or thoracolumbar vertebral (back) disease. Such patients may show one or more of the signs listed in Table 2.6. Examples of forms of frantic behavior have been associated with a strong suspicion of exposure to nettles or poison ants, but in these situations the signs usually abate with time. A few of these unusual syndromes are discussed in the later sections of Part II.
Initial plan
Following consideration of anatomic and etiologic diagnoses, an initial plan must be devised. This will include the use of ancillary aids to help rule in and rule out certain disease processes, a therapeutic plan, and a plan for client education, including economic advice, herd health management, and prognostic considerations.
Table 2.6 Examples of syndromes in which an organic neurologic lesion may be suspected but is usually not proven
| Prominent toe dragging | Prominent sinking with dorsal lumbar pressure |
| Intermittent and unusual lameness | Throwing to the ground when saddle applied |
| Shivering | Rearing violently when first ridden |
| Stringhalt‐like movements | Extreme difficulty in rising |
| Hyperreflexic movements | Localized hypertonia and tremor |
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