What spinal cord levels are involved if a tetraplegic horse can raise its head?

What spinal cord levels are involved if a tetraplegic horse can raise its head?

• A. C1-C3
• B. C7-T1
• C. C4-C6
• D. T2-T5

Answer: (B)

Raising the head relies on muscles of the neck that are controlled by the upper cervical spinal cord segments. In a tetraplegic horse, all four limbs are affected because the injury involves the cervical region, but the ability to lift the head depends on which cervical segments remain functional. If the lesion is at the C7–T1 level, the neck muscles that elevate the head (supplied by the higher cervical segments, roughly C1–C6) can still function, so the horse can still raise its head. At the same time, this level is enough to disrupt the brachial plexus pathways that affect the limbs, resulting in tetraplegia. Higher cervical injuries (like C1–C3 or C4–C6) would more severely compromise neck musculature and make head-raising difficult or impossible, whereas the T2–T5 region wouldn’t typically produce tetraplegia. Therefore, C7–T1 is the level that best fits a tetraplegic horse that can still raise its head.

Raising the head relies on muscles of the neck that are controlled by the upper cervical spinal cord segments. In a tetraplegic horse, all four limbs are affected because the injury involves the cervical region, but the ability to lift the head depends on which cervical segments remain functional.

If the lesion is at the C7–T1 level, the neck muscles that elevate the head (supplied by the higher cervical segments, roughly C1–C6) can still function, so the horse can still raise its head. At the same time, this level is enough to disrupt the brachial plexus pathways that affect the limbs, resulting in tetraplegia.

Higher cervical injuries (like C1–C3 or C4–C6) would more severely compromise neck musculature and make head-raising difficult or impossible, whereas the T2–T5 region wouldn’t typically produce tetraplegia. Therefore, C7–T1 is the level that best fits a tetraplegic horse that can still raise its head.