What is the primary cause of anterior spinal artery syndrome?

The primary cause of anterior spinal artery syndrome is often associated with reduced blood flow to the anterior part of the spinal cord, which is primarily fed by the anterior spinal artery. A flexion injury can lead to such vascular compromise. This type of injury may cause damage to the spinal arteries due to significant movement or displacement of spinal structures, resulting in ischemia in the anterior part of the spinal cord. This can lead to a characteristic clinical presentation of anterior spinal artery syndrome, which includes loss of motor function and temperature sensation below the level of the injury, while preserving proprioception and vibratory sense.

While traumatic hyperextension injury, spinal cord compression from a tumor, and penetrating spinal cord injury all pose risks to spinal cord integrity, they are not the primary causes of anterior spinal artery syndrome in the same way as a flexion injury. Generally, these other injuries might lead to different kinds of spinal cord syndromes or complications but do not specifically align with the classic cause of anterior spinal artery syndrome. The unique mechanism of flexion injury in compromising the anterior spinal circulation distinguishes it in this context.