At which level of spinal cord injury is the risk for autonomic hyperreflexia greatest?

The risk for autonomic hyperreflexia is greatest in individuals with spinal cord injuries at the T6 level or higher, and it can begin to be a concern even at T7. This condition occurs due to an imbalance in the autonomic nervous system, particularly when there is an injury that disrupts the communication between the sympathetic and parasympathetic systems. In injuries occurring at the thoracic spinal levels, particularly around T6 to T8, the risk is heightened because the sympathetic outflow can become overly excitable, especially in response to stimuli below the level of injury that the brain cannot regulate.

When the injury occurs at T7, it is close enough to this critical threshold that individuals may experience significant autonomic dysregulation, making it the correct choice in identifying the level with the greatest risk. Higher levels of injury, such as T4, may also pose risks, but the threshold level is generally considered to be T6, making T7 a key focus. Lower spinal levels, such as C8 or T10, would not carry the same risk since their impact on autonomic functions is less pronounced compared to T6 to T8 injuries.