Final answer:
Paraplegia is a specific potential postoperative complication of thoracic spinal surgery due to damage to the part of the spinal cord that can affect motor control and sensation in the lower half of the body.
Step-by-step explanation:
A potential postoperative complication specific to thoracic spinal surgery is paraplegia (C). Thoracic spinal surgeries involve operations on the part of the spine that corresponds to the chest region, containing the thoracic vertebrae. It is a high-risk area because it houses the spinal cord, which when damaged could lead to serious complications such as paraplegia. This condition entails the loss of voluntary motor control and sensation in the lower half of the body because the nerve pathways within the spinal cord have been impaired.
While other complications such as wound infection (A), urinary retention (B), and vocal cord paralysis (D) can occur after various types of surgeries, paraplegia emerges as a specific concern in the context of thoracic spinal surgery given the region's direct impact on the spinal cord.