A nurse is caring for a client who is postoperative placement of a halo vest to manage a cervical vertebral fracture. Which of the following actions should the nurse take?

The correct answer is C: Reposition the client using a turning sheet. This action is important to prevent complications such as pressure ulcers and skin breakdown. Turning the client using a turning sheet helps distribute pressure evenly and prevents prolonged pressure on any one area, which is crucial for clients with cervical vertebral fractures. Encouraging flexion and extension of the neck (choice A) can be harmful and should be avoided to maintain stability. Assessing the pin sites for infection once every other day (choice B) is important but not the immediate priority for this client. Tightening the screw on the halo device (choice D) should be done as per healthcare provider's instructions, not every 48 hours.