A 32-year-old male involved in a high-speed motor vehicle collision presents with severe back pain, inability to move his legs, and diminished sensation below the umbilicus. What is the most appropriate initial immobilization technique to prevent further injury in this patient?
Apply a spinal backboard and cervical collar
Utilize a traction splint to align the spine
Use manual traction on the lower extremities
Place a pelvic binder to stabilize the region