Will a good orthopedic pillow for neck injuries help sleep me better?

Depends: I would first assess the severity of your neck injury to determine what position would be best to sleep in. Consult a orthopedic surgeon. Generally, having a semi firm pillow that keeps your neck aligned with your spine is recommended.

Possibly: They are pretty expensive, but people really seem to be happy with the memory foam ones. Of course it depends on the pathology, but for general stiffness, a memory foam pillow can be very helpful.