How could a paramedic deal with a compound shin fracture?

Stabilization. If the skin is intact, the pre-hospital treatment for any extremity fracture is stabilization. Ambulances typically carry either padded-board splints and/or vacuum splints; which can be used to prevent the leg from moving and causing further injury. If the skin is broken, the leg is immobilized in a similar fashion with care given to control bleeding. Pain medication may also be given as needed.
Splinting. All fractures should be kept immobized until more definitive care can be obtained.