Which type of splint is specifically used for femoral shaft fractures to reduce muscle spasm?

A traction splint is specifically designed to stabilize and immobilize femoral shaft fractures by applying longitudinal traction. This technique helps to reduce muscle spasm, which can be a complication following a femoral fracture. The traction is achieved by using a system that pulls on the limb, effectively aligning the fractured bone segments and alleviating the tension created by surrounding muscles. This is crucial because muscle spasms can exacerbate the injury and lead to further displacement or complications.

In medical settings, traction splints are particularly beneficial because they allow for stabilization while minimizing pain and reducing the risk of further injury until definitive treatment can be administered. The other options do not fulfill this specific role in treating a femoral shaft fracture. For instance, pneumatic splints provide stabilization but do not deliver the same traction effect necessary for properly managing muscle spasm in this context. Flail chest is an injury related to rib fractures and is not relevant to femoral shaft fractures. A greenstick fracture refers to a type of bone fracture often seen in children, which differs fundamentally from the situation with a femoral shaft fracture. Hence, the traction splint stands out as the appropriate choice for this scenario.