Which fixation provides compression and osteogenesis?

• A. External fixation
• B. Kirschner wires
• C. Lag screws and dynamic compression plates
• D. Tension band wiring

Answer: (C)

Achieving interfragmentary compression across a fracture site is the key idea here, because stable, tight apposition of bone fragments promotes direct bone healing and osteogenesis. The way to get that reliable compression across the fracture line is with devices designed to actively pull fragments together as they are tightened.

Lag screws do this by design: you drill a clearance hole in the near fragment and a threaded hole in the far fragment. When the screw is tightened, the near fragment is drawn toward the far fragment, creating interfragmentary compression across the fracture. This direct compression reduces gap and micromotion, fostering bone deposition and healing.

Dynamic compression plates work similarly in principle. As the screws are tightened along the plate, the plate and screw interface converts tightening into a controlled compressive force at the fracture, maintaining stable contact between fragments and encouraging osteogenesis.

External fixation can provide stability and, in some configurations, compression, but it’s not the standard method for producing interfragmentary compression across the fracture site in the way lag screws and dynamic compression plates do. K-wires are mainly for alignment and provisional fixation without meaningful compression. Tension band wiring converts tensile forces into compression at certain fracture patterns, but it’s more pattern-specific and not the general method used to promote osteogenesis across most fractures.

So, the combination of direct interfragmentary compression and promotion of bone healing is best achieved with lag screws and dynamic compression plates.