New Lag Screw Design for Maxillofacial Trauma

Lag Screw are a type of screw that has large hex heads to allow it to bind to the material it is fastening to. They can withstand significant stress and are often used on construction projects. Lag screws are a great choice for putting together doors and railroads because of their durability.

In the management of maxillofacial trauma, lag screw placement is commonly employed in rigid fixation. However, the success of this method depends on proper screw positioning: the screw must be inserted perpendicular to the fracture line when it is sagittal and at right angles to the fracture line when it is oblique. Incorrect screw positioning will result in imprecise reduction, complications, and instability.

To prevent these problems, we propose a new lag screw design: a helical blade with threads only on the ends and a head devoid of threads. This configuration allows the screw to compress both the far and near cortices of a multifragmentary fracture in order to achieve rigid fixation and stability.

The new lag screw is also designed to facilitate easy driving by a drill. This is achieved by a six lobe drive style that reduces cam-out, a larger head surface area that eliminates the need for flat washers, and a high corrosion resistant surface treatment. Additionally, a unique feature of the lag screw is its ability to deliver orthobiologics (BoneSync cement, autologous blood products, etc.) to the area of interest prior to screw seating.