Far cortical locking enables flexible fixation with periarticular locking plates.

Area of Science:

• Orthopedic biomechanics
• Surgical implant technology

Background:

• High stiffness in periarticular locked plating can impede fracture healing.
• Far cortical locking (FCL) screws show promise in reducing stiffness for diaphyseal fractures.

Purpose of the Study:

• To evaluate the biomechanical effects of using FCL screws for diaphyseal fixation within periarticular plating constructs.
• To determine if FCL reduces construct stiffness and increases interfragmentary motion without sacrificing strength.

Main Methods:

• A biomechanical study using 22 paired femurs with distal femur fractures stabilized by periarticular locking plates.
• Comparison between standard locked plating (LP) and FCL fixation using MotionLoc screws.
• Assessment of construct stiffness, durability under dynamic loading, and residual strength.

Main Results:

• FCL constructs exhibited 81% lower initial stiffness compared to LP constructs.
• FCL constructs generated significantly more interfragmentary motion, promoting parallel motion.
• Residual construct strength was comparable between LP and FCL groups after cyclic loading.

Conclusions:

• FCL screws effectively reduce stiffness and induce beneficial interfragmentary motion in periarticular plating constructs.
• FCL fixation maintains construct strength, suggesting its potential to enhance fracture healing via callus formation.