Does Far Cortical Locking Improve Fracture Healing in Distal Femur Fractures: A Randomised, Controlled, Prospective...

Area of Science:

• Orthopedic surgery
• Biomechanical engineering
• Bone healing research

Background:

• Mechanical factors critically influence bone healing, including stability, interfragmentary motion, strain rate, and loading direction.
• Far cortical locking (FCL) screws represent a novel design intended to enhance bone healing by regulating fracture motion.
• Understanding the biomechanical interplay in fracture fixation is essential for improving patient outcomes.

Purpose of the Study:

• To compare the efficacy of far cortical locking (FCL) screws versus standard locking (SL) screws in treating distal femur fractures.
• To evaluate the impact of screw design on radiographic bone healing and time to union.
• To investigate the role of working length in fracture healing outcomes.

Main Methods:

• A randomized controlled prospective multicenter trial involving 21 patients with distal femur fractures.
• Fractures were treated using either FCL or SL screws in conjunction with an NCB plate.
• Bone healing was assessed using the Radiographic Union Scale in Tibia (RUST) and time to union.

Main Results:

• Patients treated with SL screws exhibited a longer mean working length (6.1) compared to those with FCL screws (3.9).
• The mean RUST score at 6 months did not significantly differ between SL (8.0) and FCL (7.3) groups (p > 0.05).
• Fractures fixed with SL plates demonstrated significantly faster healing times (mean 6.5 months) than those with FCL plates (mean 9.9 months) (p < 0.05).

Conclusions:

• Standard locking plates were associated with longer working lengths and accelerated healing times compared to FCL constructs.
• These findings underscore the importance of achieving adequate working length for successful fracture healing.
• The choice of screw design may be less critical than ensuring appropriate biomechanical conditions for bone union.