Axial and Rotational Malreduction (Golf Club Deformity) in Distal Femur Fractures

Area of Science:

• Orthopedic surgery
• Biomechanical engineering
• Anatomy

Background:

• Supracondylar distal femur fractures are complex injuries.
• Current fixation methods using lateral femoral locking plates can lead to malreduction.
• A mismatch between plate design and native femur anatomy may contribute to fixation errors.

Purpose of the Study:

• To quantify malreduction in supracondylar distal femur fractures fixed with standard lateral femoral locking plates.
• To investigate if anatomical mismatch between the distal femur and plate design causes malreduction.
• To evaluate the effect of modified plate geometry on reducing malreduction.

Main Methods:

• Simulated OTA/AO 33A fractures in 7 cadaver femurs.
• Applied lateral distal locking femoral plates with standard (group 1) and externally rotated (10 degrees, group 2) anterior flanges.
• Used a motion capture system to measure articular segment translation and rotation.
• Analyzed 3D scans of 800 femurs to define lateral femoral condyle anatomy.

Main Results:

• Standard plate application (group 1) resulted in significant medial translation (17 mm) and external rotation (12.2 degrees).
• Modifying plate geometry (group 2) improved medial translation by 46% and external rotation by 80%.
• The average posterior-anterior inclination of the distal femur condyle is 16.5 degrees.

Conclusions:

• Anatomical plate application leads to significant malreduction in distal femur fractures.
• Modifying plate design to accommodate the lateral distal femur's slope partially corrects deformity.
• Further research is needed to optimize fixation techniques, considering the natural condylar inclination.