Establishment of Subtrochanteric Fracture in Pre-Clinical Animal Model

Area of Science:

• Orthopedic Surgery
• Biomaterials Science
• Regenerative Medicine

Background:

• Subtrochanteric femur fractures are a significant subset of hip fractures, yet research remains limited.
• Understanding the unique healing mechanisms of the subtrochanteric region is critical for effective treatment.

Purpose of the Study:

• To develop a reproducible and clinically relevant rabbit model for open subtrochanteric femur fractures.
• To establish a foundation for future investigations into fracture healing and biophysical interventions at this site.

Main Methods:

• An open osteotomy model was created in 32 New Zealand white rabbits at the subtrochanteric femur region.
• Customized internal fixation using a 3D printed titanium compression plate with locking screws was employed.
• Fracture healing was assessed over six weeks using radiography, MicroCT, and histomorphometry.

Main Results:

• The model demonstrated successful fracture healing progression observed radiographically.
• MicroCT analysis indicated increased callus volume by 42 days post-surgery.
• Histomorphometry revealed bone remodeling with an elevated osteocyte count.

Conclusions:

• A reliable rabbit model for open subtrochanteric femur fractures was successfully established.
• The model utilizes advanced 3D printed titanium internal fixation for stability.
• This model provides a platform for exploring biophysical stimulation to enhance fracture healing.