Classification of vascularized fibular flap hypertrophy based on X-ray evaluation

Area of Science:

• Orthopedic surgery
• Regenerative medicine
• Biomaterials science

Background:

• Vascularized fibula flaps are crucial for reconstructing long bone defects.
• Hypertrophy of these flaps can impact long-term outcomes.
• Classifying hypertrophy patterns is essential for predicting flap maturation.

Purpose of the Study:

• To analyze and classify hypertrophy in vascularized fibula flaps used for tubular bone defect reconstruction.
• To identify factors influencing fibular flap hypertrophy.
• To establish a classification system for fibular hypertrophy.

Main Methods:

• Retrospective review of 33 patients undergoing vascularized fibula flap reconstruction.
• Analysis of anteroposterior (AP) and lateral X-ray measurements at an average of 52 months post-surgery.
• Calculation of hypertrophy percentage based on initial and final flap thickness.

Main Results:

• Four distinct modes of fibular hypertrophy were identified: type 0 (none), type 1 (limited), type 2 (stress fracture-induced), and type 3 (enhanced by peripheral bone production).
• Flap hypertrophy patterns varied based on vascularity, stress, reconstruction site, and periosteal sleeve retention.

Conclusions:

• Fibular hypertrophy is a complex phenomenon with diverse modes of presentation.
• Predicting final flap hypertrophy is possible by assessing initial factors such as vascularity and stress.
• This classification aids surgeons in managing and predicting outcomes of fibular flap reconstructions.