Chevron versus transverse osteotomies in intercalary reconstructions – Lessons learned from cadaveric biomechanical study about mechanical stability and biological implications

Abstract

Background

Intercalary allograft reconstruction of long bone defects faces challenges such as nonunion and graft failure. Biomechanical stability and available bone surface area are important for allograft union and treatment success. While the transverse osteotomy is frequently used, the Chevron osteotomy may provide improved biomechanical stability and increased available bone surface area compared to the transverse technique.

Methods

This study included ten cadaveric to evaluate the biomechanical stability under axial and torsional loading.The ten tibiae were reconstructed with either the transverse (n = 5) or the Chevron (n = 5) osteotomy technique for intercalary reconstructions, each guided with 3D printed patient specific sawguides. Loading conditions were chosen to mimic peak forces occurring during normal gait. Interfragmentary motion (mm) at the osteotomy interface was measured using digital image correlation techniques. Available bone surface area (mm²) was calculated from 3D models.

Results

Under axial loading the Chevron osteotomy configuration resulted in a mean interfragmentary motion of 0.4 mm (95% CI 0.3 mm – 0.5 mm) versus 0.2 mm (95% CI 0.1 mm – 0.2 mm) in the transverse osteotomy group. Under torsional loading there was no difference observed between the Chevron and transverse osteotomy group. Available bone surface area was higher in the Chevron osteotomy group when compared to the transverse osteotomy group, with a mean of 758 mm² (95% CI 616 mm² – 900 mm²) versus a mean of 575 mm² (95% CI 491 mm² – 659 mm²)

Conclusions

Chevron osteotomies offer a theoretical biological advantage through increased surface area. However, this advantage depends strongly on precise execution and sustained interfragmentary compression across the osteotomy plane and without these conditions, the potential benefits may not be achieved.