Stability of the offset V-osteotomy. Test jig development and saw bone model assessment

Area of Science:

• Orthopedic surgery
• Biomechanics
• Foot and ankle reconstruction

Background:

• Offset V-bunionectomy is a surgical technique for hallux valgus repair.
• Both Kalish and Vogler variations feature a dorsal arm, with the Kalish having a more distal osteotomy apex.
• Understanding factors influencing weight-bearing stability is crucial for surgical success.

Purpose of the Study:

• To investigate the impact of pin orientation and osteotomy apex location on the weight-bearing stability of offset V-bunionectomy techniques.
• To compare the biomechanical strength of the Kalish and Vogler bunionectomy procedures.

Main Methods:

• Bone models were subjected to load-to-failure testing using a materials testing machine.
• A custom jig assembly was designed and utilized to enhance data consistency.
• Comparison of biomechanical performance between Kalish and Vogler osteotomies with varying Kirschner wire orientations (plantar vs. dorsal).

Main Results:

• Statistically significant differences in strength were observed between the surgical techniques and pin orientations.
• The Kalish osteotomy exhibited greater strength compared to the Vogler procedure.
• Plantarly directed Kirschner wire orientation resulted in superior strength for both osteotomy types.

Conclusions:

• The Kalish technique offers enhanced biomechanical stability over the Vogler procedure for hallux valgus repair.
• Plantar Kirschner wire placement provides superior fixation strength compared to dorsal placement in offset V-bunionectomies.
• Optimizing pin orientation and understanding apex location are critical for improving surgical outcomes in hallux valgus correction.