Tendon transfer fixation in the foot and ankle: a biomechanical study

Area of Science:

• Orthopedic Surgery
• Biomechanics
• Biomaterials

Background:

• Tendon transfers are a common surgical procedure in foot and ankle reconstruction.
• Various fixation methods exist, with bone anchors and interference screws being recent innovations.

Purpose of the Study:

• To biomechanically compare the fixation strength of interference screws versus bone anchors for split anterior tibial tendon transfers.
• To evaluate the influence of bone mineral density on fixation performance.

Main Methods:

• A biomechanical study using 15 fresh cadaver specimens.
• Split anterior tibial tendon transfer fixation at the cuboid using Corkscrew bone anchors and Bio-interference screws.
• Standardized X-rays for bone mineral density assessment and testing to maximal load to failure.

Main Results:

• Interference screws demonstrated a significantly higher ultimate load to failure (150 N) compared to bone anchors (103 N) (p = 0.003).
• No correlation was found between bone mineral density and the performance of either fixation technique.

Conclusions:

• Interference screws provide superior fixation strength for split anterior tibial tendon transfers compared to bone anchors.
• This finding suggests interference screws may offer enhanced stability in tendon-to-bone healing in foot and ankle surgery.