Influence of bone staple design on interfragmentary compression

Area of Science:

• Orthopedic biomechanics
• Surgical fixation devices

Background:

• Staple fixation is typically considered static but can be engineered for dynamic compression.
• Understanding staple design is crucial for optimizing interfragmentary compression in bone healing.

Purpose of the Study:

• To analyze staple design features that influence interfragmentary compression.
• To evaluate a manipulative technique for enhancing compression during bone fixation.

Main Methods:

• Measured compressive forces of 13 bone fixation staple designs using pressure-sensitive film.
• Tested staple designs in both a wood-block model and cadaveric bone.
• Analyzed the effects of outward leg splaying, internal/external beveling, and leg tapering.

Main Results:

• Staples with outward-splayed legs generated significantly higher compressive forces than standard designs.
• Internal beveling of staple leg tips increased compression, while external beveling caused distraction.
• Tapered legs produced compression but led to splitting in the wood-block model.

Conclusions:

• Outward splaying of staple legs is an effective and simple method to increase compression.
• Optimized staple design can enhance dynamic compression for improved bone fixation.
• Design modifications offer a versatile approach to achieving desired compression in orthopedic surgery.