Which term describes twisting about an axis in tissue loading?

Which term describes twisting about an axis in tissue loading?

• A. Torsion
• B. Tension
• C. Compression
• D. Shearing

Answer: (A)

The key idea is twisting around an axis, which is what torsion describes. When a structure is twisted along its length, one end rotates relative to the other around the long axis, creating rotational or angular deformation. That’s different from tension, which is a pull that lengthens the tissue; from compression, which pushes tissue together and shortens it; or from shear, which makes adjacent layers slide past one another without actually rotating the whole structure about an axis. So twisting around the axis of the tissue is torsion, which is why that term is the best description for this loading scenario.