Injury differences: A sprain vs a strain; which tissue is injured and what is the common mechanism for a sprain?

• A. Sprain injures cartilage; mechanism compression
• B. Sprain injures tendon; mechanism direct impact
• C. Sprain injures ligament; mechanism inversion/twisting
• D. Sprain injures muscle; mechanism overload

Answer: (C)

Sprains involve injuries to ligaments, the bands that connect bones at a joint and keep the joint stable. A sprain means the ligament has been stretched or torn, usually from a twisting or turning force that pushes the joint beyond its normal range. The classic mechanism is an inversion twist of the ankle (often with some plantarflexion), where the ligaments on the outside of the joint are stressed or torn. This contrasts with strains, which affect muscle or tendon and result from overload or overstretching. Cartilage injuries come from compressive joint forces, not ligament tearing, and direct impact can injure bone or soft tissue rather than produce a typical sprain. So the best pairing is ligament injury from an inversion/twisting mechanism.