What is a sprain?

A sprain is a stretched or torn ligament. Ligaments connect one bone to another bone at a joint and help keep the bones from moving out of place.

The most common site of sprains is the ankle. An ankle sprain can happen when you fall, when you suddenly twist your ankle too far, or when you force the joint out of its normal position (for example, when you land awkwardly on your foot after jumping). Most ankle sprains happen during sports activities or when walking or running on an uneven surface.

The signs of an ankle sprain can include:

  • pain or tenderness
  • swelling
  • bruising
  • coldness or numbness in the foot
  • inability to walk or bear weight on the joint
  • stiffness

The severity of an ankle sprain depends on how badly the ligaments are stretched or torn. If the sprain is mild, there may not be much pain or swelling, and the ligaments may only be stretched. If the sprain is severe, one of more ligaments may be torn, and the join may be severely swollen. A severe sprain can also be extremely painful.