CausesBy Mayo Clinic staff
A sprain occurs when you overextend or tear a ligament while severely stressing a joint. Sprains often occur in the following circumstances:
- Ankle. Walking or exercising on an uneven surface
- Knee. Pivoting during an athletic activity
- Wrist. Landing on an outstretched hand during a fall
- Thumb. Skiing or playing racquet sports, such as tennis
There are two types of strains: acute and chronic. An acute strain occurs when a muscle becomes strained or pulled — or may even tear — when it stretches unusually far or abruptly. Acute strains often occur in the following ways:
- Slipping on ice
- Running, jumping or throwing
- Lifting a heavy object or lifting in an awkward position
A chronic strain results from prolonged, repetitive movement of a muscle. This may occur on the job or during sports, such as:
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