Sprains and strains are among the most common injuries
in sports. Sprains and strains generally cause swelling and pain,
and there may be bruises around the injured area.

• Sprain. A sprain is a stretching or tearing of ligaments. Ligaments are tough bands of fibrous tissue that connect one bone to another. They help to stabilize joints, preventing excessive movement. Sprains are frequently caused by rapid changes in direction or by a collision. Common locations for sprains are your ankles and knees.

• Strain. A strain is a stretching or tearing of muscle. This type of injury often occurs when muscles suddenly and powerfully contract - or when a muscle stretches unusually far. People commonly call muscle strains pulled muscles. Hamstring injuries are among the most common strains.

Treatment depends on the severity of the injury. Many times, self-care measures and over-the-counter pain medications are all that you'll need.

Signs and symptoms

Sprains and strains vary in severity. Signs and symptoms depend on the severity of the injury.

Sprains
Sprains can cause rapid swelling. Generally, the greater the pain and swelling, the more severe the injury.

• Mild. Your ligament stretches excessively or tears slightly. The area is somewhat painful, especially with movement. It's tender. There's not a lot of swelling. You can put weight on the joint.

• Moderate. The fibers in your ligament tear, but they don't rupture completely. The joint is tender, painful and difficult to move. The area is swollen and may be discolored from bleeding in the area. You may feel unsteady when you try to bear weight on your leg.

• Severe. One or more ligaments tear completely. The area is painful. You can't move your joint normally or put weight on it. If you try to walk, your leg feels as if it will give way. The joint becomes very swollen and also can be discolored. The injury may be difficult to distinguish from a fracture or dislocation, which requires medical care. You may need a brace to stabilize the joint or surgical repair in certain ligament injuries.

Strains
Depending on the severity of the strain, signs and symptoms may include:

• Mild. Pain and stiffness that occur with movement and may last a few days.

• Moderate. Partial muscle tears result in more extensive pain, swelling and bruising. The pain may last one to three weeks.

• Severe. The muscle is torn apart or ruptured. You may have significant bleeding, swelling and bruising around the muscle. Your muscle may not function at all, and you may need surgical repair if the muscle has torn away completely from the bone.

Causes

Sprains and strains occur commonly, and most result in minor injuries.

A muscle becomes strained or pulled — or may even tear — when it stretches unusually far or abruptly. This type of injury often occurs when muscles suddenly and powerfully contract. A muscle strain may occur when you slip on the ice, run, jump, throw, lift a heavy object or lift in an awkward position.

A sprain occurs when you overextend or tear a ligament while severely stressing a joint. You may sprain your knee or ankle when walking or exercising on an uneven surface. A sprain also may occur when you land awkwardly, either at the end of a jump or while pivoting during an athletic activity.