A sprain is a stretched or torn ligament. Ligaments are tissues that connect bones at a joint. Falling, twisting, or getting hit can all cause a sprain. Ankle and wrist sprains are common. Symptoms include pain, swelling, bruising, and being unable to move your joint. You might feel a pop or tear when the injury happens.

A strain is a stretched or torn muscle or tendon. Tendons are tissues that connect muscle to bone. Twisting or pulling these tissues can cause a strain. Strains can happen suddenly or develop over time. Back and hamstring muscle strains are common. Many people get strains playing sports. Symptoms include pain, muscle spasms, swelling, and trouble moving the muscle.

At first, treatment of both sprains and strains usually involves resting the injured area, icing it, wearing a bandage or device that compresses the area, and medicines. Later treatment might include exercise and physical therapy.

Strains can be acute or chronic. An acute strain is associated with a recent trauma or injury; it also can occur after improperly lifting heavy objects or overstressing the muscles. Chronic strains are usually the result of overuse: prolonged, repetitive movement of the muscles and tendons.

Doctors categorize or grade sprains.

Grade I Sprain

A grade I or mild sprain happens when you overstretch or slightly tear ligaments. If you have a mild sprain, usually you have:

• Minimal pain and swelling.
• Little or no loss of functional ability.
• Slight or no bruising.
• Little trouble putting weight on the affected joint.

Grade II Sprain

A grade II or moderate sprain happens when you tear a ligament further. When you have this type of sprain you have:

• Bruising.
• Moderate pain.
• Swelling.
• Difficulty putting weight on the joint.
• Some loss of function.

Grade III Sprain

A grade III sprain is usually severe and happens when you completely tear or rupture a ligament. If you have a grade III sprain you are unable to put your weight on the joint and have severe:

• Pain.
• Swelling.
• Bruising.

Sprains

Although sprains can occur in both the upper and lower parts of the body, the most common site is the ankle.

The ankle joint is supported by several lateral (outside) ligaments and medial (inside) ligaments. Most ankle sprains happen when the foot turns inward, called an inversion injury. You may be more likely to develop an ankle sprain when you:

• Run.
• Turn.
• Fall.
• Land on the ankle after a jump.

The knee is another common site for a sprain. You may be more likely to sprain your knee if you:

• Receive a blow to the knee.
• Fall.
• Suddenly twist the joint.

Another common location for a sprain is the wrist. This injury often occurs when a ligament near the base of the thumb (the ulnar collateral ligament of the metacarpophalangeal joint) is torn. You may be more likely to sprain your rest if you:

• Fall and land on an outstretched hand.
• Participate in skiing or other sports.

Strains

Two common sites for a strain are the back and the hamstring muscle (located in the back of the thigh). You may be more likely to develop a strain if you participate in contact sports such as:

• Soccer.
• Football.
• Hockey.
• Boxing.
• Wrestling.

You may be more likely to develop a strain in the hand or forearm if you participate in

• Gymnastics.
• Tennis.
• Rowing.
• Golf.
• Other sports that require extensive gripping.

You may be more likely to develop a strain in the elbow strains if you participate in:

• Racquet sports.
• Throwing.
• Contact sports.

Sprains

The causes of a sprain include a:

• Fall on an outstretched arm.
• Sudden twist of the joint when you land on the side of your foot.
• Blow to the body, for example sliding into a baseball base or hit in football.

When you force your joint out of its normal position you can stretch or tear the ligament supporting that joint.

Strains

A strain is caused by twisting or pulling a muscle or tendon. Strains can be acute or chronic. An acute strain is associated with a recent trauma or injury; it also can occur after improperly lifting heavy objects or overstressing the muscles. Chronic strains are usually the result of overuse: prolonged, repetitive movement of the muscles and tendons.

Sprains

The symptoms of a sprain include:

• Pain.
• Swelling.
• Bruising.
• Instability.
• Loss of the ability to move and use the joint (called functional ability).

The symptoms can vary and depend on the severity of the sprain. Sometimes you can feel a pop or tear when the injury happens.

Strains

In addition to pain, the symptoms of a strain can include:

• Limited motion.
• Muscle spasms.
• Possibly muscle weakness.
• Localized swelling.
• Cramping.
• Inflammation.
• Some loss of muscle function.

After a strain you typically have pain in the injured area and general weakness of the muscle when you try to move it. Severe strains that partially or completely tear the muscle or tendon are often very painful and disabling.

Doctors diagnose sprains and strains by:

• Asking questions about the injury.
• Examining the area of the inquiry.
• Ordering an x-ray to make sure you don’t have a fracture or broken bone.

Your doctor may order a magnetic resonance imaging or MRI help tell the differences between a partial injury and a complete tear in the ligament.

Treatments for sprains and strains are the same. To reduce swelling and pain in the first day or two, doctors usually say to:

• Rest the injured area. If the ankle or knee is hurt, your doctor may tell you to use crutches or a cane.
• Put ice on the injury for 20 minutes 4 to 8 times a day.
• Compress (squeeze) the injury using special bandages, casts, boots, or splints. Your doctor will tell you which one is best for you and how tight it should be.
• Put the injured ankle, knee, elbow, or wrist up on a pillow.
• Take medicines, such as aspirin or ibuprofen.

After treating pain and swelling, your doctor may tell you to exercise the injured area. This helps to prevent stiffness and increase strength. In addition, you may need physical therapy. Your doctor or physical therapist will tell you when you can start to do normal activities, including sports. If you begin too soon, you can injure the area again.

You can help prevent sprains and strains by:

• Avoiding exercise or playing sports when tired or in pain.
• Eating a well-balanced diet to keep muscles strong.
• Maintaining a healthy weight.
• Trying to avoid falling (for example, put sand or salt on icy spots on your front steps or sidewalks).
• Wearing shoes that fit well.
• Getting new shoes if the heel wears down on one side.
• Exercising every day.
• Staying in proper physical condition to play a sport.
• Warming up and stretching before playing a sport.
• Wearing protective equipment when playing.
• Running on flat surfaces.

The goal is to get you back to your normal everyday activities, including sports if possible. You should work closely with your doctor or physical therapist to make sure you are ready. It is important that you have the following before returning to normal activity or sports:

• Normal motion.
• Flexibility.
• Strength.

The amount of time you need to fully heal after a sprain or strain depends on the person and the type of injury.