Knee Sprain

A knee sprain is stretching or tearing of the ligaments that support the knee. Ligaments are strong bands of tissue that connect bones to each other.

Knee sprains may be caused by:

• Blow to the front of the knee while the knee is bent and the foot is firmly planted on the ground
• Blow to the outer or inner side of the knee
• Forced twisting of the knee
• Landing awkwardly after jumping
• Shifting your weight while running or skiing
• Stopping suddenly while running

These factors increase your chance of developing a knee sprain. Tell your doctor if you have any of these risk factors:

• Inadequate flexibility and strength in muscles and ligaments
• Loose joints
• Playing sports
• Poor balance
• Poor coordination

Symptoms include:

• Decreased range of motion in the knee
• Inability to stand on the affected leg
• Pain in the knee
• Swelling within the knee
• Swelling, redness, warmth, or bruising around the knee
• Tenderness where the injured ligament attaches to a bone in the knee

Your doctor will ask about your symptoms and how the injury occurred. The knee will be checked to see how stable the joint is and how severe the pain is. Tests may include:

• MRI scan —a test that uses a magnetic field to make pictures of structures to assess if a ligament has torn completely (less commonly used)
• X-rays —a test that uses radiation to take pictures of structures inside the body, especially bone (to assess if any bones are broken)

Treatment includes:

• Compression—Wrap your knee in an elastic bandage (eg, Ace bandage). This will limit swelling and provide some support for your knee. Be careful not to wrap the bandage too tight.
• Medication—Ask your doctor which pain medication you should use. Common ones include:
  • Acetaminophen (Tylenol)
  • Aspirin
  • Ibuprofen (Motrin, Advil)
  • Naproxen (Aleve, Naprosyn)
• Brace—You may need to wear a brace. Your doctor may also recommend that you wear a brace when you return to sports. Although, the American Academy of Pediatrics recommends that children do not use braces.
• Elevation—Keep the injured knee raised above the level of your heart. Do this as much as possible for 24 hours or so. This will help drain fluid and reduce swelling. For severe sprains, you may need to do this for a couple of days.
• Ice—Apply ice or a cold pack to the knee for 15-20 minutes, four times a day for two days. This helps reduce pain and swelling. Wrap the ice or cold pack in a towel. Do not apply ice directly to your skin.
• Leg cast—If you have a severe sprain, you may need to wear a short leg cast for 2-3 weeks.
• Rehabilitation exercises—Ask your doctor about exercises to restore flexibility, range of motion, and strength.
• Rest—Avoid putting any pressure on your knee by not walking on that leg.
• Surgery—This may be needed if a ligament is torn completely.

To reduce your risk of spraining a knee:

• Do exercises that strengthen the leg muscles.
• Warm up and stretch before exercise. Cool down and stretch after exercise.
• Ask your doctor if you should use a brace.
• Learn the proper technique for sports and exercise. This will decrease stress on all your muscles, ligaments, and tendons, including those around your knee. Also, wear the proper equipment.
• Take a break from sports and exercise when you feel tired.