What is collateral ligament injury of the knee?

A collateral ligament injury is a knee sprain caused by a blow to the knee or by a twisting of the knee.

Ligaments are fibrous tissues or bands that connect bone to bone and prevent joints from dislocating. They don't stretch and therefore have a limited range of motion. There are collateral ligaments on both sides of the knee. They connect the upper leg bone with one of the lower leg bones. The injury can occur on either side of the knee.

A sprain is the wrenching, twisting, or stretching of a joint and tearing of its ligaments. Sprains vary from minor tears in a few fibers of ligament to complete tears of entire ligaments and loss of use of the joint.

How does it occur?

A collateral ligament injury most often occurs in contact sports as a result of a blow to the knee from the side, pushing the knee inward or outward. The ligament most often torn is the one on the inside (medial) side of the knee (where your knees touch).

What are the symptoms?

The symptoms of a mild sprain include:

• minimal pain with movement

• tenderness

• swelling at site of injury

• no loss of use of the joint.

The symptoms of a moderate sprain include:

• increased pain with movement so that you don't want to use the knee

• some loss of use of the joint

• swelling.

The symptoms of a severe sprain include:

• severe pain

• noticeable loss of use of the joint

• immediate swelling.

How it it diagnosed?

To diagnose collateral ligament injury, the doctor will review your symptoms and determine how the injury happened. He or she will examine the knee to determine the extent of your injury and the degree (grade) of your strain.

The doctor may order x-rays of the knee to rule out fracture and disease. Stress films may be needed to determine the stability of your knee joint.

Also, the doctor may draw fluid from the knee and send it to a lab for analysis.

How is it treated?

The treatment for collateral ligament injury in general consists of rest, ice, compression, and elevation (RICE). Rest your knee and keep your leg elevated. Use an ice pack on your knee to keep the swelling down. Ice your knee for 20 to 30 minutes, three to four times a day for a week, then once a day until symptoms are gone. A compression bandage wrapped around your knee will help give your knee support.

Your doctor may recommend or prescribe an anti-inflammatory medicine and give you exercises for your knee. Other treatment depends on how badly you sprained your knee.

Grade I sprains:

For acute pain, the doctor will ask you to eliminate all kneeling, squatting, and stair-climbing. In addition, he or she may:

• possibly put you on crutches

• recommend knee supports when appropriate.

Grade II sprains:

The doctor will give you crutches and a knee brace to use until the pain subsides.

Grade III sprains:

The doctor will immobilize your knee in a splint for a few days until the pain subsides. You also will be on crutches. Range-of-motion exercises will be begun usually within a few weeks of the injury.

How long will the effects last?

The time it takes your knee to heal depends on the grade of the sprain and your general health. You may notice the effects of the sprain for several weeks.

How can I take care of myself?

• Perform strengthening and rehab exercises for your injured knee.

• If pain occurs, contact your doctor and decrease your activity to a pain-free level.

• Return to your prior level of activity gradually.

• Talk to your doctor about a knee brace to wear during sports.

• Seek early treatment if an injury occurs or recurs, and remember RICE.

How can I help prevent collateral ligament injury of the knee?

To help to prevent a collateral ligament injury, follow these measures:

• Stay in good shape and think about safety.

• When you exercise, wear properly fitting shoes, appropriate for the kind of exercise you're doing.

• Perform gentle stretching exercises before and especially after exercising.