Lateral Knee Pain (Pain on the Side of the Knee)

Lateral Knee Pain (Pain on the Outer Side of the Knee)

Lateral knee pain is discomfort occurring on the outer part of the knee. In most cases, it affects young individuals due to direct trauma to the knee. Generally, lateral knee pain accompanied by swelling around the outer knee is often caused by iliotibial band syndrome, meniscus tears, or mild to moderate LCL and MCL injuries.

• The pain may develop gradually over time or occur suddenly after an injury.
• It is often accompanied by swelling, especially if a ligament is torn.
• It may limit knee movement and mobility.

Causes of Lateral Knee Pain

1. Iliotibial Band Syndrome (ITBS)

ITBS is one of the most common causes of outer knee pain, especially among athletes and runners. This condition usually results from overuse of the knee joint, muscle tightness or weakness, flat feet, or a sudden increase in activity.

Symptoms: Pain on the outer knee, worsened by running (especially when the heel strikes the ground), cycling, squatting, climbing stairs, or walking.

2. Lateral Collateral Ligament (LCL) Injury

LCL injury occurs when a direct impact to the inner knee causes damage to the ligament on the outer knee. Pain and instability in the knee may indicate an LCL or ACL injury.

Symptoms: Swelling on the outer knee due to fluid accumulation, pain on the outer side of the knee, bruising, instability, and a sensation of the knee “giving out.”

3. Lateral Meniscus Tear

A lateral meniscus tear can also cause pain on the outer knee. This injury commonly results from sudden knee twisting, especially when the knee is bent, or from gradual wear and tear.

Symptoms: Lateral knee pain, knee locking (difficulty moving the knee), instability, and trouble fully straightening the knee.

4. Hamstring Tendinopathy

Tendinopathy of the biceps femoris muscle can cause pain in the back outer side of the knee. It is often caused by repetitive knee strain, excessive jumping, or kicking.

Symptoms: Tenderness to touch, pain in the outer knee (especially at the back), worsened by knee bending.

5. Nerve Issues in the Knee

Compression of the peroneal nerve, which runs along the outer lower leg, can also cause lateral knee pain. This nerve originates from the sciatic nerve and runs down the outer shin to the foot. Peroneal nerve injury often occurs due to direct trauma to the side of the knee, where the nerve is close to the skin.

Symptoms: Pain accompanied by tingling or numbness in the affected area.

Treatment for Lateral Knee Pain

The best treatment depends on the underlying cause of the pain. Most treatment plans include a combination of:

• Physical therapy and rehabilitation exercises to strengthen and stabilize the knee.
• Rest and activity modification to avoid movements that aggravate the pain.
• Pain management options, including ice therapy, anti-inflammatory medications, and knee braces.
• Injections or surgery, in severe cases where conservative treatments do not provide relief.

Seeking early diagnosis and proper treatment can prevent complications and improve knee function.