Sudden stretching or tearing of the supporting ligaments within the knee joint is referred to as a Knee Sprain. It is a common type of injury that affects people irrespective of age or gender. The knee joint is supported and protected by four ligaments. The center of the joint has the two cruciate ligaments – Anterior Cruciate Ligament (ACL) and the Posterior Cruciate Ligament (PCL). The sides of the joint are bound by the collateral ligaments- Medial Collateral Ligament (MCL) and the Lateral Collateral Ligament (LCL). Any of these ligaments may get stretched beyond their normal capacity causing a tear or sprain.


  • Sudden twist of the knee while walking, running, playing or exercising
  • Over straightening or hyperextension of the knee
  • Stopping suddenly while moving or playing
  • A direct blow to the knee may cause ligament damage
  • Vehicular accidents (when the knee is smashed against the dashboard)
  • Falling while the knee is bent
  • Overpronation may increase the risk of a knee sprain
  • Not warming up before a game or exercise
  • Past knee injuries may cause weakening of the ligaments and result in a sprain
  • Sudden enhancement in the intensity of workout


  • Instability – the knee seems to give away while standing or moving
  • Pain – it may vary from a dull throb to being severe depending on the extent of ligament damage. The pain starts immediately or within a few hours of injury
  • Inability to bear bodyweight
  • Discoloration, swelling and tenderness may be observed
  • A popping sound is heard or felt inside the joint at the time of injury Limited range of motion remains


  • The time and mode of injury besides the existing symptoms may be investigated
  • The injured, as well as non-injured knees, may be examined for comparison
  • Range of motion may be tested
  • X-ray imaging may be suggested to check for fractures, grade of ligament tear and detachment of bone pieces along with ligament
  • MRI scan may be required


  • RICE therapy – this involves resting the knee, applying ice packs at regular intervals, using soft compression and keeping it elevated at chest level
  • Medication – pain killers and anti-inflammatory drugs may be prescribed
  • Use of knee brace may be helpful in supporting the injured joint
  • Exercises – specific rehabilitation exercise plan may be prescribed to strengthen the injured knee and to prevent any more injuries
  • Arthroscopic surgery may be done to reconstruct damaged ligament using own tissue or form a donor
  • Any activity that aggravates the symptoms should be avoided