Knee Ligament Injuries

Ligaments connect one bone in a joint to another to provide stability. A sprain is where one or more ligaments are overstretched by twisting or pulling. This can cause mild stretching  (grade 1 sprain), partial tear (grade 2 sprain) or complete tear (grade 3 sprain).

Knee ligament injuries are very common and are often sports or trauma related. They are common in footballers, gymnasts, skiers and other sports.

There are 4 ligaments that stabilise the knee joint. The two ligaments that sit outside the joint are the medial collateral ligament (MCL) on the inner aspect of the knee and the lateral collateral ligament (LCL) on the outer aspect of the knee. They limit the side to side movement of the knee. The MCL is more commonly sprained or torn. This can happen when you twist on a straight knee at the same time as the knee being knocked sideways e.g. skiing or a rugby tackle.

There are 2 ligaments within the knee joint which stabilise the knee in a forward and backward direction. They are called the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL). The ACL is more commonly injured due to twisting on the knee whilst the foot is planted or twisting the knee during a landing. ACL tears are usually accompanied by significant swelling of the knee within a few hours. The PCL can be injured by falling onto a bent knee or the knees hitting the dashboard during a car accident.


Can include:

  • pain, can be sudden & severe
  • A loud ‘pop’ or ‘snap’ during the injury
  • Pain on weight bearing
  • Gradual swelling +/- bruising over several days
  • Sudden large swelling within a few hours may indicate an ACL tear
  • Instability – your knee may give way or feel like it might, due to the reduction in the stabilising action of the ligaments


– Diagnosis can usually be made by a combination of listening to the history of injury, symptoms and examination by your GP or health care practitioner.

– Special tests are carried out by the GP or clinician to assess the ligaments, such as the anterior draw test for the ACL.

– Investigations may be required depending on symptoms and clinical findings.

X-ray may be carried out to exclude bony injury if appropriate.

MRI will show more detailed imaging inside the knee if required.


  • ​Regular exercise – Please click here to read more about the benefits of regular exercise
  • Pain relief
  • Physiotherapy – see your GP to discuss physiotherapy referral if symptoms are failing to improve after 6 weeks of self management and exercises.
  • However seek  advice and physiotherapy referral sooner if there is significant swelling and instability (giving way) of the knee following a trauma
  • Surgery may be required if conservative management fails to improve symptoms or the knee continues to be unstable.

Early-Stage Management:

Please click the arrow below to view suitable exercises for early stage management of ligament injuries.


Mid-Stage Management:

Please click the arrow below to view suitable exercises for mid stage management of ligament injuries.

USEFUL LINKS – further information about ligament injuries of the knee – includes advice regarding surgery for ligament tears. – information about ligament injuries

https://www.nhsinform.Scot/injuries/muscle-bone-and-joint-injuries-problems – general advice about the management of knee pain