Knee ligament injuries
The knee is the largest joint in the body and one of the most complex. It is also vital to movement.
Ligaments are structures that hold the joints together and allow the big muscles to move them in different directions. The knee ligaments connect the thigh bone to the lower leg bones. Knee ligament sprains or tears are common sports injuries.
In the 1980's, injuring more than one ligament would certainly have put an end to a sporting career. This is not the case now. Today we have advanced both in rehabilitation and surgical procedures to deal with these ligament injuries and it is often possible to return to full competitive sports after multiple ligament injury.
Normal Right knee anatomy, front view
Three bones meet to form your knee joint: your thigh bone (femur), shin bone (tibia), and kneecap (patella). Your kneecap sits in front of the joint to provide some protection.
Bones are connected to other bones by ligaments. There are four main ligaments in your knee. They act like strong ropes to hold the bones together and keep your knee stable.
These are found on either side of your knee. The medial collateral ligament (MCL) is on the inside and the lateral collateral ligament (LCL) is on the outside. They control the sideways motion of your knee and brace it against unusual movement.
Anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) are found inside your knee joint. They cross each other to form an "X" with the anterior cruciate ligament in front and the posterior cruciate ligament behind. The cruciate ligaments control the backwards and forwards motion of your knee.
What causes the knee ligaments to get injured?
Because the knee joint relies just on these ligaments and the surrounding muscles for stability, it is easily injured. Any direct contact to the knee or hard muscle contraction — such as changing direction rapidly while running — can injure a knee ligament.
Injured ligaments are considered "sprains" and are graded on a scale.
Grade 1 Sprains: The ligament is mildly damaged in a Grade 1 Sprain. It has been slightly stretched, but is still able to stabilise the knee joint.
Grade 2 Sprains: A Grade 2 Sprain stretches the ligament to the point where it becomes loose. This is often referred to as a partial tear of the ligament.
Grade 3 Sprains: This type of sprain is most commonly referred to as a complete tear of the ligament. The ligament has been split into two pieces, and the knee joint is unstable.
It is possible to injure two or more ligaments at the same time. These multiple injuries can have serious complications. They can disrupt blood supply to the leg. They can also affect the nerves that supply the muscles of the leg.
Right knee Anterior Cruciate Ligament tear (left side image) & Medial Collateral Ligament tear (right image)
The MCL is injured more often than the LCL. Due to the more complex anatomy of the outside of the knee, if you injure your LCL, you usually injure other structures in the joint, as well.
What are the Symptoms of Ligament Injuries?
This depends on which ligament is injured. The most common ones (MCL & ACL) could be injured on their own or both together.
- Pain and swelling of the whole knee joint with ACL or PCL injury
- Swelling can be just around the MCL or LCL ligaments if they are involved.
- Localised pain and tenderness around the MCL or LCL.
- Pain and or instability in weightbearing & with turning / twisting movements.
What are the Treatments available to treat Ligament Injuries?
You will need a thorough examination by an experienced clinician. Depending on the injury, you may need a specialist physiotherapist and a surgical opinion to help decide on the best treatment.
Simple ligament tears
- Follow the initial injury management steps including "PRICE" protocol.
- Protection - avoid putting strain on your knee joint, sometimes it helps to support the knee with a brace.
- Rest - avoid painful or repetitive activities
- Ice - use an ice pack or a bag of frozen peas wrapped in a damp towel for a maximum of 15 minutes. This can be repeated every 3 hours. Avoid placing ice directly on your skin.
- Compression bandage - This should go from your ankle up to the top of your thigh.
- Elevation - Try to elevate your leg higher than your chest level in lying for 20-30 minutes 3-4 times a day.
- If the ACL is injured, the treatment varies vastly between individuals and may need surgery depending on your age and activity. Otherwise physiotherapy might be the best treatment.
- For most ligament injuries gentle exercises must be started to regain movement within a few days.
- If the MCL (the ligament on inside of the knee) is injured this may sometimes need a period of immobilisation with a brace before starting exercises. This must be done with the advice of a specialist physiotherapist.
Multiple ligament Injuries
- Recent evidence points out that combined ligament tears may need an early surgical opinion.
- In the past, a multiple ligament injury prevented people from returning to sports activities. Today, it is possible to return to high level sports, although there is no certainty of it.