Restoring Function. Embracing Life.
ACL Knee Specialist in Singapore
Dr Bryan Wang
Consultant Orthopaedic Surgeon
Trusted Orthopaedic Surgeon | Fellowship-trained in Canada | With over 15-years of experience
What is Knee Ligament Injury? What is ACL or PCL?
The knee is a hinge joint held together by four ligaments. There is a ligament on each side of the knee (the collateral ligaments) and two ligaments deep inside the knee. The two ligaments inside the knee that cross each other are called the anterior cruciate ligament (ACL) and the posterior cruciate ligament (PCL). Both ligaments attach on one side to the end of the thigh bone (femur) and on the other to the top of the shinbone (tibia).
A knee ligament injury is damage or tearing of one of the ligaments in the knee joint. Ligaments are tough bands of tissue that connect bones to each other, providing stability and support to the joint. The knee joint contains several ligaments, and injuries can occur to any of them, but the most common ones affected are the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), and lateral collateral ligament (LCL).
Anterior Cruciate Ligament (ACL) Injuries
During activity, the ACL controls how far forward the tibia can "slide" relative to the femur: it essentially acts to prevent too much forward movement. While some degree of motion or sliding is normal and is required for knee function, too much motion may damage other structures in the knee which can lead to long term problems in some patients.
The ACL can be injured or torn in a number of different ways. The most common mechanism is that of a sudden pivoting or cutting manoeuvre during sporting activity, which is commonly seen in football, basketball and soccer.
Bouncing Back: Navigating The Challenges Of ACL Injuries
Types of ACL injuries
Gradings of the ACL injuries and tears are a quick way to describe the extent of your injury. ACL injury grades range from one (the least severe) to three (the most severe):
Grade one: The injury stretched your ACL enough to damage it, but it’s still in one piece and holding your knee bones together.
Grade two: The injury stretched your ACL so much that it was partially torn and loosened.
Grade three: A complete tear — your ACL is in two pieces.
What are the ACL injury symptoms?
Signs and symptoms of an ACL injury usually include:
A ‘pop’ sound in the knee at the time of injury
Swelling of the knee
Inability to bear weight on leg (though some have little or no pain)
A feeling of instability or ‘giving-way’
Losing your range of motion
How to Diagnose ACL injury?
Clinical assessment will include taking a detailed history and a thorough examination of your knee. Further imaging tests like X-rays, MRI scans and ultrasound scans may occasionally be required.
Posterior Cruciate Ligament (PCL) Injuries
The PCL is located deep within the knee joint and connects the femur (thighbone) to the tibia (shinbone). Its primary function is to prevent the tibia from moving too far backward in relation to the femur.
PCL injuries typically occur due to direct impact to the front of the knee while it's bent, such as in a car accident when the knee strikes the dashboard. Sports injuries or falls onto the knee can also cause PCL injuries. These injuries can range from mild sprains, involving partial tearing of the ligament, to severe tears or ruptures, involving complete tearing of the ligament.
What are the PCL injury symptoms?
Signs and symptoms of an ACL injury usually include:
Pain, especially at the back of the knee
Swelling
Instability or a feeling of the knee giving out
Difficulty bearing weight on the affected leg
Limited range of motion
Difficulty walking or participating in activities that require knee movement
How to Diagnose PCL injury?
Clinical assessment will include taking a detailed history and a thorough examination of your knee. Further imaging tests like X-rays, MRI scans and ultrasound scans may occasionally be required.
Knee Ligament Injuries Treatment
What are my Treatment options?
If you have any of the symptoms above, it is advisable to see an orthopaedic specialist for further assessment. The appropriate treatment is decided after assessment and a collaborative discussion based on your needs. They can be broadly divided into conservative (non-surgical) and surgical options.
Conservative Treatment
Non-surgical treatment is most appropriate for Grade 1 injuries. These may include a combination or all of the following measures:
Knee brace
immobilisation may be needed to allow the ACL to heal
Cold packs
to reduce swelling
Physiotherapy
strengthening of the quadriceps muscles can help with stability
Gradual progression
back to regular activities and sports
Surgical Treatment
Surgical treatment may be recommended for individuals with a complete ACL tear, especially if you are active and wish to return to sports which require pivoting movements (ie soccer, basketball).
Surgery is also beneficial if your knee remains unstable despite a period of non-surgical treatment, with frequent ‘giving-way’ or buckling during your daily activities.
Persistent buckling of the knee may lead to a higher risk of developing osteoarthritis as well as other associated injuries (meniscus, cartilage).
During an ACL reconstruction, the damaged ligament is removed and replaced with a segment of tendon — tissue similar to a ligament that connects muscle to bone. This replacement tissue is called a graft. The graft may either be from your own body (autograft) or from a deceased donor (allograft).
After surgery, you will require an intensive course of rehabilitative therapy. Successful ACL reconstruction paired with rigorous rehabilitation can usually restore stability and function to your knee.
In general, it takes as long as a year or more before athletes can safely return to play. The medical team will perform tests to gauge your knee's stability, strength, function and readiness to return to sports activities at various intervals during your rehabilitation. It is important to ensure that strength, stability and movement patterns are optimised before you return to an activity which requires pivoting movements.
