ACL Specialist In Singapore

doctor img
Dr Kau Chung Yuan (许医生)


MRCS (Ireland)

MMed (Ortho)

FRCSEd (Ortho)


What Is The Anterior Cruciate Ligament (ACL)?

The Anterior Cruciate Ligament (ACL) is a tissue that connects the thigh bone to the shinbone and controls the front and back motion of the knee. It provides rotational control and stability by limiting forward movement of the thigh bone on the shin bone. Without an intact ACL, the knee may feel loose and wobbly.

An ACL tear is a common knee injury that occurs during sports with sudden twisting motions and changes in direction. When the ACL tears, the anterior cruciate ligament sprains or splits from the bone attachments.

What Are ACL Tear Symptoms?

When you tear your ACL, you may hear a popping sound. Other symptoms may follow, such as:

  • Swelling in the knee
  • Pain and tenderness at the joint
  • Loss of full range of motion
  • A feeling of instability, especially when weight is put on the joint

What Causes An ACL Tear?

It is more common for ACL tears to occur during sports activities when the knee is vulnerable to injury. Certain movements can cause an ACL tear including:

  • Sudden change in direction
  • Suddenly stopping
  • Landing from a jump
  • Getting into an impactful collision directly on the knee

Playing sports such as football, basketball and tennis have a higher risk of tearing the ACL.

What Are The Risk Factors Of An ACL Tear?

Several risk factors can increase the likelihood of sustaining an ACL tear. Understanding these factors can help people take preventive measures and be more aware of their susceptibility to such injuries. The primary risk factors for an ACL tear include:


Women are more likely to suffer ACL tears than men. This increased risk is attributed to several anatomical and hormonal differences, including the following:

  • Wider pelvis leading to greater knee valgus (inward collapse).
  • Differences in muscle strength and recruitment patterns.
  • Hormonal fluctuations that may affect ligament laxity.
Sports Participation

Engaging in sports that involve high-intensity movements such as jumping, pivoting, and sudden changes in direction can significantly increase the risk of ACL tears. High-risk sports include:

  • Soccer
  • Basketball
  • American football
  • Skiing
  • Rugby
Previous ACL Injury

People who have previously sustained an ACL injury are at a higher risk of re-injury. This increased risk can be due to factors such as inadequate rehabilitation, persistent muscle weakness, or altered movement patterns.

Genetic Factors

Genetics may play a role in predisposing people to ACL injuries. Some people may have inherited anatomical characteristics or ligament properties that make them more prone to ACL tears.

Poor Conditioning

Lack of proper conditioning and muscle strength can increase the risk of ACL injuries. Weak muscles around the knee can lead to instability and improper movement patterns, increasing the likelihood of ligament tears.

Improper Technique

Using incorrect techniques during physical activities can place undue stress on the ACL. For instance, landing from a jump with knees caving inward or making abrupt changes in direction without proper body alignment can elevate the risk of injury.

Environmental Factors

Certain environmental conditions can also contribute to ACL injuries. Slippery or uneven playing surfaces, inappropriate footwear, and inadequate sports equipment can increase the likelihood of sustaining an ACL tear.

How Do You Prevent An ACL Tear?

Even though ACL tears are common, they can be prevented through strength training and learning good exercise techniques. Some examples include:

  • Strengthening the core muscles
  • Practising proper landing techniques
  • Strengthening leg muscles
  • Good warm-up practices

What Should You Do If You Think You Have Torn Your ACL?

If you suspect you have torn your ACL, stop all physical activities and keep weight off your leg by sitting down. Make an appointment immediately with your orthopaedic specialist. Keep your leg raised above chest level until then, and ice the area if you notice swelling. Refrain from putting pressure on your knees and take over-the-counter pain medication to manage the discomfort.


Are Your Symptoms Affecting Your Quality Of Life?

Consult our MOH-accredited orthopaedic specialist for an accurate diagnosis & personalised treatment plan today.

How Is An ACL Tear Diagnosed?

An ACL tear is typically diagnosed through a combination of physical examination, patient history, and imaging tests. Initially, your orthopaedic specialist will assess the knee’s stability, swelling, and range of motion. They may perform specific maneuvers, such as the Lachman test, to check the integrity of the ACL.

Accessing how the injury occurred and the symptoms experienced are also crucial for a preliminary diagnosis. To confirm the extent of the tear and to rule out damage to other knee structures, magnetic resonance imaging (MRI) scans are often utilized. In some cases, X-rays might be ordered to exclude bone fractures. This comprehensive approach ensures an accurate diagnosis, which is essential for determining the most effective treatment plan.

What Are The Grades Of An ACL Injury?

An ACL injury is classified into a three-class grading system that signifies the severity of the injury. Grade 1 injuries are the least severe, while Grade 3 injuries are the most severe. Depending on the grade, treatment for the ACL tear may vary.

  • Grade 1
    The ligament is slightly stretched but not torn and can still maintain the knee’s stability.
  • Grade 2
    The ligament is partially torn and loose.
  • Grade 3
    The ACL is completely torn and split into two, making the knee unstable.

Complications of an ACL Tear

An ACL tear is a serious injury that can lead to a variety of complications if not properly managed. These complications can affect both short-term recovery and long-term knee function. Understanding the potential complications associated with an ACL tear can help people seek appropriate treatment and adhere to recommended rehabilitation protocols.

Immediate Complications

  • Knee Instability: A torn ACL can result in significant knee instability. Without the stabilising function of the ACL, the knee may give way during physical activities, increasing the risk of further injury.
  • Joint Effusion: ACL tears often cause joint effusion, or swelling within the knee joint. This swelling can cause pain, reduce the range of motion, and make it difficult to bear weight on the affected leg.
  • Pain and Limited Mobility: Immediately following an ACL tear, people often experience severe pain and limited mobility. This can affect daily activities and overall quality of life.
Long-Term Complications

  • Chronic Knee Instability: If an ACL tear is not adequately treated, chronic knee instability can develop, impairing the ability to participate in sports and other physical activities and potentially affecting routine movements.
  • Osteoarthritis: One of the most significant long-term complications of an ACL tear is the development of osteoarthritis in the knee joint. The altered mechanics and increased instability can lead to abnormal wear and tear on the cartilage, increasing the risk of osteoarthritis over time.
  • Meniscal Injuries: ACL tears are often associated with concurrent injuries to the meniscus, the cartilage that cushions the knee joint. Untreated or improperly managed ACL injuries can exacerbate meniscal damage, leading to further joint degeneration and pain.
  • Muscle Weakness and Atrophy: Prolonged periods of inactivity or insufficient rehabilitation can result in muscle weakness and atrophy, particularly in the quadriceps and hamstrings. This muscle imbalance can contribute to knee instability and increase the risk of re-injury.
  • Reduced Athletic Performance: For athletes, an ACL tear and its complications can significantly reduce athletic performance. Even with proper treatment and rehabilitation, some people may never regain their pre-injury performance level.

What Happens If A Torn ACL Goes Untreated?

Not all ACL injuries require surgical treatment. Grade 1 ACL tears are usually treated with physical therapy and immobilisation.

However, if a torn ACL goes untreated, it may lead to:

  • Bleeding and blood clots that can worsen the condition
  • Ongoing severe pain
  • Weakness in the knees
  • Reduced mobility

It is important to make an appointment with an orthopaedic specialist to understand the best treatment plan for your ACL injury.

ACL Treatment Options

Non-Surgical Treatments for ACL Injuries

Physical Therapy

Physical therapy focuses on strengthening the muscles around the knee to improve stability and function. It often includes exercises to enhance flexibility, strength, and proprioception.


Knee braces can provide additional support and stability, helping to protect the knee during the healing process and during physical activities.


Non-steroidal anti-inflammatory drugs (NSAIDs) can help reduce pain and inflammation associated with ACL injuries and aid in the overall recovery process.

Surgical Treatment for ACL Injuries

When non-surgical treatments are insufficient, surgical intervention may be necessary to restore knee stability and function. The choice of surgical technique depends on various factors, including the patient’s activity level, age, and the severity of the injury.

Knee Arthroscopy

Knee arthroscopy is a minimally invasive surgical procedure used to diagnose and treat various knee joint issues, including ACL tears. This procedure involves the following steps:

Procedure for Knee Arthroscopy
  • Preparation and Anaesthesia: The patient is positioned on the operating table, and either general or regional anaesthesia is administered to ensure comfort during the procedure.
  • Incisions and Insertion of Arthroscope: Small incisions, typically less than a centimetre, are made around the knee. An arthroscope, a small camera device, is inserted through one of the incisions, providing a clear, magnified view of the inside of the knee joint on a monitor.
  • Assessment and Repair: Additional small incisions are made to insert specialised surgical instruments. The surgeon examines the knee joint, identifies the damaged ACL, and repairs or removes the damaged tissue using these instruments. This minimally invasive technique allows for precise repairs with minimal disruption to surrounding tissues.
  • Closure and Dressing: Once the repair is complete, the instruments and arthroscopy are removed, and the small incisions are closed with sutures or sterile strips. The knee is then dressed with a sterile bandage.

Dr. Kau Chung Yuan

MBBS (S’pore)

MRCS (Ireland)

MMed (Ortho)

FRCSEd (Ortho)

Dr Kau (许医生) is a Fellowship trained Orthopaedic Surgeon with a subspecialty interest in Hip and Knee surgery and has been in practice for more than 15 years.

He is experienced in trauma and fracture management, sports injuries, and joint replacement surgery.

  • Fellow of the Royal College of Surgeons Edinburgh, Orthopaedics (FRCS, Edin) 2014
  • Master of Medicine (Orthopaedics), Singapore (MMed) 2013
  • Member of the Royal College of Surgeons Ireland (MRCS, Ire) 2009
  • Bachelor of Medicine and Surgery (MBBS, Singapore) 2004

What Is The Cost Of ACL Surgery In Singapore?

According to MOH’s fee guideline, knee arthroscopy ACL surgery costs an average of $30,000 at a private hospital. This fee is calculated before deducting your personal insurance plans (Integrated Shield Plans, Medishield Life) and MediSave payouts. The maximum MediSave payout you can obtain for a knee arthroscopy is $3,950.

Dr Kau (许医生) is on the panel for most major local insurers. Talk to our team and your insurance agent to understand the out-of-pocket fees required for a knee arthroscopy.

Partnered Programs & Insurance Plans

For Singaporeans, Singapore Permanent Residents and Foreigners.
Please speak to our friendly clinic staff about using your insurance plans.

Patient Feedback

Ethan Chan
Dr. Kau is an exemplary doctor who is experienced in his field and is very patient with his patients. He walked me through the details of my knee condition and addressed all my concerns. Thanks to Dr. Kau, I had a better understanding of my ACL and MCL injury and the various treatment options available. His advice and treatment have been very valuable to me.
Ming Lee Chua
Dr Kau was very careful and explained clearly the surgery procedures. After surgery, the care while I was in hospital was closely monitored and he even came during weekends! The hip so far has recovered and healed. His ‘predictions’ of when what can happen are so accurate. Trust him.
Teo Pek Suan Diana
I had a very successful total hip replacement done by Dr Kau 4 years ago. 4 months after the operation I was back walking, cycling and swimming. The beautiful job gave me much confidence Dr Kau is most professional and has such great doctor patient communication.

Send Us An Enquiry

If you have any enquiry, please do get in touch. Leave us a message and we will get back to you shortly.

    Full Name*

    Email Address*

    Phone Number*

    Your Message*

    For Faster Response, WhatsApp Us

    +65‎ 8757‎ 9903

    Visit Us Today

    Mount Elizabeth Novena
    Specialist Centre
    Mount Alvernia
    Farrer Park
    38 Irrawaddy Road,
    Singapore 329563
    1, #02-01 Farrer Park Station Rd,
    Connexion, Singapore 217562

    Frequently Asked Questions (FAQs)

    Do ACL tears cause permanent damage?

    If an ACL tear is not treated, it can lead to the loss of joint function in the future.

    Can an ACL tear heal on its own?

    A complete ACL tear cannot heal on its own and requires surgery. If the ACL tear is less severe, it is still important to consult an orthopaedic specialist for a recommended non-surgical treatment plan.

    How long does an ACL injury take to heal?

    After an ACL reconstruction surgery, recovery can take 9 months.