ACL Surgery & Reconstruction in Singapore

Written by Dr Gowreeson Thevendran, MBChB (Bristol), MRCS.Ed, Dip. Sports Med.Ed, FRCS.Ed (Trauma & Ortho. ), FAMS (Singapore)

What Is An ACL Tear?

An ACL tear involves the rupture of the Anterior Cruciate Ligament (ACL), a key ligament that stabilises the knee by connecting the tibia (shin bone) to the femur (thigh bone). This injury can range from partial tears, where only some ligament fibres are damaged, to complete tears, where the ligament is fully ruptured. The ACL is particularly important for balance and stability during activities such as walking, running, or jumping and is at high risk during sports requiring sharp turns, pivoting, and jumping. A complete tear often leads to instability in the knee, typically signalled by a noticeable "pop" at the time of injury, followed by swelling. Regardless of the severity, an ACL tear requires evaluation by an orthopaedic specialist to determine the appropriate treatment.

Symptoms of an ACL Tear

Following an ACL injury, you may experience the following symptoms:

  • Pain in the centre of your knee
  • Pain in the back of your leg
  • Swelling around the knee joint
  • Instability when walking or changing direction quickly
  • Difficulty squatting down without putting weight on your knees

If you suspect an ACL sprain or tear, it is crucial to seek immediate medical attention. This allows an orthopaedic surgeon trained in addressing orthopaedic injuries to assess the full extent of your condition.

Diagnosing ACL Tears: ACL Tear Grades

An orthopaedic specialist will diagnose your ACL injury through a history review and physical examination. During this exam, the specialist assesses the knee's range of motion and checks for an ACL tear. They will also examine other structures within the knee, as ACL tears often accompany damage to collateral ligaments and cartilage.

You may undergo X-rays to identify any fractures. In cases where history and physical examinations are inconclusive, magnetic resonance imaging (MRI) may be required. MRI exams further evaluate the state of the cartilage and meniscus tissue, aiding in determining the appropriate treatment.

ACL injuries are categorised based on the extent of the damage:

Grade 1

Grade 1 ACL injuries are the mildest, with the ligament suffering minor damage from overstretching but not tearing. The ligament maintains enough structural integrity to keep the knee joint relatively stable.

Grade 2

At this level, the ACL has a partial tear, indicating the ligament's fibres have been overstretched to the point of causing noticeable loosening. This reduces the ligament's ability to stabilise the knee joint fully.

Grade 3 

Grade 3 is the most severe ACL injury category, characterised by a complete tear or detachment from the bone. Due to the total loss of ligament integrity, maintaining knee stability is significantly challenging.

Non-Surgical ACL Treatments

An ACL specialist will tailor your treatment based on your symptoms, examination results, sports and activity goals, and any remaining growth in your growth plates.

RICE: Rest, Ice, Compression, and Elevation

Non-surgical treatment suits grade 1 ACL injuries, typically sprains. Rest allows natural healing, while ice and compression helps manage inflammation and swelling. Elevation of the affected leg can further aid in reducing swelling. This approach effectively manages cases where the ACL is mildly overstretched without tearing.

Physical Therapy

Grade 2 ACL tears, or partial tears, often respond well to physical therapy. A comprehensive rehabilitation programme aims to strengthen surrounding muscles, improve joint stability, and increase range of motion. Through targeted exercises, functional movement, and proprioceptive training, knee stability may be restored without surgery.

ACL Surgery

ACL reconstruction surgery is crucial for addressing complete ACL tears and stabilising unstable knees, thereby preventing long-term joint issues and eliminating the need for a knee brace. This procedure, aimed at restoring knee joint stability, is ideally performed three to six weeks after the injury to reduce inflammation and the risk of arthrofibrosis, a severe scarring response. 

During the surgery, after administering general anaesthesia to ensure you're asleep and comfortable, an ACL specialist employs knee arthroscopy techniques to address the damaged ligament. This involves a few small incisions around the knee for both the removal of the damaged ACL and the placement of the graft. The graft used to reconstruct the ACL — chosen from autografts (the patient's own tissue), allografts (donor tissue), or a hybrid of both — is carefully selected based on the patient's age, activity level and overall health, ensuring a personalised treatment plan. 

Typically taking about two hours, the process might conclude with applying steri-strips to the incisions, allowing many patients to return home the same day. This meticulous approach aims to restore stability to the knee, catering to each individual's specific needs.


Procedure: In an autograft procedure, the surgeon harvests tissue from the patient's own body, such as a tendon from the hamstring or patellar tendon, to replace the damaged ACL.

When Used: Autografts are often recommended for young, active individuals or athletes due to their lower risk of rejection and faster integration into the minimising, which are preferred for patients who may place high demands on the knee post-recovery.


Procedure: An allograft uses donor tissue, typically from a cadaver, to replace the torn ACL. This method avoids the need to harvest tissue from the patient, potentially reducing recovery time and pain at the donor site.

When Used: Allografts may be chosen for older patients or those with lower activity levels. They are also considered when a patient prefers not to have tissue harvested from their own body or in cases where multiple ligaments need repair, minimising the amount of surgical intervention on the patient's body.

Hybrid Graft

Procedure: A hybrid graft combines both autograft and allograft tissues to reconstruct the ACL. This approach may utilise the patient's tissue reinforced with donor tissue, offering a balance between the benefits of both types.

When Used: Hybrid grafts are utilised in complex cases where the patient's tissue alone may not be sufficient for a robust repair or to enhance the strength of the repair in patients with significant knee instability or those undergoing revision surgery. This method aims to maximise the repair's durability while considering the patient's specific needs and circumstances.

Dr Gowreeson Thevendran

MBChB (Bristol), MRCS.Ed, Dip. Sports Med.Ed, FRCS.Ed ( Trauma & Ortho. ), FAMS (Singapore)

Dr Gowreeson Thevendran is an orthopaedic surgeon in Singapore who specialises in lower limb orthopaedic conditions, trauma, and fracture surgeries of both the upper and lower limbs. He received his medical education from the University of Bristol and completed his surgical training in the UK and Canada. Before establishing his private practice, he served as Chief of Foot & Ankle Surgery, Department of Orthopaedics at Tan Tock Seng Hospital, Singapore.

Dr Gowreeson Thevendran’s Qualifications and Awards:

  • Bachelor of Medicine and Surgery, University of Bristol, England
  • Fellow of the Royal College of Surgeons, Edinburgh
  • Diplomate Faculty of Sports and Exercise Medicine, Royal College of Surgeons Edinburgh
  • Fellow of the Academy of Medicine, Singapore
  • SICOT PIONEER Founders Award 2020
  • 2015 European Foot & Ankle Society ‘Best Podium Presentation’ Award
  • 2013 Singapore Orthopaedic Association Junior Travelling Fellowship
  • 2012 NHG Critical Talent Special Recognition Award
  • 1998 Enid Lindt Prize in Clinical Surgery
  • 1995 Public Services Department Full Medical Scholarship

Languages Spoken:

  • English, Malay, Tamil

Frequently Asked Questions about ACL Tear & Reconstruction Surgery

1Is there a difference in recovery time between traditional ACL surgery and minimally invasive techniques?
The recovery time between traditional ACL surgery and minimally invasive techniques generally does not significantly differ. Factors affecting recovery include the individual's health, the surgical approach, the extent of the ACL injury, and adherence to post-operative care and rehabilitation protocols.
2Is ACL reconstruction surgery always necessary for a complete tear?
While ACL reconstruction surgery is commonly recommended for complete tears, it is not always mandatory. Non-surgical options may suffice for those with a less active lifestyle or minor tears willing to commit to intensive rehabilitation. However, surgery is often suggested to avoid further joint damage for individuals keen on returning to high-demand activities.
3What are the causes of ACL tears?

ACL tears can affect anyone, not just athletes, and may sideline an individual for months. These injuries commonly occur due to:

  • Sudden stops or changes in direction
  • Direct impacts, such as collisions with another player
  • Landing awkwardly from a jump

Several factors can elevate the risk of an ACL sprain or tear:

  • Participation in contact sports like football, soccer, and basketball
  • Recreational activities, including skiing
  • Insufficient conditioning before engaging in intense exercise or sports
  • Execution of improper movement patterns
  • Wearing ill-fitting footwear
  • Using worn-out or poorly maintained sports equipment

Due to the difficulty of healing an ACL independently, it is essential to consult an orthopaedic specialist or sports injury doctor in Singapore for proper care and treatment.

4What happens if ACL tears are left untreated?
Untreated ACL tears can lead to chronic instability, ongoing discomfort, and a heightened risk of additional knee injuries. The body might compensate for a torn ACL to some extent, but this compensation can exacerbate joint issues over time. Prompt consultation with an orthopaedic specialist is crucial to prevent these adverse outcomes and maintain joint health.
5What are the risks or complications of ACL reconstruction surgery?
ACL reconstruction carries inherent risks and complications, as does any surgery. Understanding these risks is vital to making an informed decision. Potential issues include infection, blood clot formation, and variations in knee function post-recovery. A detailed conversation with your orthopaedic surgeon is essential to assess these risks. They will tailor advice to your situation, employ strategies to minimise risks and support your journey towards successful rehabilitation.
6Is it okay to walk on a torn ACL?
While walking on a torn ACL is technically possible, it is generally advised against. A torn ACL compromises the knee's stability, risking further damage and injury during weight-bearing activities. Walking without the support of a brace or crutches may worsen the condition and increase additional injury risks.
7Can an ACL tear lead to the development of osteoarthritis in the knee?
An ACL injury heightens the risk of developing osteoarthritis in the knee, a risk that persists even after ligament reconstruction surgery. Factors influencing the onset of osteoarthritis include the severity of the injury, any concurrent knee injuries, and your physical activity levels post-treatment. Consulting with your ACL surgeon for a long-term management plan is crucial.
8Can a first-degree ACL tear heal without surgery?
First-degree ACL tears, characterised by mild ligament stretching without actual tearing, can sometimes heal without surgical intervention. Nevertheless, the healing likelihood without surgery is generally lower for such injuries. Non-surgical treatments like rest, physical therapy, and bracing might be recommended to alleviate pain and manage symptoms. Despite these measures, the potential for ongoing instability exists, underscoring the importance of continuous monitoring.
9Does insurance and medisave cover ACL surgery?
Coverage for ACL surgery in Singapore may vary by the procedure and your specific policy. Patients are advised to consult the clinic to verify MediSave eligibility and insurance coverage.

Clinic Location


OrthofootMD@Mount Alvernia Hospital