If you’ve torn your ACL and aren’t sure whether surgery is the right choice, this article will help you understand your treatment options and what could happen if you decide against surgery.

What is the Anterior Cruciate Ligament (ACL)?
The anterior cruciate ligament (ACL) is a crucial band of tissue in your knee that connects your thigh bone (femur) to your shin bone (tibia). It keeps your knee stable by preventing the shinbone from sliding too far forward or twisting abnormally.
Anterior cruciate ligament injuries can significantly impair knee stability and function. These injuries are among the most common knee ligament issues, particularly in young athletes.
When ACL injuries occur, they may involve either complete or partial tears, which can compromise the entire knee structure if left untreated. A torn ACL affects not only mobility but also long-term joint integrity if not properly treated.
What Causes ACL Tears
ACL tears occur when there is sudden forceful movement, such as pivoting, landing incorrectly, or direct trauma to the knee joint. If you’re active in sports or high-impact activities, you’re immediately at higher risk due to the possibility of sports injuries. With a damaged ACL, continuing strenuous exercise can result in meniscus and cartilage injuries, leading to chronic knee pain.
Luckily, ACL tears can be treated surgically or non-surgically (with physical therapy and other options). Most people opt for ACL surgery, but some choose alternative therapies as well. Tendon grafts, such as the patellar tendon, hamstring tendon autograft, and quadriceps tendon autograft, are used in the surgical treatment of ACL tears to reconstruct the ligament.
Signs and Symptoms of ACL Injuries
You might have torn your ACL if you experience:
- Intense knee pain that comes on suddenly
- Significant swelling that develops quickly
- A worrisome feeling that your knee might buckle or “give way”
- Your knee actually collapsing during movements like pivoting or stopping abruptly
The ACL is one of your knee’s most important stabilisers. Even a partial tear can make everyday movements like walking or climbing stairs difficult. With a complete tear, you’ll likely notice:
- Your knee feels unreliable during normal activities
- Simple tasks like getting out of a chair become challenging
- Returning to sports seems impossible without proper treatment
Non-Surgical Treatment for ACL Injuries
Patients with partial ACL tears or lower activity levels may be candidates for non-surgical management. Conservative treatment typically involves the R.I.C.E. protocol (rest, ice, compression, elevation) combined with targeted physical therapy to strengthen muscles around the knee. A functional knee brace can provide additional joint stabilisation during activity. Particular emphasis should be placed on hamstring strengthening, as this is critical for both prehabilitation and postoperative rehabilitation to optimise knee function. These approaches can effectively reduce pain and inflammation.
However, it’s important to note that non-surgical management does not restore the anatomical ACL. Functional capacity often remains below pre-injury levels, with persistent instability risks during high-demand activities. While partial tears may initially respond to conservative treatment, doctors should advise patients about the significant risk of progression to complete rupture without a successful ACL surgery.
When to Know if You Need ACL Surgery
Surgery may be recommended if non-surgical treatments fail to restore knee function, or if the individual experiences instability in the knee joint, leading to a risk of further injury. It is important to note that a torn ACL does not heal on its own due to its poor blood supply. Thus, ACL reconstruction surgery is often the best option to restore stability to the knee and reduce the risk of further damage to the knee joint, including the meniscus, articular cartilage and ligaments.
Orthopaedic surgeons typically recommend ACL reconstruction when conservative measures prove insufficient to restore knee stability. The decision to proceed with surgery depends on several key factors: the patient’s activity level and functional requirements, the severity of the ACL injury (whether a partial or complete ACL tear), the patient’s overall health status, and their rehabilitation potential. While age is an important consideration in surgical planning, it should not be viewed as an absolute limiting factor. Ultimately, the treatment approach must be tailored to each patient’s unique clinical presentation and lifestyle needs.
Early ACL reconstruction surgery creates a more stable healing environment for the knee and may reduce the risk of secondary injuries, such as meniscus or cartilage damage.
What Happens During Reconstructive ACL Surgery
ACL reconstruction is a carefully planned surgery that’s customised to fit your body and activity level. It’s the most common and effective surgery for a torn ACL. Here’s what happens during the surgical procedure:
- Your surgeon will replace your torn ACL with new tissue called a “graft”
- This graft can come from:
- Your own body (usually from your knee’s patellar tendon, hamstring tendons, or quadriceps tendon)
- A donor (processed and sterilised tissue)
The hamstring tendon option (using tendons from your inner thigh) is a popular choice that many surgeons recommend because it tends to work well and has good recovery outcomes.
ACL reconstructive surgery is designed to restore knee stability and function, allowing individuals to return to physical activity. The procedure aims to prevent further degeneration of the knee and support long-term joint health.
ACL Surgery Techniques
ACL surgery is generally performed through knee arthroscopy, a type of minimally invasive surgery involving small incisions and a camera for visual guidance. ACL reconstructions are commonly performed using either autografts or allografts, with graft choices varying based on patient needs and suitability. Options include the patellar tendon group, hamstring autograft ACL reconstruction, semitendinosus hamstring tendon, patient’s quadriceps tendon, and occasionally the Achilles tendon. The choice often depends on the surgical leg, activity level and anatomy.
Before graft placement, the torn ACL stump is often removed to ensure a clean surgical field. This step helps facilitate proper graft attachment and minimises the risk of complications during the procedure.
What You Need to Know About Avoiding ACL Tear Surgery
If you’re experiencing knee pain and swelling and suspect an ACL tear, it’s vital to have your knee evaluated by a healthcare provider. Proper diagnosis is essential to understand whether your torn ACL can heal without surgery. Delaying treatment increases the risk of further damage to your knee joint.
Aside from the ACL tear itself, there may be additional injuries to other ligaments or the meniscus. Your doctor will likely recommend resting and icing the affected area after properly diagnosing the condition. They may also emphasise keeping weight off the injured knee in the early stages of healing. However, if you delay consultation or ignore the prescribed rehabilitation, your condition can worsen. Timely treatment is crucial to prevent further complications.
There are several treatment options available for ACL tears, including:
- Rehabilitation protocols
- Platelet-rich plasma (PRP) therapies
- Stem cell therapies (BMAC, MSCs)
- ACL reconstruction surgery
While non-surgical treatments can help alleviate pain and discomfort, surgery remains a critical option for restoring knee stability and preventing further damage to the knee’s structures. Research shows that some patients who initially try rehabilitation, especially those with active lifestyles, may still require surgery due to persistent instability or the sensation of the knee “giving way”. Active individuals, particularly young athletes, should consider ACL reconstruction to protect the meniscus and cartilage inside the knee. That said, some patients will still rely on a functional knee brace when returning to sports.
Before committing to surgery, you may want to explore non-surgical treatments in the short term, though it’s important to understand the long-term consequences of living with an untreated ACL tear. Being aware of the potential risks can help you make informed decisions about your treatment options.
The following outlines the downsides of not having surgery for an ACL tear:
1. Feeling Unstable
If you have a torn ACL and do not undergo ACL surgery, your knee joint will remain unstable, which will significantly restrict your participation in sports, employment, and daily activities that require knee stability. Quick rotations, sudden changes in direction, and jumping can feel unmanageable and may worsen your knee instability.
2. Risk of Tearing Your Meniscus
In addition to the ACL injury, a torn ACL increases the risk of meniscus tears, which is the cartilage in the knee joint. When the ACL is ruptured, abnormal movement of the knee places extra stress on the meniscus. This added strain raises the likelihood of meniscus and articular cartilage injuries, which can lead to significant knee pain and instability. If left untreated, the risk of developing osteoarthritis in the knee joint increases, particularly if the meniscus is damaged.
3. Risk of Osteoarthritis
One of the long-term risks of untreated ACL tears is the development of osteoarthritis. Damage to the meniscus and the ACL can lead to the breakdown of articular cartilage in the knee joint, causing pain, stiffness and swelling. As the cartilage thins and the bones rub together, bone spurs can form, exacerbating knee pain. ACL surgery, particularly early ACL reconstruction, helps restore knee stability to the knee joint and can help prevent the progression of osteoarthritis by preserving the meniscus and cartilage. Cartilage injury often accompanies ACL tears and contributes to long-term joint degeneration.
4. Long-Term Instability in the Knee
If a torn ACL is left untreated, chronic knee instability can develop. This instability can lead to long-term knee pain and dysfunction, and eventually, a reduced quality of life. If ACL surgery is not pursued, you may need to adjust your physical activities, avoiding sports or activities that place stress on the knee joint. However, this is often not a viable long-term solution, as untreated ACL tears typically lead to continued instability and degeneration of the knee joint, affecting overall health.
5. Frequent Pain and Swelling
Without proper ACL treatment, pain and swelling may persist, especially if the knee continues to be used heavily. As the ligament deteriorates further, the knee becomes more prone to recurrent swelling and discomfort. Individuals with untreated ACL tears may experience permanent pain that interferes with daily activities, and the recovery process can become progressively more difficult.
6. Uncertainty with Non-Surgical Treatments
Many individuals who do not opt for ACL surgery first attempt physical therapy to alleviate symptoms. While physiotherapy can help reduce pain and restore strength and mobility, it cannot fully address the instability caused by a torn ACL. In most cases, the knee will never return to its pre-injury state without surgery, especially for those who wish to return to sports or physical activities that require knee stability. ACL reconstruction provides the best chance for restoring full knee joint function and avoiding long-term knee pain and disability.
Additional Points
Continuing to engage in high-level sports with an ACL-deficient knee can lead to permanent damage, requiring long-term management. Regardless of whether you choose surgery, it is essential to consult with a healthcare professional for proper evaluation and guidance.
The effectiveness of PRP and other injection therapies for ACL tears remains controversial, and these treatments may not significantly alter the long-term outcomes.
For professional advice and comprehensive treatment, contact us to discuss your goals with a qualified doctor. Hip & Knee Orthopaedics in Singapore offers thorough and personalised treatment plans for individuals experiencing knee injuries under various circumstances.
Potential Risks and Complications of Anterior Cruciate Ligament Surgery
Although ACL surgery is generally safe, it does come with some risks, including infection, graft failure, and complications related to anaesthesia. Patients must also be aware that ACL reconstruction surgery is not an instant fix. It requires a period of rehabilitation to ensure the ACL graft heals properly and the knee regains full strength.
Additionally, some patients may experience knee stiffness, limited range of motion, or issues with the graft, particularly if the surgery is performed incorrectly or the patient does not follow post-operative rehabilitation protocols. Consistent adherence to rehabilitation guidelines is needed to achieve optimal recovery and reduce the risk of complications.
Recovery After ACL Surgery
Post-operative recovery after ACL reconstruction typically includes a combination of physical therapy, rest and gradual reintroduction of activity. After surgery, wearing a protective knee brace can aid in safe mobilisation; a hinged knee brace can offer added stability during recovery and may be prescribed following ACL reconstruction. Rigorous physical therapy is essential to regain strength and knee range of motion.
Depending on the type of graft used (patellar tendon, hamstring tendon autograft, or quadriceps tendon), recovery times can vary. Full recovery may take several months, but most patients can return to their usual level of activity after 6–12 months, assuming they follow their physical therapist’s instructions and undergo proper rehabilitation. Most of the time, return to low-impact activities can commence earlier, as dictated by the doctor or physical therapist.
Your Health is Our Priority
Dealing with an untreated ACL tear? Over time, it can cause ongoing knee weakness, worsening pain, and even lead to more serious issues like cartilage damage or arthritis. While physical therapy and other non-surgical options might help manage symptoms, surgery is often the most reliable way to fully restore knee strength—especially if you’re active or play sports.
If you’re unsure about the right next steps, don’t put it off—get professional medical advice. At Hip & Knee Orthopaedics in Singapore, we create custom treatment plans to help you recover safely and get back to doing what you love.
Contact us today to book a consultation with our specialists and explore your options.