

What Is An ACL Injury?
ACL or anterior cruciate ligament is one of four knee ligaments that are critical to the stability of your knee joint. Your ACL is made of sturdy fibrous material and functions to control excessive knee motion by limiting joint mobility.
One of the most common problems involving the knee joint is an anterior cruciate ligament injury or ACL tear. Of the four major knee ligaments of the knee, an ACL injury or rupture is the most debilitating knee ligament injury.
What Causes an ACL Injury?

An ACL injury is usually a sports-related knee injury. About 80% of sports-related ACL tears are “non-contact” injuries. Non-contact means that the damage occurs without the contact of another player, such as a tackle in football.
Most often, ACL tears occur when pivoting or landing from a jump. Your knee gives out from under you once you tear your ACL.
Female athletes are known to have a higher risk of an ACL tear while participating in competitive sports. Unfortunately, understanding why women are more prone to ACL injury is unclear. There are some suggestions it is biomechanical, strength and hormonally related. In truth, it is probably a factor of all three.
What Sports Have A High Incidence Of ACL Injuries?
Many sports require a functioning ACL to perform joint manoeuvres such as cutting, pivoting, and sudden turns.
These high demand sports include football, rugby, netball, touch, basketball, tennis, volleyball, hockey, dance, gymnastics and much more. You may be able to function in your normal daily activities without an intact standard ACL, but these high-demand sports may prove difficult.
Therefore, athletes contemplate the decision to undergo surgery to return to their previous level of competition. ACL injuries can curtail many promising sporting careers.
What are the Symptoms of an ACL Injury?
Several methods make the diagnosis of an ACL tear. Patients who have an ACL tear commonly sustain a sports-related knee injury.
They may have felt or heard a “pop” in their knee, and the knee usually gives out from under them. ACL tears cause significant knee swelling and pain.
How is an ACL Injury Diagnosed?
On clinical knee examination, your physiotherapist or sports doctor will look for signs of ACL ligament instability. These special ACL tests place stress on the anterior cruciate ligament and can detect an ACL tear or rupture.
An MRI may also be used to determine if you have an ACL tear. It will also look for signs of any associated injuries in the knee, such as bone bruising or meniscus damage, that regularly occur in combination with an ACL tear.
X-rays are of little clinical value in diagnosing an ACL tear.
For more information, please ask the advice of your knee surgeon or sports physiotherapist.
ACL Injury Treatment
Many patients with an ACL tear start to feel better within a few days or weeks of an ACL injury. These individuals may feel as though their knee is healthy again because their swelling has started to settle. However, this is when your problems with knee instability and giving way may start or worsen.
ACL tears do not necessarily require ACL reconstruction surgery. There are several important factors to consider before deciding to undergo ACL reconstruction surgery.
- Your age?
- Do you regularly perform sports or activities that generally require a functional ACL?
- Do you experience knee instability?
- What are your plans for the future?
If you don’t participate in a multi-directional sport that requires a patent ACL, and you don’t have an unstable knee, then you may not need ACL surgery.
Physiotherapy & ACL Exercises
Your best way to avoid ACL reconstructive surgery is to undertake a comprehensive ACL-Deficient Knee Rehabilitation Program. This comprehensive exercise-based program involves leg strengthening, proprioception and high-level balance retraining, plus sport-specific agility and functional enhancement. Your sports physiotherapist is an expert in the prescription of ACL tear exercises.
PhysioWorks has developed a specific ACL Deficient Knee Rehabilitation Program to address ACL injuries for the patient who wishes to avoid or delay ACL reconstructive surgery.
Your physiotherapy treatment will aim to:
- Reduce pain and inflammation.
- Normalise your joint range of motion.
- Strengthen your knee: esp Quadriceps (esp VMO) and Hamstrings.
- Strengthen your lower limb: Calves, Hip and Pelvis muscles.
- Improve patellofemoral (kneecap) alignment
- Normalise your muscle lengths
- Improve your proprioception, agility and balance
- Improve your technique and function, e.g. walking, running, squatting, hopping and landing.
- Minimise your chance of re-injury.
We strongly suggest that you discuss your knee injury after a thorough examination from a knee injury clinician such as a sports physiotherapist, sports physician or knee surgeon.
Non-Operative vs ACL Reconstruction
For more information please read this article: ACL Reconstruction vs Exercise Management
How to Prevent an ACL Injury?
Preventing an ACL tear has been the focus of recent research, especially the prevention of ACL tears in female athletes. Numerous theories propose to explain why people may tear their ACL and how they can prevent.
Current investigations have focused on neuromuscular training to prevent ACL tears. We know that ACL reconstruction patients who undertake extensive post-operative physiotherapy rehabilitate exceptionally well. The question remains. If you conduct similar ACL exercises, can they prevent an ACL tear in the first place? For more advice, please consult with your sports physiotherapist.
ACL Surgery
Surgery for an ACL tear is called an ACL reconstruction. A repair of the anterior cruciate ligament is rarely a possibility, and thus the ACL is reconstructed using another tendon or ligament to substitute for the torn ligament. There are several options for how to perform ACL surgery.
The most important choice is the type of graft used to reconstruct the torn ACL. There are also variations in the procedure, such as the new ‘double-bundle’ ACL reconstruction.
Risks of ACL surgery include:
- infection,
- persistent instability and pain
- knee stiffness, and
- difficulty returning to your previous level of activity.
The good news is that better than 90% of patients have no complications with ACL surgery.
Post-Surgical ACL Rehabilitation
Post-operative ACL rehabilitation is one of the most important, yet too often neglected, aspects of ACL reconstruction surgery. The most successful and quickest outcomes result from the guidance and supervision of an experienced Sports Physiotherapist.
Your rehabilitation following ACL surgery focuses on restoring full knee motion, strength, power and endurance. You’ll also require balance, proprioception and agility retraining individualised towards your specific sporting or functional needs.
Your sports physiotherapist is an expert in this field. We suggest that you contact them for the best advice in your circumstances.
ACL Injuries in Children
ACL reconstruction surgery is the standard treatment for young, active people who sustain an ACL tear. But what happens when you’re young and your bones are still growing?
Should ACL surgery be delayed until the child is older, or should ACL reconstruction occur before skeletal maturity? In this scenario, additional surgery may take place at skeletal maturity.
The concern of performing ACL surgery in children is that there is a risk of causing a growth disturbance in growing children. Growth plate problems as a result of ACL surgery could potentially lead to early growth plate closure or alignment deformities.
However, recent research is showing that the risk of growth plate problems and meniscal damage is potentially less than the risk of permanent knee damage if the ACL surgically-repaired.
Your knee surgeon is the best person to discuss whether ACL reconstruction is advisable or not.
Return to Sports with an ACL Injury
Athletes often have particular difficulty returning to their sport once they have sustained an ACL injury, even if they undergo surgical reconstruction.
Researchers have found that your best chance of returning to your sports post-ACL tear is to have undertaken both:
- ACL reconstruction surgery, and intensive post-operative physiotherapy rehabilitation, or
- No Surgical ACL Physiotherapy
For more information, please ask the advice of your knee surgeon or knee physiotherapist, who is up to date with the latest in the pros and cons of both ACL treatment approaches.
Common Causes - Knee Pain
Knee pain can have many origins from local injury, referred pain, biomechanical issues and systemic issues. While knee pain can appear simple to the untrained eye, a thorough assessment is often required to ascertain the origin of your symptoms. The good news is that once a definitive diagnosis is determined, most knee pain quickly resolves with the correct treatment and rehabilitation.
Knee Ligament Injuries
- Knee Ligament Injuries
- ACL Injury
- PCL Injury
- MCL Sprain
- LCL Sprain
- Posterolateral Corner Injury
- Superior Tibiofibular Joint Sprain
Knee Meniscus Injuries
Kneecap Pain
- Chondromalacia Patella
- Fat Pad Syndrome
- Patella Dislocation
- Patellofemoral Pain Syndrome
- Osgood Schlatter’s Disease
- Sinding Larsen Johansson Syndrome
Knee Arthritis
Knee Tendon Injuries
Muscle Injuries
- Corked Thigh
- Thigh Muscle Strain
- Hamstring Strain
- ITB Syndrome
- Popliteus Syndrome
- Muscle Strain (Muscle Pain)
- Cramps
- DOMS – Delayed Onset Muscle Soreness
Knee Bursitis
Children’s Knee Conditions
Other Knee-Related Conditions
- Runner’s Knee
- Plica Syndrome
- Fibromyalgia
- Stress Fracture
- Overuse Injuries
- Restless Legs Syndrome
- Sciatica
Knee Surgery
For specific information regarding your knee pain, please seek the assistance of a healthcare professional with a particular interest in knee condition, such as your physiotherapist.
What is Physiotherapy Treatment?
Physiotherapists help people affected by illness, injury or disability through exercise, manual joint therapy, soft tissue techniques education and advice. Physiotherapists maintain physical health, help patients to manage pain and prevent disease for people of all ages. Physiotherapists help to encourage pain-relief, injury recovery, enabling people to stay playing a sport, working or performing activities of daily living while assisting them to remain functionally independent.
There is a multitude of different physiotherapy treatment approaches.
Acute & Sub-Acute Injury Management
Hands-On Physiotherapy Techniques
Your physiotherapist's training includes hands-on physiotherapy techniques such as:
- Joint Mobilisation (gentle joint gliding techniques)
- Joint Manipulation
- Physiotherapy Instrument Mobilisation (PIM)
- Minimal Energy Techniques (METs)
- Massage
- Soft Tissue Techniques
Your physiotherapist has skilled training. Physiotherapy techniques have expanded over the past few decades. They have researched, upskilled and educated themselves in a spectrum of allied health skills. These skills include techniques shared with other healthcare practitioners. Professions include exercise physiologists, remedial massage therapists, osteopaths, acupuncturists, kinesiologists, chiropractors and occupational therapists, just to name a few.
Physiotherapy Taping
Your physiotherapist is a highly skilled professional who utilises strapping and taping techniques to prevent and assist injuries or pain relief and function.
Alternatively, your physiotherapist may recommend a supportive brace.
Acupuncture and Dry Needling
Many physiotherapists have acquired additional training in the field of acupuncture and dry needling to assist pain relief and muscle function.
Physiotherapy Exercises
Physiotherapists have been trained in the use of exercise therapy to strengthen your muscles and improve your function. Physiotherapy exercises use evidence-based protocols where possible as an effective way that you can solve or prevent pain and injury. Your physiotherapist is highly-skilled in the prescription of the "best exercises" for you and the most appropriate "exercise dose" for you depending on your rehabilitation status. Your physiotherapist will incorporate essential components of pilates, yoga and exercise physiology to provide you with the best result. They may even use Real-Time Ultrasound Physiotherapy so that you can watch your muscles contract on a screen as you correctly retrain them.
- Muscle Stretching
- Core Exercises
- Strengthening Exercises
- Neurodynamics
- Balance Exercises
- Proprioception Exercises
- Real-Time Ultrasound Physiotherapy
- Swiss Ball Exercises
Biomechanical Analysis
Biomechanical assessment, observation and diagnostic skills are paramount to the best treatment. Your physiotherapist is a highly skilled health professional. They possess superb diagnostic skills to detect and ultimately avoid musculoskeletal and sports injuries. Poor technique or posture is one of the most common sources of a repeat injury.
Hydrotherapy
Aquatic water exercises are an effective method to provide low bodyweight exercises.
Sports Physiotherapy
Sports physio requires an extra level of knowledge and physiotherapy skill to assist injury recovery, prevent injury and improve performance. For the best advice, consult a Sports Physiotherapist.
Vestibular Physiotherapy
Women's Health
Women's Health Physiotherapy is a particular interest group of therapies.
Workplace Physiotherapy
Not only can your physiotherapist assist you in sport, but they can also help you at work. Ergonomics looks at the best postures and workstation set up for your body at work or home. Whether it be lifting technique improvement, education programs or workstation setups, your physiotherapist can help you.
Electrotherapy
Plus Much More
Your physiotherapist is a highly skilled body mechanic. A physiotherapist has particular interests in certain injuries or specific conditions. For advice regarding your individual problem, please contact your PhysioWorks team.
ACL Tear
An ACL (Anterior Cruciate Ligament) tear most often occurs during sporting activities when an athlete suddenly pivots, causing excessive rotational forces on the ligament. Individuals who experience ACL tears describe a feeling of the joint giving out, or buckling. You'll commonly hear a "pop."Signs You May Have Sustained an ACL Tear:
- Sudden giving way of the knee
- Hearing a 'pop' at the time of injury
- Sudden swelling of the knee joint
- Pain in the knee when walking
How is an ACL Tear Diagnosed?
A well trained Sports Physiotherapist, Sports Physician or Orthopaedic Surgeon will generally be able to confirm the diagnosis of an ACL tear within the clinic and from your injury history. An MRI scan can confirm your ACL tear and identify other knee injuries that may have occurred when your ACL was ruptured. These accessory injuries commonly include meniscal tears, bone bruising and collateral ligament injuries. Confirmation of an ACL tear is essential since the treatment differs from a common knee ligament strain or a meniscus tear.What to do if have a Ruptured ACL?
Please be guided by your trusted healthcare practitioner for an ACL tear. Successful rehabilitation options vary depending on your age, activity level and extent of the injury. For specific advice, please consult your physiotherapist, knee surgeon or doctor.Why are ACL Tears Such a Big Problem?
When an ACL injury occurs, the knee becomes less stable. The ACL injury is a problem because this instability can make sudden, pivoting movements difficult, and it may make the knee more prone to developing arthritis and cartilage tears. If your knee is unstable, a common complaint of a sensation that the knee will 'give out' from under them. When this giving way sensation is because of an ACL injury, the knee joint is sliding too much. Joint sliding can be a problem because each episode of instability (the 'giving way' sensation) can cause damage to the knee cartilage. Therefore an ACL injury makes patients more prone to developing arthritis and meniscus tears. Athletes often have particular difficulty once they have sustained an ACL injury. Many sports require a functioning ACL to perform common manoeuvres such as cutting, pivoting, and sudden turns. These high demand sports include, but are not limited to:- Football
- Soccer
- Basketball
- Skiing
- Gymnastics
- Hockey (Ice and Field)
- Wrestling
- Lacrosse
- Rugby
ACL Tear? Things to Consider.
Patients who suspect they have an ACL tear should seek a professional assessment by their physiotherapist or sports doctor. An ACL tear may be misdiagnosed immediately after the injury because of associated pain and swelling. There may also be muscle spasm that contributes to making the knee challenging to examine. Therefore, it may not be possible to conclusively determine the presence of an ACL tear soon after the injury. If an ACL tear is suspected, you will return for a follow-up evaluation with your orthopaedic surgeon.How Does Your Physiotherapist Make the Diagnosis of an ACL Tear?
The presence of a suspected ACL tear occurs whenever a patient has an injury to their knee. In the clinic, knee instability assessment occurs via specific manoeuvers performed by your physiotherapist or doctor. These manoeuvers test the function of the ligament to determine if an ACL tear is present. The most commonly used tests to determine the presence of an ACL tear include the Lachman Test and the Pivot Shift Test.What are Other Tests Recommended to Diagnose an ACL Tear?
A complete examination of the knee is also necessary to determine if other injuries may have occurred that could be causing your symptoms. Your physiotherapist or doctor will also evaluate X-rays of the knee to assess for any possible fractures, and an MRI may evaluate ligament or cartilage damage. However, MRI studies may not be needed to diagnose an ACL tear. The physical examination and history are just as good as an MRI in diagnosing an ACL tear. Many patients are concerned when their doctor or physiotherapist does not order an MRI. While the MRI may be necessary in some cases, it is not required to diagnose most ACL tears, if there are laxity and a predisposing mechanism of injury.What to do if have a Ruptured ACL?
We recommend professional guidance for an ACL tear. Successful rehabilitation options vary depending on your age, activity level and extent of the injury.ACL Surgery
The decision as to whether or not to operate on an ACL tear is dependent on several factors. Some patients who experience ACL tears can resume normal daily activities without surgical reconstruction of this ligament. There are some important factors to consider in deciding as to whether or not operative treatment of an ACL tear is needed. These factors include the age of the patient, the activity level of the patient (both recreational and occupational), the expectations of the patient, the ability and willingness of the patient to undertake postoperative rehabilitation. Plus, the degree of instability of the joint, and any other associated injuries to the knee (e.g. other ligamentous or meniscal problems).What is the Surgical Treatment for ACL Reconstruction?
ACL reconstruction is usually not performed until several weeks after the injury. Studies have shown improved results when ACL reconstruction surgery is delayed several weeks from the time of injury. This time allows the inflamed and irritated knee to cool down. Swelling decreases, inflammation subsides, and range of motion improves. Resolution of swelling and stiffness before ACL reconstruction surgery improves the postoperative function of the joint.Can the ACL be Repaired?
ACL reconstruction surgery is common, and improperly, referred to as an ACL repair. Unfortunately, a torn ACL cannot be "repaired." Rather, the torn ligament's replacement is healthy graft tissue. It is not possible to repair the torn ACL by simply reconnecting the torn ends.How is the ACL Reconstruction Performed?
The surgical procedure for an ACL reconstruction is variable but commonly involves using a segment of another larger ligament or tendon to replace the damaged ACL. The graft options for ACL reconstruction include: Hamstring Tendons Patellar Ligament Peroneus longus tendon Allograft (Donor Tissue) The ACL reconstruction surgery lasts about 1 1/2 to 2 hours, depending on the graft choice and any other work that may need to be done in the knee joint. Your physiotherapist will coordinate your postoperative rehabilitation and guidance.What to do if have a Ruptured ACL?
We highly recommend professional medical for an ACL tear. Successful rehabilitation options vary depending on your age, activity level and extent of the injury.ACL Reconstruction Rehabilitation

