Conditions

Anterior Cruciate Ligament Tears

The hustle and bustle of daily life often lulls us into a sense of comfort as we move through our routines. However, sometimes, everyday activities are disrupted by discomfort. Plantar Fasciitis, a frequently encountered orthopaedic problem, can turn the most basic tasks into agonising ordeals.

If you’ve ever winced at that sharp, stabbing pain under your foot, particularly during those initial morning steps, know you’re not alone. This relentless ailment touches the lives of countless individuals worldwide, casting a profound shadow on their quality of life.

What Is ACL?

The ACL, or Anterior Cruciate Ligament, is one of the major ligaments in the human knee joint. Ligaments are strong, fibrous bands of tissue that connect bones. In the knee, the ACL specifically connects the femur (thigh bone) to the tibia (shin bone) and is critical in stabilising the joint.

The ACL is responsible for preventing excessive forward movement of the tibia to the femur and helps control the knee’s rotational stability. This ligament is crucial for the proper functioning and stability of the knee during activities that involve cutting, pivoting, and sudden changes in direction, such as those in sports like soccer, basketball, and skiing.

Causes of ACL

Anterior Cruciate Ligament (ACL) injuries typically occur due to sudden, forceful, or awkward movements involving the knee. The most common causes of ACL injuries include:

Sports Activities

ACL injuries are frequently associated with sports that involve quick changes in direction, jumping, and sudden stops. Sports such as soccer, basketball, football, skiing, and tennis carry a higher risk of ACL injuries.

Non-Contact Movements

Many ACL injuries occur during non-contact situations where an individual abruptly changes direction, pivots, or lands awkwardly from a jump. The ligament can be strained or torn when excessive force is placed on the knee during these movements.

Direct Impact

A direct blow or impact to the knee, such as a tackle in football or a collision during a sporting event, can cause ACL injuries. These are often contact-related ACL injuries.

Sudden Stops and Twists

When a person suddenly stops while running or changes direction, often during sports or physical activities, it can lead to knee twisting, potentially causing an ACL injury.

Landing Incorrectly

Athletes may land improperly after a jump in sports like gymnastics, leading to ACL injuries.

Overextension

Hyperextending or putting excessive pressure on the knee can lead to ACL injuries. This can occur when the knee is bent backwards beyond its normal range of motion.

Gender and Anatomy

Some studies suggest that females may be more prone to ACL injuries than males, possibly due to differences in muscle strength, joint laxity, and body mechanics. Additionally, certain anatomical factors, such as a narrower notch in the femur, can increase the risk of ACL injuries.

Previous ACL Injuries

Even if treated and healed, a prior ACL injury can increase the risk of re-injury in the same or opposite knee.

Fatigue and Muscle Imbalance

Muscular fatigue and imbalances between the quadriceps and hamstring muscles can increase the likelihood of ACL injuries by impairing knee joint stability.

Signs and Symptoms of ACL

An anterior cruciate ligament (ACL) injury can manifest with various signs and symptoms, ranging from mild to severe. The most common signs and symptoms of an ACL injury include:

Pain

Pain in the knee is a typical symptom of an ACL injury. The pain may range from mild to severe and is often described as a sharp or stabbing sensation. It can be felt immediately after the injury or develop gradually over time.

Swelling

Swelling of the knee is a common and often rapid response to an ACL injury. The knee joint may become noticeably swollen due to inflammation within a few hours of the injury.

Instability

A feeling of knee instability is a hallmark of ACL injury. Patients often report a sensation of the knee “giving way” or feeling unstable, particularly when trying to pivot, change direction, or put weight on the affected leg.

Audible "Pop" or "Snap"

Limited Range of Motion

An ACL injury can lead to a reduced range of motion in the knee. The knee may be more difficult to extend or bend fully.

Difficulty Walking

Many individuals with an ACL injury experience difficulty walking, particularly in the initial stages after the injury. This can be due to pain, swelling, and instability.

Bruising

Some individuals may develop bruising around the knee joint or lower thigh in the days following the injury.

Tenderness

The area around the ACL may be tender to the touch, and there can be localised pain when pressure is applied.

Inability to Bear Weight

Severe ACL injuries may render the affected leg unable to bear weight. Walking or putting weight on the injured leg may be extremely painful and difficult.

Diagnosis of ACL

Diagnosing an anterior cruciate ligament (ACL) injury typically involves a combination of clinical evaluation, medical history, physical examination, and imaging studies. Here’s an overview of the steps involved in diagnosing an ACL injury:

Medical History

The healthcare specialist will take a detailed medical history. They will inquire about the circumstances surrounding the injury, including the mechanism of injury, any popping or snapping sounds or sensations, and the onset and duration of symptoms.

Physical Examination

A thorough physical examination of the knee is conducted. During the examination, the healthcare specialist will assess the following:

Range of motion – To check for any limitations in knee movement.
Joint stability – To assess the degree of joint laxity and the presence of any abnormal movement in the knee.
Pain and tenderness – To identify areas of pain and tenderness in and around the knee.
Swelling and effusion – To assess the degree of knee swelling.

Lachman Test

This is one of the key clinical tests used to evaluate the integrity of the ACL. The healthcare specialist will gently stabilise the thigh while pulling the tibia forward. Increased forward movement of the tibia compared to the uninjured knee may indicate an ACL tear.

Drawer Test

In this test, the healthcare specialist will assess the anterior-posterior stability of the knee. The tibia is moved forward and backwards relative to the femur. Excessive forward movement can suggest an ACL injury.

Pivot Shift Test

This test assesses the degree of knee instability when the knee is rotated. The healthcare specialist will bend the knee while applying a twisting force, looking for abnormal movement or a “clunk.”

Imaging Studies

While a clinical examination can strongly suggest an ACL injury, imaging studies are typically used to confirm the diagnosis and assess the extent of the damage. The most common imaging methods include:

Magnetic Resonance Imaging (MRI) – MRI provides detailed images of the internal structures of the knee, including the ACL. It can confirm the diagnosis, reveal the extent of the injury, and help identify any associated damage to other structures in the knee, such as meniscus tears.

Types of ACL

Anterior Cruciate Ligament (ACL) injuries are typically classified into different types based on the severity and extent of the damage to the ligament. The two primary types of ACL injuries are:

Partial ACL Tear

Only a portion of the ligament is damaged in a partial ACL tear. The ligament is still partially intact and functional. The severity of a partial tear can vary, and it can sometimes be challenging to distinguish it from a complete tear based solely on clinical examination.

Magnetic Resonance Imaging (MRI) is often used to determine the extent of the tear. Treatment options for a partial ACL tear may include rehabilitation and physical therapy to strengthen the surrounding muscles and provide stability, but surgical intervention may be recommended in some cases.

Complete ACL Tear

A complete ACL tear is a more severe injury where the ligament is fully severed or torn into two separate pieces. This type of injury significantly impairs the stability of the knee joint. A complete ACL tear is typically more apparent in clinical examinations, as it often results in greater joint instability and a positive Lachman or Drawer test.

Surgical reconstruction of the ACL is often recommended for individuals with a complete tear, especially those who lead an active lifestyle or participate in sports that require pivoting and cutting movements.

Treatment Options for ACL

The treatment for an anterior cruciate ligament (ACL) injury can vary depending on the severity of the injury, the individual’s activity level, and overall health. Treatment options for ACL injuries generally fall into non-surgical (conservative) and surgical. Here’s an overview of both approaches:

Non-Surgical (Conservative) Treatment

1. Rest and Immobilization – Immediately after the injury, it’s important to rest the knee and protect it from further damage. In some cases, immobilisation with a knee brace or a hinged knee immobiliser may be necessary.

2. Physical Therapy – Physical therapy is a key component of non-surgical treatment. It focuses on strengthening the muscles around the knee, improving stability, and regaining range of motion. A physical therapist will design a personalised exercise program.

3. Use of Assistive Devices – Crutches may be used initially to help reduce weight on the injured leg and promote healing.

4. Bracing – A knee brace may be prescribed to provide support and stability during physical activity.

5. Activity Modification – It may be necessary to temporarily modify or avoid certain activities, especially high-impact or pivoting sports, to prevent further damage to the knee.

6. Anti-Inflammatory Medications – Non-steroidal anti-inflammatory drugs (NSAIDs) can help manage pain and reduce inflammation. Always follow your healthcare specialist’s recommendations regarding their use.

Surgical Treatment (ACL Reconstruction)

Surgical intervention is often recommended for individuals with a complete ACL tear, especially those who wish to return to activities that require knee stability and agility. ACL reconstruction surgery involves the following steps:

1. Graft Selection – The surgeon will choose a graft (tissue) to replace the torn ACL. Common graft options include using a portion of the patellar tendon, hamstring tendons, or donor grafts (allograft).

2. Arthroscopy – The surgeon will use minimally invasive arthroscopic techniques to insert small instruments and a camera into the knee joint to visualise and assess the extent of the injury.

3. Graft Insertion – The chosen graft is inserted into the knee joint through small incisions and secured in place using screws or other fixation devices.

4. Rehabilitation – After surgery, a comprehensive rehabilitation program is essential. Physical therapy will help restore strength, range of motion, and knee stability.

5. Return to Activity – Full recovery and return to high-impact activities can take several months. A gradual return to sports or activities is recommended under the guidance of a physical therapist or sports medicine specialist.

Anterior cruciate ligament (ACL) injuries can significantly impact one’s quality of life, particularly for individuals engaged in active or sports-related activities. The decision to pursue surgical or non-surgical treatment is made on a case-by-case basis.

Regardless of the chosen treatment path, rehabilitation and physical therapy play a vital role in recovery. A committed effort to regain strength, flexibility, and stability is key to restoring the knee’s functionality.

Consultation with an orthopaedic specialist is essential for accurate diagnosis and tailored treatment plans. With proper care and dedication to rehabilitation, individuals can achieve the best possible outcome and return to an active, pain-free life. Remember, recovery is a journey, and each step brings you closer to a healthier and more agile future.

Dr Lee is an experienced orthopaedic surgeon who specializes in

Anterior Cruciate Ligament Tears

He will assess your condition and advise the best form of treatment for your condition. With proper treatment, patients can look forward to a full and quick recovery without complications.

Dr Lee Eu Jin

CONSULTANT ORTHOPAEDIC SURGEON
JOINT REPLACEMENT SPECIALIST AND SPORTS SURGEON

MBBS (London), MRCS (Edin),
M.Med (Orth), FRCS (Orth & Trauma)

Dr Lee Eu Jin is a Consultant Orthopaedic Surgeon with a subspecialty interest in hip and knee surgery.