Ligament rupture
anterior cruciate ligament (ACL)

Physiological Function of the Anterior Cruciate Ligament (ACL)

Knee Stability
– The ACL contributes to anterior stability of the knee by preventing the tibia from sliding forward relative to the femur.
– It also limits excessive rotation of the tibia relative to the femur, in particular by stabilizing the knee during pivoting movements and changes of direction.

Movement Control
– The ACL helps control flexion and extension movements of the knee by maintaining correct alignment between the femur and tibia.
– It is particularly stressed during sporting activities that involve rapid changes of direction, jumps or landings.

In short, the anterior cruciate ligament is a crucial part of the knee's anatomy, providing stability and controlling movement. Its rupture can have significant consequences on knee function and health, often requiring medical intervention for optimal recovery.

What are the signs of severity of ACL rupture and the mechanisms of this trauma?

An ACL tear usually occurs during sudden movements or twists of the knee, often during pivoting sports such as football, basketball or skiing.
This injury can lead to knee instability, decreased function, and potentially other associated injuries such as meniscal tears or damage to articular cartilage.

Signs of severity of an anterior cruciate ligament (ACL) tear can vary depending on the severity of the injury and associated injuries.

Signs of ACL Tear Severity

Acute Knee Pain:
– Severe pain occurring immediately after a sudden movement or trauma to the knee may indicate an ACL tear.

“Popping” or “Cracking” Sensation:
– Many patients describe feeling or hearing a “pop” or “crack” at the time of injury, which may indicate an ACL tear.

Knee Instability:
– A feeling of laxity or instability in the knee, especially when walking, going up or down stairs, or during pivoting movements, is common in cases of ACL rupture.
– The knee may appear to “give way” or “give” under the weight of the body.
–
Rapid Swelling:
– Significant swelling of the knee within hours of the injury can be a sign of severity, often accompanied by increased pain and tenderness.

Limitation of Mobility and Flexion:
– Difficulty fully bending or extending the knee may indicate a serious ACL injury, due to the associated pain and instability.

Mechanisms and causes of ACL rupture

Pivoting Movement:
– Most ACL tears occur during pivoting movements of the knee, often during sports such as football, basketball, or skiing.
– The knee is twisted or turned abruptly while under load, putting excessive stress on the ligament.

Knee Hyperextension:
– Forced hyperextension of the knee, often during awkward falls or jumps, can lead to an ACL tear.

Awkward Landing:
– An awkward landing after a jump, with the knee bending inward or outward, can cause an ACL injury.

Sudden Stop:
– A sudden, violent stop, such as during rapid deceleration or a change in direction, can also stress the ACL beyond its capacity to hold.

An anterior cruciate ligament tear is a serious injury that can have a significant impact on knee function and stability.
Signs of severity, such as severe pain, knee instability, and significant swelling, require immediate medical evaluation for an accurate diagnosis and appropriate treatment plan.

Non-Surgical Treatments

Rehabilitation and Muscle Strengthening
– Physical rehabilitation is often recommended to strengthen the muscles surrounding the knee, particularly the quadriceps and hamstrings, to stabilize the joint and partially compensate for the missing ACL.
– The exercises also aim to improve knee mobility, balance and proprioception.

Support Splint
– The use of a knee brace may be recommended to provide additional support and help prevent excessive movement, especially when returning to daily activities or sports.
–
Pain and Inflammation Management
– Anti-inflammatory medications and pain relievers may be prescribed to relieve pain and reduce inflammation in the knee.

Arthroscopic ACL ligament reconstruction

Cruciate ligament reconstruction is a surgical procedure to reconstruct a torn cruciate ligament in the knee.
This procedure is often performed when the anterior cruciate ligament (ACL) is damaged, although the posterior cruciate ligament (PCL) can also be repaired in this manner.
Here is a detailed explanation of what an ACL reconstruction involves:

Purpose of ACL Ligamentoplasty
The goal of ligament reconstruction is to restore stability to the knee by replacing the torn ligament with a graft.
This allows the patient to regain normal knee function, resume daily activities and, often, sports activities.

Indications for Ligamentoplasty
– Complete ACL rupture with significant knee instability.
– Failure of conservative (non-surgical) treatment to relieve symptoms.
– Young, active patients wishing to resume sports or activities requiring knee stability.
– Presence of associated meniscal or cartilaginous lesions which require surgical intervention.
– Types of Grafts Used
– Autograft: Harvesting a tendon from the patient to reconstruct the ACL. Common options include:

– Patellar tendon.

– Hamstring tendons (semitendinosus and gracilis).

– Quadriceps tendon.

– Allograft: Use of a tendon from a human donor.

– This is an option for patients who prefer to avoid having tendon harvested from their own body.

Steps of the Procedure
Patient Preparation:

The patient is placed under general or spinal anesthesia.
The knee is cleaned and prepared for surgery.
Arthroscopic Access:

Small incisions are made around the knee to insert an arthroscope (camera) and surgical instruments.

Assessment and Preparation:

The surgeon evaluates the inside of the joint to confirm the ACL tear and identify other injuries.
The damaged ACL remnants are removed, and the insertion sites on the femur and tibia are prepared.
Graft collection:

If an autograft is used, the graft is harvested from the selected tendon.
If an allograft is used, the graft is prepared from donor tissue.
Creation of Bone Tunnels:

Tunnels are drilled into the femur and tibia to allow the passage and fixation of the graft.
Insertion and Fixation of the Graft:

The graft is passed through the bone tunnels and secured using fixation devices such as screws, staples or buttons.
Stability Check:

The surgeon checks the tension and position of the graft to ensure that it is properly secured and that the knee is stable.
Closing the Incisions:

The incisions are closed with sutures or adhesive bandages.
Postoperative rehabilitation

Initial Phase:

Rest and protect the knee with the use of crutches and a splint.
Managing pain and swelling with medication, ice, and elevation.

Rehabilitation:

Physiotherapy program to restore mobility, strengthen muscles and improve proprioception.
Progressive exercises to increase flexibility and strength.
Gradual Return to Activities:

Rehabilitation continues over several months, with a gradual return to normal and sporting activities under the supervision of the physiotherapist.
Expected Results
Restoration of knee stability.
Improved function and mobility.
Reduction of pain and inflammation.
Resumption of sports activities for most patients.

ACL reconstruction is an effective surgical procedure to treat ACL tears. With proper rehabilitation, most patients can expect to regain good knee stability and function, allowing them to return to their daily activities and sports.

Direct ACL repair

Direct anterior cruciate ligament (ACL) repair is a surgical technique that aims to repair the damaged ligament rather than replacing it with a graft, as is done in ligament reconstruction.
This approach is less common than ACL reconstruction, but may be appropriate in some specific cases.

Decision Factors

Several factors must be considered when deciding on the most appropriate treatment for an ACL tear, including:

– The patient’s age and activity level.
– Knee stability and laxity.
– The presence of associated lesions, such as meniscal tears or cartilage lesions.
The patient's functional goals, including resuming sports or physical activities.

Treatment for an ACL tear can vary based on several factors, and is typically individualized for each patient. Treatment options range from rehabilitation and muscle strengthening to surgical procedures such as ACL reconstruction, depending on the patient's needs and goals, as well as the severity of the injury. A thorough evaluation by an orthopedic surgeon is essential to determine the optimal treatment plan.