Medial (MCL) and lateral (LCL) collateral ligament surgery

Knee joint function

The function of the knee is to enable movement, but also transferring the weight of the body to the feet during walking. The articular bodies in the knee area are a combination of the convex articular surface of the femur and the almost flat articular surface of the shin bone (tibia). In this way, the mobility of the knee is increased, but its stability is also significantly reduced. In order to increase the stability of the knee, the correct function of the knee stabilizers is of vast importance.

There are active and passive stabilizers. Active stabilizers are muscles that are among the strongest in the human body and at the same time they move the joint. Passive stabilizers are: ligaments, joint capsule and menisci. The most important ligaments of the knee are: internal (medial) and outer (lateral) collateral ligaments and anterior and posterior cruciate ligaments.

Medial collateral ligament (MCL)

The medial (internal) collateral ligament (MCL) is one of the 4 key ligaments responsible for knee stability. It is located on the inside of the knee where it connects the distal part of the femur (thigh bone) with the proximal tibia (shin bone). MCL is primarily responsible for preventing excessive movements of the knee inwards - when force is applied from outside of the knee. Such situations usually occur in sports such as contact sports, football, basketball, skiing, etc. MCL injury is one of the more common knee injuries (8% of all athletic knee injuries) and the most common knee ligament injury (40%), expected annual rate is 24 MCL injuries per 100,000 people.

Lateral collateral ligament (LCL)

The lateral (outer) collateral ligament (LCL) is also one of the 4 key ligaments responsible for knee stability. Unlike the MCL, it is located on the outside of the knee and connects the distal femur (thigh bone) with the proximal fibula. The function of the LCL is to resist the action of force from inside of the knee. The most common patients are athletes in certain sports (football, basketball, skiing, etc.), especially when knee rotation is present along with force. LCL injury, due to the complexity of structures of the outer part of the knee, rarely occurs as an isolated injury (<2% of knee injuries) usually in tennis players and gymnasts, but often occurs in combination with injuries to other knee structures.  

Knee anatomy

• Femur – thigh bone
• Patella – kneecap
• Tibia – shin bone
• Fibula – smaller bone of the lower leg
• Collateral ligaments – tough, elastic connective tissue that surrounds a joint to provide stability
• Cruciate ligaments - the anterior and posterior cruciate ligaments form the letter X and ensure rotational stability and prevent excessive displacements of the lower leg in relation to the upper leg.
• Menisci – curved cartilaginous parts in the joint that serve as shock absorbers that absorb the load, increase the contact of joint surfaces, etc.
• Muscles – serve to dynamically stabilize the joint

Injury mechanism of collateral ligaments

An acute injury to the medial collateral ligament (MCL) is usually caused by force applied to the outer part of the knee, especially during slight flexion and rotation of the lower leg. Analogously, an injury to the lateral collateral ligament (LCL) occurs during the action of a force that pushes the knee outward (action of force on the inner part of the knee), especially during hyperextension and rotation of the lower leg. Activities that lead to collateral ligament injuries, which are common in many sports, are:

• collision or direct blow to the knee area
• sudden changes in the direction of movement
• turning with the feet firmly attached to the ground
• abnormal landing
• sudden stop after sprinting

Such actions can lead to ligament injury, which can result in a complete rupture, a partial rupture, or a minor injury (strain) that does not lead to rupture of the ligaments. Also, in addition to collateral ligament injuries, other associated injuries are common, such as meniscal tears, cartilage damage, or injuries to other knee ligaments, such as anterior cruciate ligament rupture.

Symptoms of collateral ligament injury

Early signs:

• "snapping sound" at the moment of injury
• the knee "gave way" at the moment of the injury
• severe pain and inability to continue activities after the injury
• rapid swelling of the knee

Later signs:

• feeling of instability in the knee
• pain in the area of injury (medial or lateral)
• reduced range of motion
• inability to perform physical activity or work

Do you have any of the above mentioned complaints? Make an appointment for an examination with our experts.

What to do immediately after the injury?

Immediately after an injury, it is necessary to reduce pain and swelling in the knee using the R.I.C.E. model that can be performed at home:

• Rest – it is necessary to reduce the load on the knee
• Ice –it is necessary to cool the knee with ice packs every 2 hours for 20 minutes to reduce swelling
• Compression – it is necessary to wrap the knee with an elastic or other bandage
• Elevation – in the supine position, it is necessary to place pillows under the injured leg

When to see a physician?

In the event of trauma that has caused symptoms of injury, contact a doctor as soon as possible. Collateral ligaments are extremely important structures in the knee, with many functions, especially in people who want to play sports. It is important to ensure timely diagnosis and adequate therapy for each patient.

Risk factors for MCL and LCL injuries

• contact sports
• other sports such as football, basketball, skiing in which sudden changes of direction are frequent
• poor physical condition
• inadequate sports shoes and equipment
• surface changes (parquet, artificial grass, concrete, etc.)

Diagnostics

Preparation for examination

Before seeing an orthopedic surgeon, it is important for the patient to prepare answers to the following questions:

• When did the injury occur?
• What were you doing when the injury occurred?
• Did you hear a "popping" sound at the time of the injury?
• Is the knee swollen after the injury?
• Have you ever injured your knee before?
• Are your symptoms constant or do they appear occasionally?
• Has your knee ever locked up?
• Do you feel instability in your injured knee?

Orthopedic specialist examination

Diagnosing a rupture of the medial and lateral collateral ligament is made on the basis of knowledge and understanding of the biomechanical elements of the injury after a detailed description of mechanism of the injury and complaints. Information about the strength and direction of the force acting on the knee at the time of injury, the auditory sensation of popping, the inability to continue activities immediately after the injury, and the rapid swelling of the lateral parts of the knee are essential.

The clinical examination includes tests to assess the stability of the knee, tests to detect injuries to other structures such as the meniscus and cruciate ligaments, testing the range of motion and assessing the functionality of the entire knee. The orthopedic specialist will compare the function of the injured and healthy knee and make a decision on any additional diagnostic procedures.

Radiological diagnostics

In order to confirm the diagnosis of MCL and LCL injury in unclear cases, magnetic resonance imaging of the knee is performed. Magnetic resonance (MR) of the knee is a non-invasive examination to obtain quality data on the state of all structures of the knee joint. After determining the type and size of the injury, a decision on further treatment follows.

Treatment

Treatment must be personalized and adapted to the patient depending on the degree of damage. It is very important to establish a dialogue between the doctor and the patient. The most important factors that influence the decision are the age of the injured person, motivation, the level and type of physical activity that the person wants to engage in, the degree of knee instability and the condition of other knee structures. Treatment can be surgical or conservative.

Conservative treatment

Conservative, i.e. non-operative treatment consists of wearing a stabilizing orthosis and functional rehabilitation. While most injuries to the medial collateral ligament can be treated conservatively, a complete tear of the lateral collateral ligament usually requires surgical treatment.

Surgical treatment

Surgical intervention in case of rupture of the medial collateral ligament (MCL) is indicated in the presence of a multiligamentous injury and in the case of separation of the distal insertion of the ligament and its "transition" over nearby structures (tendons), which makes healing of the ligament and conservative treatment impossible.

Rupture of the lateral collateral ligament (LCL) is more often associated with other knee injuries such as an injury to the posterolateral corner (a group of structures in the posterior outer part of the knee) and generally requires surgical treatment.

The operation consists of the repair of the injured ligament or its reconstruction. The entire operation can be performed under spinal anesthesia, where the knee is approached from the medial or lateral side. During the operation, the operator repairs (sews) or removes the damaged ligament, while a tendon graft is used for reconstruction. Such a graft can be fixed with a completely resorbable material that slowly resorbs over time, i.e. melts inside the body after the graft has healed.

Risks of surgery 

As with any surgical procedure, there are risks with MCL/LCL reconstruction, such as bleeding or infection of the surgical wound. Other risks in the reconstruction of collateral ligaments can be:

• pain or stiffness of the knee
• poor healing of the graft ("new" ligament)
• rupture of the graft after returning to sports

Read how to prepare for surgery, and for more information make an appointment for an examination.

Postoperative rehabilitation

After the surgery, the patient is transferred to the department where physical therapy is started. Together with the physiotherapist, the patient learns how to walk on crutches and behave with the operated leg. The patient usually spends one night in the hospital after the procedure and is discharged from the hospital in the morning after dressing the surgical wounds and physical therapy. After leaving the hospital, it is advisable to continue rehabilitation in Center for physical medicine & rehabilitation. In order to ensure the fastest and highest quality recovery, it is important to adhere to the instructions on dressing the wound, diet, physical activity, etc. Before returning to normal physical activities, it is necessary to do several control examinations that will examine the current function of the knee joint.

Regardless of the medical condition, patient safety and satisfaction are top priorities at our Hospital, so contact us with confidence.