What Is an MCL Tear?

(I) Causes of Onset

Swelling bruising on the inside of the knee joint with local severe pain

In most cases, the knee joint suffered a sudden valgus or rotational external force. After the ligament was broken, the medial knee joint was generally swollen, and local pain was severe, subcutaneous congestion, and bruising.

Affected area

Limbs

Related diseases

Swelling of knee osteoarthritis

Related symptoms

Joint swelling, tension, severe pain, cyst, fatigue, ligament rupture, edema, weak knee injury, swelling and pain, knee swelling, pain after knee, swelling, pain, restricted movement

Affiliated Department

General surgery

Related inspections

CT examination of bones, joints and soft tissues

(I) Causes of Onset

When the knee joint is in a slightly flexed position, gravity or severe injury to the outside of the joint can cause damage to the ligament.

(Two) pathogenesis

Among the knee ligament injuries, the medial collateral ligament injury is the most common. The injury mostly occurs when the knee joint is flexed slightly, and the calf suddenly abducts. Such as football, basketball or gravity hit the outside of the knee joint can cause damage to the medial collateral ligament. Lesser external forces can cause ligament strain, or some fibers can break. Severe external force can occur complete rupture or anterior cruciate ligament rupture or meniscal rupture.

In most cases, the knee joint suffered a sudden valgus or rotational external force. After the ligament was broken, the medial knee joint was generally swollen, and local pain was severe, subcutaneous congestion, and bruising. Hemorrhage in the joints is the main cause of pain. Patients often walk with their toes, and when their knees are abducted, there is significant pain at the rupture of the ligament. Due to reflex muscle tension, joint movement is limited, resistance and pain during passive straightening. If the hemorrhage is removed, the joint activity can be restored. Positive signs were mainly local tenderness in the medial collateral ligament.

The medial collateral ligament can be divided into three types: partial rupture, complete rupture, rupture of meniscus or cruciate ligament.

Partial rupture can be limited to the superficial or deep ligament, the upper or lower ligament attachment, posterior superior oblique or posterior inferior oblique, and occasional ligament rupture, local bleeding and ossification affect joint flexion and extension.

A complete rupture may be a superficial avulsion from the tibial attachment, a deep avulsion from the femoral attachment, or the other way around. The broken end of the ruptured ligament can penetrate into the joint space, disrupting the movement of the joint.

Because the ligaments are elastic and difficult to break, superficial ligament ruptures are often associated with avulsion fractures of the femoral condyle, but the ligament is relatively broad in the tibial condyle attachment, so avulsion fractures are less likely to occur. When the central part of the deep ligament is broken, the edge of the inner meniscus is often ruptured. The deep and shallow two layers are broken at the central part of the ligament. The cruciate ligament can also be broken at the same time. The stability of the knee joint will be severely damaged.

The diagnosis is not difficult. A history of trauma with calf abduction injury is the main basis for the diagnosis. The clinical manifestations are swelling, bleeding, bruising, and tenderness near the ligaments. If it is completely broken, you can feel the loss of contact at the collateral ligament injury. The knee test is the most important test to determine the extent of the injury. The examiner holds the ankle joint in one hand and the other hand rests on the outside of the patient's knee joint. The knee joint should be in the straight or flexed position of 30deg; Pain in the medial collateral ligament indicates that the ligament has been damaged. If there is looseness and joint opening at the same time, the ligament is broken. To avoid pain and reflex protection of the muscle, it is best to check under anesthesia or after the pain point is closed. The patient must be instructed to relax the muscles during the test to avoid false negatives.

Due to the limited joint movement caused by the rupture of the ligament, the joint movement can be restored after the procaine local ligament is closed. However, if the interlocking of the joint caused by the meniscus rupture, although the joint hemorrhage is drawn or the local procaine is closed, the interlocking sometimes cannot be relieved. The structure is mainly the superficial layer of MCL of the knee joint, and those who are subjected to stress are most vulnerable to damage. The order of stress is the order of damage. In addition, if the MCL injury is left untreated for a long period of time, other ligaments will loosen and rotation instability will occur.

It should be differentiated from the following symptoms:

1. Swelling of the knee joint Swelling of the knee joint is synovitis of the knee joint. The knee joint synovium is the widest and most complex of the human joints, and it also forms the largest synovial cavity. Because the knee joint is heavy, it has the most movement and is most vulnerable to injury.

2. Knee bruise, swelling and pain Knee pain: The tip of the iliac crest begins to be sore and uncomfortable, and persistent dull pain appears later. The law is that the pain increases at the beginning of the activity, and the pain decreases after the activity is started. In daily life and work (such as going up and down stairs, squatting upright, walking with weights, kicking the ball, etc.), when doing quadriceps contraction, There will be pain in the tip of the palate. In severe cases, pain in the tip of the palate also occurs during normal walking. The patient felt that his knees were weak and weak, and he was easy to walk with fatigue. As a result, his shoulders could not be lifted, his hands could not be lifted, and he could not walk with heavy loads. There is obvious tenderness at the tip of the palate. When you touch it, you can feel the swelling and blunt thickness of the patellar tendon attachment. Some patients can feel the tip of a proliferating bone spur. Pain occurred at the tip of the heel when performing knee extension resistance test and half squat test. Regardless of chronic or acute diaphragmatic injury, the main manifestations are pain in the popliteal fossa when squatting or getting up, or when going upstairs or climbing, and its nature can be intermittent or continuous. Most chronic injuries are manifested as Dull pain, acute injury is severe or severe tear-like pain or drag-like pain.

3. Swelling and pain behind the knee, restricted movement. Popliteal cysts are more common in middle-aged patients and have the highest incidence. There are more men than women, which results in mechanical knee extension and knee flexion limitation. The pain is lighter and the tension is obvious. Patients often complain of swelling in the popliteal area with pain behind the knee. Occasionally, cysts can oppress venous return and cause calf edema. When the cyst grows to a certain extent, the flexion and extension of the knee joint is limited.

In most cases, the knee joint suffered a sudden valgus or rotational external force. After the ligament was broken, the medial knee joint was generally swollen, and local pain was severe, subcutaneous congestion, and bruising. Hemorrhage in the joints is the main cause of pain. Patients often walk with their toes, and when their knees are abducted, there is significant pain at the rupture of the ligament. Due to reflex muscle tension, joint movement is limited, resistance and pain during passive straightening. If the hemorrhage is removed, the joint activity can be restored. Positive signs were mainly local tenderness in the medial collateral ligament.

The medial collateral ligament can be divided into three types: partial rupture, complete rupture, rupture of meniscus or cruciate ligament.

Partial rupture can be limited to the superficial or deep ligament, the upper or lower ligament attachment, posterior superior oblique or posterior inferior oblique, and occasional ligament rupture, local bleeding and ossification will affect joint flexion and extension.

A complete rupture may be a superficial avulsion from the tibial attachment, a deep avulsion from the femoral attachment, or the other way around. The broken end of the ruptured ligament can penetrate into the joint space, disrupting the movement of the joint. Because the ligaments are elastic and difficult to break, superficial ligament ruptures are often associated with avulsion fractures of the femoral condyle, but the ligament is relatively broad in the tibial condyle attachment, so avulsion fractures are less likely to occur. When the central part of the deep ligament is broken, the edge of the inner meniscus is often ruptured. The deep and shallow two layers are broken at the central part of the ligament. The cruciate ligament can also be broken at the same time. The stability of the knee joint will be severely damaged.

The diagnosis is not difficult. A history of trauma with calf abduction injury is the main basis for the diagnosis. The clinical manifestations are swelling, bleeding, bruising, and tenderness near the ligaments. If it is completely broken, you can feel the loss of contact at the collateral ligament injury. The knee test is the most important test to determine the extent of the injury. The examiner holds the ankle joint in one hand and the other hand rests on the outside of the patient's knee joint. The knee joint should be in the straight or flexed position of 30deg; Pain in the medial collateral ligament indicates that the ligament has been damaged. If there is looseness and joint opening at the same time, the ligament is broken. To avoid pain and reflex protection of the muscle, it is best to check under anesthesia or after the pain point is closed. The patient must be instructed to relax the muscles during the test to avoid false negatives.

Due to the limited joint movement caused by the rupture of the ligament, the joint movement can be restored after the procaine local ligament is closed. However, if the interlocking of the joint caused by the meniscus rupture, although the joint hemorrhage is drawn or the local procaine is closed, the interlocking sometimes cannot be relieved. The structure is mainly the superficial layer of MCL of the knee joint, and those who are subjected to stress are most vulnerable to damage. The order of stress is the order of damage. In addition, if the MCL injury is left untreated for a long period of time, other ligaments will loosen and rotation instability will occur.

(A) treatment

1. Fresh medial collateral ligament injury

(1) Partial rupture (degree, degree sprain): Put the knee at 30deg; 45deg; flexion position, fix it with the knee joint back and forth plaster support, exercise the quadriceps, and walk under the plaster with about 1 week Or, it is allowed to use a full range of protective braces. You can also use a tubular brace, a controlled stent for 4 to 6 weeks, and then practice knee extension and flexion activities.

(2) Complete rupture ( degree sprain): Simple MCL degree injury can be successfully treated by non-surgical methods. In the Indelicato study, the efficacy of using plaster, cast braces, or commercial activity-limiting stents was comparable to that of surgically repairing MCL. Reider et al. Reported that non-surgical treatment of 35 athletes with pure degree III MCL injury was similar to the results of previous investigators. It is generally believed that the same severe tear occurs when the MCL distally heals less well than the proximal one. The distal ligament can be pulled proximally and occasionally shifted to the superficial point of the goose foot. It cannot be automatically reset. .

Surgery: Under epidural anesthesia and balloon tourniquet, make an S-shaped incision in the knee, starting from 1.5 to 2.0 cm above the femoral condyle, and stop at the anterior side of the tibial condyle. Pay attention to protect the saphenous vein and saphenous nerve. , Cut deep fascia to expose MCL. Abducting the knee joint to determine the plane of the ligament rupture, hematoma or congestion spots can be found in the ligament. First flip the torn superficial layer upwards, then check the deep layer. If the ligament is also broken, cut the switch capsule to detect the meniscus and ACL rupture on the inside of the zygomatic ligament and the joint of the quadriceps tendon. For patients with simple avulsion of the MCL attachment or small avulsion fractures, a shallow groove can be cut in the bone at the ligament avulsion, and a hole is drilled at the anterior and posterior edges. The thick ligament is used to fix and suture the ligament broken end. Larger avulsion fractures can be fixed with U-shaped nails, nail plates or screws. Regardless of the superficial or deep ligament rupture, use the opposite end or overlap suture. However, after all the injuries have been repaired, appropriate strengthening surgery can be selected according to the situation, such as suture the hemi-membrane tendon to the posterior medial angle to strengthen the oblique ligament, and the hemi-membrane tendon to strengthen the MCL. Medial muscle moves forward.

Knee flexion was 30deg; ~ 45deg; postoperative plaster fixation for 4-6 weeks.

Patients with MCL rupture and ACL rupture had poor conservative treatment. The ACL must be reconstructed and repaired (for details, see Anterior Cruciate Ligament Rupture). If there is no rotation instability, MCL may not be repaired. Shelbourne reported 368 patients with combined ACL and MCL injuries. MCL injury was treated nonsurgically and ACL was reconstructed. His conclusion is that this treatment scheme can restore excellent stability. Sandberg et al. Compared a surgical and non-surgical treatment of MCL injury alone and ACL and MCL injury in a prospective, randomized study. Surgical treatment of torn MCL is not beneficial in situations, and can lead to joint stiffness. Indelicato first reconstructs the ACL; if the knee joint still shows instability in the fully extended or slightly flexed position, the MCL should be repaired.

For patients with MCL combined with medial meniscus injury, if the median meniscus edge is slightly torn, the rupture can be sutured to prevent the edge of the torn meniscus from folding back into the joint cavity and causing knee interlocking. If the rupture is severe, the medial meniscus must be partially or completely removed and sutured to repair the MCL.

2. Old MCL rupture Old MCL injury, especially when combined with ACL rupture, the stability of the knee joint is damaged, and other ligaments relax after chronic stretch, resulting in lateral instability and anterior medial rotation instability of the knee joint. Anterior and lateral instability are produced. The surgical repair methods are summarized into two categories:

(1) Static repair method: The soft tissue near the knee joint is used to repair the damaged ligaments and defects. Common materials are semitendinosus tendon, gracilis tendon or broad fascia to restore the tension of MCL. This method has satisfactory results in the near future, but over time, the elasticity of the reconstructed ligament decreases and gradually relaxes, so the long-term effect is often not ideal.

MCL repair method of gracilis tendon: S-shaped incision of the medial knee to expose the gracilis muscle, cut the tendon of the gracilis muscle in the femoral condyle equivalent to the plane where the MCL of the knee is attached, and bury the distal end of the severed tendon in the stump. Under the bone flap lifted from the upper end of the femoral condylar ligament, bend the knee 20deg; tighten and suture to fix, then sew the tendon on the MCL. The proximal end of the severed gracilis tendon is sutured to the sartorius muscle.

Knee MCL displacement and suture method: It is suitable for patients with loose knee MCL. The method is to cut the upper starting point of knee MCL together with its attached cortex, shift it forward and upward, and tighten it with screws.

(2) Dynamic repair method: The normal tendon is displaced and the muscle tension is used to stabilize the knee joint. Common methods such as goose foot tendon displacement: suitable for knee joint MCL rupture combined with ACL injury, there is a positive front drawer test, when the knee joint is violently active, knee joint instability or soft leg phenomenon occurs.

Surgery method: Peel off 2/3 of the distal end of goose foot (thin joint of gracilis muscle, sartorius muscle and semitendinosus muscle at the anterior and medial end of tibia), peel it upwards, and sew on the inner edge of patellar tendon Below the tibial condyle to make it run horizontally to enhance its internal rotation, or separate the distal end of the sartorius muscle separately, and suture the quadriceps expansion with the patellar tendon, and then stop the remaining goose foot tendon to stop Cut off and reverse the suture as described above.

This surgery is a dynamic repair, and the postoperative symptoms can be significantly improved, which overcomes the shortcomings of poor long-term effects of pure static repair. However, the signs of MCL relaxation are still present during the examination, so the function should be improved when assessing the effect of the surgery. As the main basis.

Postoperative treatment: After the above-mentioned operations, the knee joint was fixed at 30 degrees flexion with a long leg anterior-posterior plaster cast. The fixation was performed for 4 weeks for those with fresh ligament injury and 6-8 weeks for reconstruction and repair of old ligament injury. Remove the plaster and practice knee movements.

(B) the prognosis is good.