Cruciate Ligament Tear

Cruciate Ligament Tear (CLT)

Acronyms Medical

A cruciate ligament tear is also referred to in medicine as a cruciate ligament rupture. This is a crack that came about as a result of external force. A cruciate ligament rupture often occurs as a sports accident in football players or when skiing. Typical signs of a cruciate ligament rupture are pain in the knee, as well as visible bruising and swelling.

What is a cruciate ligament tear?

Schematic representation of the healthy cruciate ligaments and the different forms of cruciate ligament tears. See AbbreviationFinder for abbreviations related to Cruciate Ligament Tear.

A cruciate ligament rupture usually affects both cruciate ligaments, as they work almost like Siamese twins in the knee: the cruciate ligaments lie inside the knee between the joint bones, crossed over one another. There, on the one hand, they stabilize the knee against the dreaded cruciate ligament tear, and on the other hand, they ensure lateral three-dimensional mobility, which is important for sitting, walking and standing. In addition to the cruciate ligaments, the outside and the inside ligament on the knee are just as important, because without this fixation, the knee would fall out of its forward-facing plane, especially if the cruciate ligament ruptures, and the affected person would no longer be able to move.

The cruciate ligaments themselves consist of collagen muscle fibers and are cushioned by a mucous membrane sac, the synovial sac, towards the joint bone. They can also be reinforced by other ligaments, such as the meniscofemoral ligament and the Humphry ligament, but not everyone has these to the same extent. The cruciate ligaments are 18.5 to 33.5 mm long and usually made up of three fiber bundles, the anterior, posterior and medial pons.

Together with the knee ligaments on the outside and inside and the connection to the front meniscus ligament, they form the bridge between the thigh and lower leg. The combination of ligaments at the knee prevents forward overextension of the tibia and backward overextension. With a healthy structure, the cruciate ligaments optimally regulate the movement of the knee on all axes and the symmetrical alignment of the upper and lower leg.


Unfortunately, a cruciate ligament rupture is relatively common, although the cruciate ligaments are particularly protected against heavy loads due to the crossed position. A torn ligament usually only occurs when the ligaments are extremely overstretched in one direction. The cruciate ligaments are unlikely to tear under normal physical exertion, unless someone moves their knee in a dangling motion with considerable force. This usually only happens in accidents and when playing sports.

The cruciate ligament rupture is a typical athlete ‘s injury because it occurs most frequently due to the high stress on the knees during soccer and skiing. If the soccer ball is kicked from the side with force, so that a rotation occurs during the forward movement, this can lead to overstretching of the cruciate ligaments, which leads to a cruciate ligament rupture under load or if the other foot also slips on the lawn. In the event of a cruciate ligament tear in the anterior cruciate ligament, the rolling mechanism of the femoral head is severely disrupted. This causes damage to the meniscusand wear and tear on the cartilage in the knee joint. In the flexed position of the knee, the lateral knee ligaments are relaxed, which is why most accidents with cruciate ligament tears occur in this position, since the full force of the movement is transmitted unhindered to the inner ligaments.

Slalom skiing, starting in a bent position like tobogganing or ice hockey can be triggers. Prolonging the knee too far can tear the anterior cruciate ligament, while a blow to the tibial plateau can damage the posterior cruciate ligament. If both cruciate ligaments tear, which in most cases occurs when the movement is violent, the rotation of the lower leg backwards and inwards is no longer limited. The stability of the cruciate ligaments is a prerequisite for the health of the knee joint.

Destroyed cruciate ligaments also endanger the meniscus in its healthy function. If the ligaments are taut, they can absorb the force of an unexpected hit like in soccer and pass it on to the muscles. The risk of an accident is significantly greater when the ligaments are slack, because jerky stretching increases the risk of small tears in the fibers or complete tearing of the ligaments.

Symptoms, Ailments & Signs

A cruciate ligament tear can be clearly felt. A snapping or cracking sound can be heard at the moment the ligament breaks. After that, the affected knee swells and pain sets in. The pain is described by those affected as dull to stabbing, with pain peaks occurring again and again, during which the stinging increases sharply.

Along with the pain, bruising develops in the joint. The hematoma usually follows quickly and can spread to the entire joint over time. The bruise can appear immediately after the cruciate ligament tear, but sometimes it occurs with a delay or not at all. The ligament injury causes instability in the knee, which in some cases results in additional symptoms and discomfort.

The feeling that thighs and lower legs are wedged together is typical. In addition, there is a pronounced unsteadiness in gait, often associated with a spontaneous buckling in the joint. After a few days there is a loss of performance and stretching and bending inhibition or pseudo-blockade in the knee joint. Depending on which cruciate ligament is affected, the type and severity of the symptoms can vary greatly. In isolated cases, a cruciate ligament rupture occurs without further injuries.


Patients with cruciate ligament tears can often experience complications and disorders after an operation. If a cruciate ligament rupture is not treated at all, instability is to be expected, since a healthy cruciate ligament would ensure good fixation of the thigh and lower leg in the knee joint. The instability leads to increased mobility of the knee.

This can subsequently lead to possible damage to the knee, possible wear and tear or other consequential damage to the body. Since a cruciate ligament rupture does not heal spontaneously, professional treatment in the form of an operation is recommended in any case. If the result after an operation is not satisfactory, the procedure often has to be repeated.

The specialists divide the possible disorders after an operation into early and late complications. Complications that occur early and therefore immediately after the operation include wound healing disorders, a bacterial infection of the knee joint or thrombosis in the leg. Early complications are less likely to occur than late complications.

Late complications include residual knee joint instability or limitation of movement. When movement is restricted, the knee joint is often unable to fully extend and bend. A reaction to intolerance with bone expansion is also possible.

When should you go to the doctor?

Anyone who has suffered a cruciate ligament tear should see a doctor as soon as possible. A cruciate ligament tear is an injury that definitely needs medical and drug treatment. Otherwise a full recovery cannot be guaranteed. The cruciate ligaments ensure stability and mobility inside the knee, so that a tear in the cruciate ligaments severely restricts and impedes the entire movement process. Affected people will have severe pain even when they are at rest, so that a trip to the doctor is essential. Anyone who completely foregoes medical treatment must expect considerable complications.

Even irreparable consequential damage can occur, since a healthy cruciate ligament ensures the overall stability of the knee. A full stretching and bending ability of the knee can also no longer be guaranteed if the visit to the doctor does not take place. Therefore, the following applies: A cruciate ligament tear should always be treated medically, with medication and with surgery, otherwise serious consequential damage can occur that can no longer be healed.

Treatment & Therapy

A cruciate ligament rupture, ie the injury or severing of one or both cruciate ligaments in the knee joint, is diagnosed by the doctor by carefully examining the movement of the knee. The knee may be double swollen. The doctor, preferably a sports doctor or orthopaedist, must proceed with caution. If the cruciate ligament is torn as a result of a violent fall while playing sports and the knee joint is twisted, other ligaments are often also affected.

The patient is in extreme pain from the bruising normally associated with the tear. If blood and light-colored liquid appear when the doctor punctures the knee, this indicates a rupture of the cruciate ligaments. If it is also determined during the anamnesis that the lower leg and thigh can be moved in a drawer-like manner against one another, this is a sure indication of a cruciate ligament rupture. However, the extent of knee injuries with a cruciate ligament rupture can only be specified by a knee mirror. During the endoscopy, the doctor will not only determine the injury, but also immediately sew a cruciate ligament to reconnect the severed fibers.

When the cruciate ligaments are so fibrous and torn unevenly that they cannot be repaired with sutures, the surgeon replaces them from a strip of fibers harvested from the thigh muscles. In older people, the doctor prefers not to operate and immobilizes the knee with a knee brace so that the fibers can heal by themselves.

Outlook & Forecast

In most cases, the chances of healing from a cruciate ligament tear are very good. The different healing times of conservative and surgical treatment must be taken into account. In terms of conservative therapy, after a short period of immobilisation, the patient must immediately put weight on his knee again in the form of a detailed muscle building program. If, on the other hand, a cruciate ligament tear has been surgically corrected, the patient may only fully use his knee again after about three to four months.

Serious complications, such as bleeding of the nerves and vessels, joint infections or thrombosis should not occur. If physiotherapeutic therapy is started early, the risk of arthrosis is significantly reduced. This counteracts joint wear. In order to increase the chances of recovery, it is important to train the joint sufficiently and, above all, regularly during therapy. After that, full mobility and strength can be expected again.

If the person concerned wants to be active again at the highest level of sport after the healing process, he should give this plan at least six months to counteract another cruciate ligament tear. In all cases, it is advisable to treat a cruciate ligament tear as quickly as possible. If no treatment measures are initiated, the affected person can expect reduced performance and wear and tear of the knee joint.


The same exercises that the orthopedist recommends for knee and muscle training to strengthen ligaments are also used to reactivate the knee after a cruciate ligament rupture has healed. Knee exercises to strengthen all ligaments are also the best prevention for active athletes who practice sports that put strain on the knee joints. Since a cruciate ligament rupture is almost never seen in ballet dancers, whose ligaments and joints are exposed to extreme stretching and stress, some barre training exercises can be copied there for knee strengthening.

All up and down movements, knee bend positions, and stair climbing should be done symmetrically from the joints and slowly to allow the muscles to accompany the ligament positions. The Alexander technique and a complementary medical manual treatment method (e.g. Rolfing) are body therapies that can be used to strengthen ligaments in general. Athletes who make full use of their pelvic floor muscles and use their spine in an optimal alignment to gravity are less prone to accidents and non-anatomical movements.


A cruciate ligament tear is a serious injury that can have far-reaching consequential damage. Careful follow-up care is necessary to reduce the risk of osteoarthritis and other complaints. Patients with cruciate ligament tears are initially required to attend all medical check-up appointments that are offered during the first few weeks and months.

In addition, those affected also visit the doctor if new symptoms arise or the healing process is delayed. Physical rest is an essential part of aftercare for a cruciate ligament tear. The knee in particular must not be subjected to unnecessary stress, either during sports or at work.

Nevertheless, muscles and ligaments in the knee area have to be trained, so that individually tailored exercise programs are necessary from the physiotherapist. Even if the symptoms of the cruciate ligament rupture have subsided after a few months after conservative or surgical therapy, caution is advised.

In principle, patients with cruciate ligament tears should have regular check-ups throughout their lives to check the condition of the ligaments and especially the knee joint. Because a cruciate ligament rupture promotes the development of arthrosis, which often only becomes apparent decades after the accident. The doctor can therefore prescribe special sports, health shoes and insoles that prevent arthrosis and minimize the long-term consequences of a cruciate ligament rupture as much as possible.

You can do that yourself

In the event of a cruciate ligament tear, the first thing to do is to protect the injury and immobilize it. The affected leg is best cooled immediately with ice packs or cold packs and stabilized with a compress to counteract the swelling and to relieve pain. A doctor should then be consulted immediately.

Immediately after the operation, the injured cruciate ligament must continue to be cooled and protected – for at least a week. The stretch is also important. The joint is moved passively and – if possible – fully stretched out. You can then slowly start training again. In cooperation with the physiotherapist, you can start with physiotherapy and gentle sports such as swimming. In the first few weeks, the focus should be on slowly improving the load-bearing capacity of the cruciate ligament through individual exercises. Slight squats and training equipment such as the leg press or a bicycle ergometer are ideal for this. In addition to these physiotherapeutic measures, the injury must be checked regularly.

Ideally, the cruciate ligament tear will be completely healed after six to eight weeks and you can switch back to your original training. In severe cases – such as when the cruciate ligament had to be replaced – the strength and coordination exercises should be continued permanently.

Cruciate Ligament Tear