Ligament stretching (syn. ligament strain) of the knee is caused by a violent movement of the knee joint beyond the average extent and can affect both the inner and outer ligament.
It is one of the most common sports injuries and can be caused, for example, by a sudden rotational movement of the knee.
The transitions to a torn ligament or sprain are often fluid and therefore, cannot always be clearly distinguished from one another. However, the joint remains stable when the ligament is stretched, whereas it usually becomes unstable when torn. In order to achieve the quickest possible healing, the knee joint should be stabilized early on to protect the ligaments of the joint.
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The causes of ligament stretching are manifold. In most cases, extreme movements are the cause of ligament stretching in the knee. Due to the extreme movement, the natural range of motion of the ligaments is exceeded.
Since these situations often occur during sports, ligament stretching is the most common sports injury. The ligament stretches occur particularly frequently in sports with rapid changes of direction or contact with opponents.
These are particularly important:
However, ligament stretching can also be caused by violent overstretching from the outside, for example, if the opponent hits the knee joint from one side during sports.
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Symptoms of ligament stretching in the knee
The most common symptoms of ligament stretching are pain and swelling. The pain is particularly severe when the affected joint is moved. In contrast to a torn ligament, the swelling is often rather minor.
Since the affected ligament of the knee joint is not torn, the joint remains stable and resilient despite the pain. Walking and standing are still possible, but not always painless. Besides, when the ligament is stretched in the knee, there is usually no bruising (hematoma) because there is no injury to the blood vessels. The hematoma is, therefore, a further criterion for distinguishing it from a torn ligament.
Swelling with a ligament strain in the knee
Pain is the main symptom of ligament stretching in the knee. Also, knee swelling can also occur. However, both symptoms are less severe than, for example, a torn ligament.
The swelling is slight, sometimes even absent completely. This is because no or only little surrounding tissue is damaged when the ligament is stretched, and there is no tearing of blood vessels, as would be the case with a torn ligament. Bruises (hematomas) are therefore also absent when the ligament is stretched.
If there is swelling, it usually goes down quickly when the knee is cooled and protected.
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Diagnostics of ligament extension in the knee
Ligament stretching in the knee is very painful but usually has a harmless course.
The diagnosis usually results from the
- Description of the course of the accident
- Clinical examination
First, the doctor checks whether the joint is stable and whether there is pain from pressure from outside. Besides, the doctor determines whether a bruise has developed; this would be an indication of a torn ligament. If there is only a swelling of the joint, the knee joint is stable, and no bruise has developed, these are clear indications of the presence of a ligament tear.
The drawer test can be performed to check the stability of the knee joint clinically. This can determine whether the cruciate ligaments of the knee joint are intact. The pop-up test can be used to determine whether the inner or outer ligaments of the knee joint are injured. The knee joint is moved outwards and inwards against a pressure. Intact ligaments severely restrict this movement. If a ligament is torn, the knee joint can be moved outwards or inwards beyond the normal range of motion.
These clinical examinations can give the physician information about the extent of the injuries. However, exact diagnosis can be difficult, since the injury causes the muscles to be more strongly tensed in terms of their reflectors, which means that the ligaments cannot always be examined conclusively.
Ligament stretching in the knee can only be depicted by an ultrasound or an MRI of the knee. If the examiner is sure that the ligament is stretched, an ultrasound or MRI of the knee is not necessary. Since the transition to a partial tear of the ligament or even a torn ligament is fluid, it is often possible to obtain an image of the knee.
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Treatment of ligament extension in the knee
Sporting activity should be interrupted immediately to prevent further damage to the ligaments. On the one hand, cooling the knee joint relieves pain and prevents swelling of the joint. A pressure bandage (compression) also prevents increased swelling. Since the tissue is supplied with more blood through the reflectors after cooling, this would lead to increased swelling without compression. Elevating the knee joint also serves to counteract severe swelling of the knee joint.
As a matter of principle, ligament expansions should not be treated exclusively by immobilizing the joint and ligaments afterward. As a rule, it is important to stabilize the ligaments functionally. This will provide relief for the stretched ligaments, but the joint can still be moved within a limited range.
Stretch splints are used to treat stretched ligaments of the knee. Bandages or a plaster sleeve (“tutor”) can be used for this purpose. This extends from the thigh to the ankle joint and keeps the knee in an extended position. This prevents exaggerated movements of the knee joint and protects and relieves the damaged ligaments, while the movements of the other ligaments and muscles are not severely restricted.
Since the ligaments are intact and, therefore, stable after ligament extension, the knee joint can continue to be loaded. However, there should be no pain. If the ligaments are stretched very much, a rest period of 6 to 8 weeks may be necessary.
If there is no more pain afterward, the load can be slowly increased again. Since the ligaments were intact the whole time, the sport can be performed again without restrictions after healing.
The treatment of torn ligaments in the knee is individually tailored to each case.
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You can tap the knee to relieve it and reduce the pain. Tapes are elastic, self-adhesive rubber bands that are only stretchable in the longitudinal direction. They thus stabilize the knee and the stretched ligaments.
Tapes are stuck directly onto the skin. A physiotherapist or orthopedic surgeon can do this, or you can stick the tapes on yourself. Depending on the pattern of injury, there are different ways of sticking the tape on.
If you apply tape to the knee itself, make sure that the tape is applied around the kneecap and does not run over it. You start above the kneecap with the knee joint bent. Then the tape is pulled down slightly taut past the knee and stuck below the kneecap. The other side of the kneecap is then treated in the same way. For even more stability, you can put the ends of the tape on top of each other or apply a small cross tape.
Although tapes stabilize, in some cases they also relieve the pain of ligament stretching in the knee, but they are no substitute for a full-fledged therapy. So before using tapes, you should have a doctor check whether it is really just a knee ligament stretch and not a torn ligament or something similar.
If you still have pain despite the tapes, the question arises whether you should spare your leg for a while to let the stretching of the ligaments heal completely.
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Course of ligament extension in the knee
As a rule, simple ligament stretching is harmless and only associated with temporary impairments. As a rule, ligament stretching heals without complications if the affected knee joint is spared in case of pain. If sporting activities are interrupted for a few days, and there is no more pain, the knee joint can be fully loaded again afterward.
However, if the ligament of the knee joint is not sufficiently protected, instability of the knee joint can follow due to further injuries to the ligament apparatus. This impairs the function of the knee joint, and the uneven loading of the joint surfaces causes premature wear of the cartilage surfaces. Early arthrosis with permanent pain in the knee joint is the result.
Besides, a damaged ligament apparatus can be damaged again much more quickly than a previously healthy ligament apparatus. This can lead to recurrent strains or even tears of the knee joint ligaments. The chances of healing become worse and worse as a result and, if not treated, can lead to permanent instability of the knee ligament apparatus.
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Duration of ligament stretching in the knee
Stretching of the ligaments in the knee joint is a sensitive matter. Depending on the severity of the injury, it takes varying lengths of time before the joint can be fully loaded again.
The pain caused by a ligament stretching often subsides after just a few days. Cooling and reduced strain on the knee help to accelerate this process, so that the pain is no longer noticeable after 1-2 days.
However, the knee should be given 1-2 weeks to allow the injury to heal completely. During these weeks, you should also try to put as little strain on the leg as possible. Cooling, compression, and elevation of the leg, according to the PECH rule, will also accelerate the healing process.
In case of a severe ligament stretching in the knee, the healing process may also take longer. The knee should only be put under load again when the swelling has completely subsided, and the pain has disappeared.
You can start with sports activities as soon as you are completely pain-free for about a week, and the pain does not return even during sports activities. In order to support the stability in the knee, it is possible to wear support bandages even months after the injury. These reduce the risk of instability in the knee joint and prevent the development of arthrosis.
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Ligament strains in the knee do not necessarily require a sick note. People who are mainly sitting during their work are only on sick leave for a few days, if at all.
The duration of the sick leave depends on the severity of the ligament extension in the knee or the course of the injury.
After 1-2 weeks, most patients can resume their work without restriction, as the pain has disappeared.
Professional athletes are often on sick leave for longer periods. Too great is the risk of injuring oneself again if the patient returns to sport prematurely. Follow-up injuries are usually more serious and last longer than the first injury. Besides, there is also the risk of instability developing, which promotes joint wear and tear and thus increases the risk of arthrosis.
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Ligamental extension of the knee joint is one of the most common sports injuries. It occurs mainly in sports with rapid changes of direction and contact with opponents. The ligament stretching is usually harmless.
One distinction from a torn ligament is
- moderate swelling
- the absence of a bruise, and
- the existing stability of the knee joint
By temporarily protecting the affected ligaments with bandages or a stretching splint, the pain usually subsides quickly. In case of severe ligament stretching, a sports break of up to 8 weeks may be necessary. When the pain is gone, the affected knee joint can be slowly reloaded.
A full load and resumption of sporting activity is possible without the risk of a new injury if there is no pain. Only if further loading is applied under pain is there a risk of further injury to the ligaments, resulting in a torn ligament. In this case, the stability of the knee joint is limited and can lead to late consequences.
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