Magnetic resonance imaging of the knee is an examination that can most accurately visualize the structures of the knee joint and detect diseases or abnormalities within it. The advantages of this technique, however, include not only accuracy, but also safety during the test. What are the indications for an MRI of the knee and how should you prepare for it? When should I do a MRI with contrast, and when without?

Magnetic resonance imaging of the kneeis performed in the event of any abnormalities in the knee joint. The knee joint is a unique joint in the human body. It is distinguished by the fact that it is subjected to the greatest loads and a complicated structure. The knee joint consists of bones (tibia and femur), menisci, joint capsule and ligaments. Considering that the knee joint constantly carries the weight of the whole body, its structures quite often suffer various injuries. Their gradual degeneration may also occur with age or as a result of accidents.

Magnetic resonance imaging of the knee: types

Magnetic resonance imaging (MRI for short) is a fairly general term. There are different types of this research.

In the case of knee imaging, the examination can be performed without or with the use of a contrast agent. When contrast is to be administered, the test is referred to asMRI of the knee .

Most often, the contrast agent is applied to the knee joint itself (then the test is calleddirect arthrography ). More rarely, contrast in knee resonance is administered intravenously (in this case, the examination is referred to asindirect arthrography ).

Magnetic resonance imaging of the knee with contrast is especially recommended when there is a suspicion of damage to the smallest elements of the knee joint, such as the meniscus.

The administration of a contrast agent before the examination increases its diagnostic value. This allows, for example, to significantly reduce the risk of a false-negative result.

A false negative result indicates a situation whereno pathological process is found during the examination, despite its presence in the patient.

Magnetic resonance imaging of the knee: indications

Magnetic resonance imaging of the knee joint is recommended when suspecting various defects of this structure. The examination may be recommended, inter alia, people who:

  • have experienced some lower limb injury,
  • struggle with chronic knee pain,
  • experience swelling of the knee joints for a long time,
  • have varying degrees of mobility difficulties, the suspected cause of which is some defect in the knee joint.

MRI of the knee: what does it detect?

The specific pathologies that can be detected thanks to MRI of the knee include:

  • degenerative changes in the knee joint,
  • damage to tendons, ligaments or cartilages of the knee joint,
  • meniscal damage,
  • osteochondral necrosis,
  • Baker's cyst,
  • synovial hypertrophy of the knee joint,
  • fractures of the bones that make up the knee joint,
  • presence of free godfathers or bones torn off as a result of the patient's experience of some trauma.

Magnetic resonance imaging of the knee: safety

Many patients, before various tests, are concerned about whether their performance is associated with any risk to their he alth. In the case of MRI of the knee, it can be said that the examination is safe. Its performance is not related to, for example, the patient's exposure to ionizing radiation (as is the case with computed tomography or taking X-rays).

As always, however, there is some risk and it applies to tests using contrast agents. After their administration, the patient may develop an allergic reaction, but this happens generally relatively rarely.

Magnetic resonance imaging of the knee: contraindications

There are very few contraindications for performing an MRI of the knee. During the test, a strong electromagnetic field is generated, which has the ability to attract various metals.

Today, many people have various metal implants in their bodies, e.g. dental implants, pacemakers, neurostimulators and endoprostheses, and some use orthodontic appliances.

In the past, having this type of implants was an unconditional contraindication to magnetic resonance imaging. Currently, however - thanks to technological progress - more and more oftenmedical devices are made of materials that do not become magnetized.

Therefore, it is worth having a document informing about the material of the dental implant or pacemaker.

In the case of magnetic resonance imaging of other structures, e.g. head resonance - claustrophobia is a contraindication to the examination.

Magnetic resonance imaging of the knee is usually performed in the so-called open resonance, so there is no need to stay in a confined space. Thanks to this, even people with claustrophobia should not feel anxious while performing the test.

Magnetic resonance imaging of the knee: preparation

In fact, the MRI of the knee does not require any intensive preparation from the patient. Before thetest, remove any metal objects , such as e.g. rings or earrings.

It is also worth going to the medical facility in comfortable, metal-free clothing. Shortly before the examination, it is advisable to test the concentration of creatinine in the blood - it is not always required, but it is worth knowing its level, especially in a situation where the patient is to be administered a contrast agent.

Magnetic resonance imaging of the knee: waveform

MRI of the knee may surprise some patients. When the examination is to be carried out without the contrast agent, the subject does not even have to undress in front of it. The procedure is usually performed lying down, and only the patient's lower limb is within the reach of the MRI machine. Sometimes it is specially stabilized, because moving it during the test may negatively affect its result.

The test lasts from about 20 to 60 minutesand it is painless. Pain may be experienced by those patients who are administered a contrast agent. Immediately after an MRI of the knee without contrast, the patient can return to his normal activities. The situation is slightly different, however, when a test is carried out with the use of a contrast agent.

In the case of direct arthrography, i.e. the one where contrast is administered directly into the joint cavity, patients may complain of pain in the lower limb and have difficulties in moving after it is performed - these usually disappear within a maximum of about 24 hours, however, it is worth making sure that someone helps the patient to get home after the examination.

Magnetic resonance imaging of the knee: price

MRI of the knee can be donefree of charge under the NHF . It is then necessary to have a referral. Getting a referral for research alone is probably not a bigger problem.However, the waiting time for its implementation may be a great difficulty, which in Polish he alth care may last several or even several months.

Due to the long waiting times, many patients choose to perform an MRI of the knee in commercial medical facilities. In such a situation, you should take into account the costs offrom 300 to even 1000 PLN .

It should also be mentioned that the cost of the test typically increases when a contrast agent is to be used.

  • Magnetic resonance imaging of joints
  • Knee Injuries: Symptoms and Diagnosis
  • Arthroscopy - a test used in the diagnosis and treatment of joint diseases
  • Knee treatment - maintaining mobility

Category:

Research