My knee suddenly hurt – what’s the cause?

Pain in the knee is most often caused by it being twisted or hit. Sometimes just standing up from a squat is enough to break something in the knee. Specialist in orthopedics and traumatology Tuomo Karila in his work, he has to deal with a lot of questions about injury energy, i.e. the force that is enough to damage human structures.

– The patient may say that nothing has happened to the knee and that he has not done anything exceptionally strenuous, such as running a marathon. Then you have to think about whether there is something in the background that has put the knee in such a condition that even a low-energy injury can damage it. When there is degeneration in the tissues, the strain or damage does not have to be significant to hurt, says Karila.

If you have knee pain, you should ask yourself: has the knee ever been operated on, have artificial joints been put in in the family already for young people, or has excess weight accumulated? Has the pain continued for a long time, does the knee swell, is it hot or stiff and does it feel like the knee is buckling, locking or the legs are giving out from underneath?

For example, a long hike in the cold may irritate the already healthy knee of a young person.

– Sometimes patients say that the pain started suddenly – on Monday morning!

However, people are resourceful to compensate. With a sore knee, we go by car and try to find a parking space so that we don’t have to walk for a long time. In the shop, people lean on carts to rest their knees. You go to the doctor when you can’t get around the pain anymore.

Rigidity is not the cause but the effect

Even if you don’t remember, the articular cartilage may have been damaged in connection with a spiral tear or a hard blow years ago. A small injury has started the inflammatory process. This inflammation of the knee, i.e. low inflammation, destabilizes the balance of neurotransmitters that build and break down the joint.

– In this case, the articular cartilage begins to become brittle and the articular cartilage, which acts as a shock absorber, deteriorates and softens. The joint capsule thickens and stiffens. The body starts making bone spurs – we’re talking about osteocytes. In this way, nature tries to stiffen the joint so that it is not subjected to such a heavy strain, explains Karila.

This feels like a pain that strikes when you put weight on the leg while walking or standing. Sometimes the knee becomes so inflamed that fluid accumulates there. In a healthy joint, the fluid flushes and nourishes the articular cartilage, which has no blood vessels or nerves. If too much fluid is produced, the knee will swell.

– Because the liquid does not clump together, a feeling of pressure and stiffness is created. A lump of fluid that appears at the back of the knee is called a Baker’s cyst. Then the knee is stiff and doesn’t want to bend. It is not a cause, but a consequence of the knee problem.

Morning friction tells about rheumatism

If a short course of anti-inflammatory drugs, a knee brace and cold packs do not relieve the pain, you should see a doctor. A clear sign of inflammation is joint swelling. Reactive arthritis most often occurs after a bacterial infection, for example salmonella or campylobacter infection. In this case, the joint becomes sensitive and swollen. Cold wraps and anti-inflammatory drugs make you feel better, if necessary, the doctor can inject cortisone into the joint. The inflammation often subsides within 3-5 months.

Rheumatoid arthritis, on the other hand, is an autoimmune disease in which inflammatory cells attack your own joints. It is characterized by morning stiffness, pain and swelling.

– Nowadays, there are good rheumatism drugs that keep the disease under control, says Karila.

A mushroom, for example, with a painkiller

If it is osteoarthritis, the pain is in the lower leg, thigh and back of the knee. Unfortunately, there is no medicine that would even slow down the progression of the disease. If the knees swell, the inflammation is soothed with injections of cortisone or hyaluronate.

– You can take glucosamine or chondroitin sulfate orally. There is no scientific proof of their effectiveness, but quite a lot of people benefit from them. Joint products available without a prescription from a health food store or pharmacy can be used if they help with symptoms and keeping you moving.

The basic medicine for joint pain is paracetamol. Next come anti-inflammatory drugs, but when used for a long time, they are not good for the stomach, kidneys or heart. However, they are effective and suitable for short-term use.

– I often tell the patient that if you want to go to the mushroom, you can take burana, that you will survive the forest trip, advises Karila.

What kind of movement for a sore knee?

An osteoarthritis patient is between a stick and a stick: even if movement feels a little bad, it is a better option than immobility. However, not all exercise is suitable for fragile feet. For example, cycling, swimming, walking and gym training are good sports. Walking in the forest, on uneven but soft terrain, is good for the joints and improves balance. At the same time, the mind is refreshed.

Instead of the elevator, you should choose the stairs and increase your daily exercise anyway, because the steps will then go unnoticed. Regularity is important in exercise medicine, but so is moderation: if you do it too quickly and too much, your knee can get sprained. Hard and impactful exercise should be avoided.

Walking sticks lighten the load on the knee and invigorate the blood circulation in the neck-shoulder area. If the knee feels unstable or bulging, a knee support (neoprene support) can help. It brings one more way to control the knee and gives courage to move.

At what stage is the artificial joint?

As osteoarthritis progresses, there is night pain, which worsens sleep, endurance and mood. If the knee pain is such that you often have to resort to strong painkillers containing codeine or tramadol, and the x-ray shows clear osteoarthritis, the scale starts to tilt towards joint replacement.

– The most important reason for an artificial joint is pain management. Because an artificial joint is never as good as the one made by “mother”, for example, it is not as flexible, says Karila.

Although surgeries are being performed on younger people, it is not the primary option. You can often fight procrastination with the help of, among other things, physiotherapy, pain management, exercise and joint products.

When to see a doctor?

1. If the pain taxes the ability to function.
2. If you can’t walk properly.
3. If the knee gives out from below, swells, feels hot and cannot be stretched straight.

Tuomo Karila, a specialist in orthopedics and traumatology, is the expert

This article has appeared in Hyvä tervey magazine. As a subscriber, you can read all issues free of charge from the digilehdet.fi service.