Patient question
My knee swelled up overnight and is too painful to touch. What is happening?
Dr. Pablo GelberOrthopaedic Knee Surgeon
Quick answer
A knee that becomes hot, swollen and exquisitely tender within hours, without an injury, is very often a crystal attack: gout or pseudogout. The same picture can be a joint infection, which is an emergency, so it needs a same-day assessment, advises Doha knee surgeon Dr. Pablo Gelber at Aman Hospital.
Why a knee can flare so fast
In gout, uric acid crystals form inside the joint. In pseudogout, the crystals are calcium pyrophosphate. When the body reacts to them, the lining of the knee becomes intensely inflamed within a few hours, which is why people often go to bed with a normal knee and wake up unable to let a sheet touch it.
The knee usually looks swollen, the skin over it may be warm or pink, and bending it even slightly hurts. Many patients say it is the worst pain they have had in the knee, yet there was no fall or twist.
Why infection has to be ruled out first
Septic arthritis, a bacterial infection inside the joint, can look identical in the first hours and can damage cartilage quickly. It is more likely if you have diabetes, a weakened immune system, a recent injection or operation on that knee, or a skin wound nearby.
Go to an emergency department the same day if you have any of these:
- Fever, shivering or feeling generally unwell
- You cannot put any weight on the leg
- Redness spreading up or down the leg
- A recent knee injection, arthroscopy or replacement on that side
What you can do in the meantime
Rest the knee, keep it raised and use a cold pack wrapped in a cloth for 15 to 20 minutes at a time. Drink water steadily, especially in the Qatar heat. Avoid alcohol and sugary drinks while it is flaring. If you already take a medicine to lower uric acid, do not stop it during an attack unless your doctor tells you to.
Anti-inflammatory tablets can help many people, but they are not suitable for everyone, for example with kidney disease, stomach ulcers or some heart conditions, so check with a doctor or pharmacist first.
How the cause is confirmed in Doha
The key test is drawing a small sample of fluid from the knee with a needle and examining it for crystals and infection. Blood tests and an X-ray add useful information. At Aman Hospital Dr. Gelber examines the knee, arranges these tests when they are needed and, once infection is excluded, treats the flare and plans with you how to prevent the next one.
Frequently asked questions
Can gout start in the knee rather than the big toe?
Yes. The big toe is the classic site, but the knee is commonly affected, and pseudogout favours the knee in particular.
How long does a flare like this last?
Untreated, a crystal flare often settles over one to two weeks. With prompt treatment many people improve noticeably within a few days.
Should I wait to see if it goes away by itself?
Not with a first episode. Because infection can look the same, a hot, swollen knee without injury should be assessed the same day.
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