Knee Clicking, Popping and Grinding

What knee clicking usually means

Knees make noises. A crack when you stand up, a click as you climb stairs or a soft crunch under the kneecap when you squat are reported by a large share of healthy people, including young athletes. These sounds usually come from tiny gas bubbles in the joint fluid, from tendons or soft tissue sliding over bone, or from slightly uneven surfaces behind the kneecap. On their own they are not a sign that the knee is wearing out.

Doctors call the noise crepitus. What turns it into something worth checking is what comes with it: pain at the same moment, swelling afterwards, the knee catching or locking, or a single loud pop during an injury.

Common causes and how they tend to feel

• Harmless joint noise: a click or crack with no pain and no swelling, often on standing up or the first few steps, that may come and go
• Patellofemoral pain or chondromalacia patella: crunching or grinding under the kneecap on stairs or squats, together with an ache at the front of the knee
• Meniscus tear: a click with pain on the inner or outer joint line, often with twisting or deep squats, and sometimes catching or locking
• Loose body or cartilage flap: a sudden catch or block that releases with a click, sometimes after a cartilage injury or osteochondritis dissecans
• Plica syndrome: a snapping or clicking at the inner front of the knee with an ache, often in active young people
• Discoid meniscus: a loud clunk on the outer side in children and teenagers
• Osteoarthritis: a coarse grinding with stiffness and aching in older knees
• A loud pop at injury: when it is followed by swelling or giving way, often an ACL tear or kneecap dislocation

What you can do now at home

If the noise is painless and the knee does not swell, you do not need to avoid exercise. Strengthening the thigh and hip muscles often makes noisy kneecaps quieter and more comfortable, and staying active is good for joint cartilage.

If clicking comes with pain, ease off whatever provokes it, such as deep squats, heavy lunges or twisting sports, for a couple of weeks. Gentle cycling, swimming and flat walking are usually fine. Ice helps if the knee is sore after activity. In the gym, reduce load and depth rather than stopping training completely, and build back gradually.

Red flags that need urgent care

• A loud pop during sport followed by swelling within hours or the knee giving way
• The knee locks and you cannot straighten it
• You cannot bear weight after the pop
• The kneecap shifted out of place
• A hot, red, swollen knee with fever

These need prompt assessment, and a locked knee should be seen the same day where possible.

How a knee surgeon in Doha works it out

Dr. Gelber asks when the noise started, whether it hurts, whether the knee swells or catches, and whether there was an injury. On examination he listens and feels for where the click comes from while you bend and straighten the knee, checks the kneecap's tracking, presses along the joint lines, and performs meniscus and ligament tests.

Painless clicking with a normal examination usually needs no scan at all. X-rays help when arthritis or a loose body is possible. MRI is useful when clicking comes with pain on the joint line, catching, locking or swelling, because it shows meniscus tears, cartilage flaps and loose pieces.

When to book at Aman Hospital

Book an assessment if clicking comes with pain, if the knee catches, locks or swells, if a child's knee clunks or will not fully straighten, or if you heard a pop during sport. Painless noise on its own can usually be watched. When there is a mechanical cause, such as a torn meniscus flap or a loose body, keyhole surgery can sometimes resolve it, but many patients improve with physiotherapy first.