We associate popping and snapping sounds with breaking, so it’s understandable that a noisy knee might make you pause or wonder, “Why is my knee popping?”
Unfortunately, there is no single definitive answer. Knee popping is very common and occurs for a variety of reasons, ranging from the relatively benign to the potentially worrisome.
To help you better understand the symphony range of your knees, we talked to a few medical experts to get their take on the knee, when to see a doctor, and how to keep your knees healthy.
What causes the knee to pop or break?
Knee popping, clicking or popping sensations and sounds have various causes. Here are some of the most common culprits:
1. Gas bubbles
“Normal popping and cracking can be from negative pressure building up in a joint, which causes gas bubbles to form, resulting in that sometimes scary noise you hear,” he says. Dr. Timothy Gibson, MDorthopedic surgeon and medical director of the MemorialCare Joint Replacement Center at Orange Coast Medical Center in Fountain Valley, California.
“This phenomenon is most common in your joints, but it can also happen in the knees,” she explains. Gas bubbles are usually painless and not worrisome.
2. Web traffic
It’s possible that knee cracking can be caused by friction between the various structures of your knee, he says Dr. Steve Yoon, MDdirector of The Regenerative Sports and Joint Clinic at Cedars-Sinai Kerlan-Jobe Institute in Los Angeles, California and chief team physician for the Los Angeles Clippers.
“Knee popping can come from inside or outside the joint,” he explains. “Within the joint, cracking can be caused by irregular surfaces of cartilage rubbing or articulating against each other. “Outside the joint, there are tendons that can tighten and become inflamed, which can move and tear over other surrounding structures.”
In many cases, rest, ice, and over-the-counter anti-inflammatory medications can help relieve symptoms, but a doctor should evaluate any significant knee pain or swelling.
3. Meniscal tears
The meniscus is a piece of cartilage in the knee that provides cushioning and stability. When it’s torn – usually due to aggressive twisting and turning, deep bending or degeneration of the joint – you may experience popping in the knee as well as a feeling of locking or instability, pain, swelling and difficulty bending and straightening the knee.
A doctor should evaluate a meniscal tear. “Meniscal or cartilage tears are often treated with arthroscopic or microsurgery to remove a damaged or torn piece of tissue,” says Dr. Gibson.
In some cases, rest, ice, and over-the-counter medications are recommended. Physical therapy may also be recommended.
4. Plica syndrome
Common among runners and athletes, plica syndrome can lead to clicking and popping in the knee, he says Dr. Joseph J. Ciotola, MDorthopedic surgeon at Orthopedics and Joint Replacement, Mercy Medical Center in Baltimore. “The plica is a fold of the lining of the knee and is caught between the patella and the femur,” he says.
In some cases, the resulting kneecap is painless and not a cause for concern. However, if the knee becomes inflamed, arthroscopic surgery may be required to trim or remove the tissue.
5. Arthritis
Dr. Ciotola says the knee crack, which is a creaking or cracking sound (like the sound of crumpling a plastic bag) may be an early sign of osteoarthritisa condition that causes cartilage to wear down.
Osteoarthritis is a chronic but manageable condition, with treatments including cortisone or lubricant injections.
Treatments for cracked and broken knees
“Painless popping and popping knees are usually normal and don’t need any treatment,” says Dr. Gibson. “Painful popping of the knee may respond to rest, ice, elevation, and avoidance of the activity that causes the pain.”
Depending on your specific situation, your healthcare provider may recommend one or more of the following treatments.
1. Physiotherapy
“Physical therapy can sometimes help by strengthening the muscles surrounding the painful, noisy knee,” says Dr. Gibson.
2. Injections
Steroid or an injection of gelatinous hyaluronic acid “may lubricate the joint and help temporarily,” says Dr. Gibson. “Biologic injections, such as stem cells, are used by some, but they are still under investigation and are very expensive.”
3. Surgery
“Mechanical locking and seizing of a knee, due to a meniscal or cartilage tear, is often treated with arthroscopic or microsurgery to remove a damaged or torn piece of tissue,” says Dr. Gibson.
When should I worry about noisy joints?
A sprained knee by itself is not usually a cause for concern. Consult a doctor if you experience persistent:
- Discomfort or pain that does not go away or gets worse over time
- Swelling
- Mechanical locking of the knee
A doctor can perform a physical examination, recommend further tests (e.g. MRI) and prescribe the appropriate treatment.
Tips for healthy knees
“The best way to maintain healthy knees is to avoid injuring them in the first place,” says Dr. Gibson. Here are some ways to protect your knees:
1. Maintain a healthy weight
This is the first thing most doctors will tell you. “Your knees feel four extra pounds of reactive joint force with every extra pound of body weight,” says Dr. Gibson. Keeping your weight in a healthy range will reduce the load on your joints and help reduce wear and tear.
2. Low impact
High-impact activities that pound the joints, like running and jumping, can worsen knee pain and even worsen conditions like osteoarthritis, according to Dr. Ciotola.
“Most arthritis is genetic, but you can accelerate it by banging on the joints,” he says. Low-intensity exercise, such as cycling or swimming indoors, can keep you in shape without harming your joints.
3. Don’t skimp on strength training
Strength training offers countless benefits, but specifically building the muscles around your knee can help alleviate joint pain associated with cartilage loss, Dr. Ciotola says.
“Keeping the quad muscles strong around the knee will help patients tolerate arthritis symptoms much better,” he says. “People who have very strong legs will tolerate a very worn joint much better than a couch.”
4. Focus on your form
While exercise can help with knee pain, be sure to increase your weight gradually and make sure your form is on point when you squat or lunge.
“Lifting heavy weights with bad form is probably the worst thing you can do [for your knees]says Ciotola. “This is just a set up to break down the cartilage.”
5. Get evaluated by a physical therapist
Physical therapy is not just a form of treatment. A physical therapist can identify muscle imbalances and faulty movement patterns that, over time, can lead to injuries. Stretching, mobility, and strengthening exercises can help keep your knees functioning and feeling good.
