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Buckling Knee Checker

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Your Buckling Knee May Also be Known as:
Knee buckling
Knee giving out

Buckling Knee Symptoms

How embarrassing! You were just walking down the street, minding your own business, when your knee gave out on you. You slipped and fell in front of what felt like half the town. In all honesty, the only person who saw you was the mailman.

What you've just experienced is a buckling knee. It can occur to just about anyone and at just about any time. But if you ask someone who experiences knee buckling on a regular basis, you'll find out that the event is annoying, sometimes embarrassing, and becomes more concerning the more it happens.

If you think you have a buckling knee, you might be experiencing:

Our knees take a lot of damage over the course of a lifetime. Some of the most important bones in our body meet at the knee. The knee cap, or patella, sits in front of the femur and tibia. The leg bones meet directly behind the patella where they are cushioned with articular cartilage. The bones are connected by the anterior cruciate ligament and patellar tendon.

These parts usually work in harmony, providing a fluid motion that results in the bending of the knee that's required for walking or running. But when something is damaged or just not working right, the result can be a knee that can't function properly and buckles instead of bends.

Let's start determining the cause of your buckling knee so that you can begin to treat any existing condition or get moving on preventing the issue from happening again.

Buckling Knee Causes Overview

If your buckling knee seems like an isolated incident, you might not need to determine a cause quite yet.

But if your knee seems to be giving you problems on a regular basis, consider the following cause categories.

  • Traumatic causes are common: Whether you're a seasoned athlete or hit the gym once a month, moving your knee in the wrong direction can cause trauma that leads to an unstable knee joint. In mild cases, a little rest should solve the problem. But in more serious traumas, such as when a ligament or tendon is damaged, healing can take more effort and time.

  • Serious medical causes are rare, but they are possible: A treatable example would be chondrocalcinosis, which is a build-up of calcium in the knee. Another common medical cause behind a buckling knee is arthritis. Arthritis isn't curable but there are ways to minimize its effects on the body.

  • There are other causes behind buckling knees that aren't related to trauma or disease: Aging can be a factor. It's incredibly rare for a child to experience a buckling knee but for those much further along in life, a buckling knee can be just another aging symptom like wrinkles or hair loss.

Top 5 Buckling Knee Causes

  1. 1.Patellofemoral Pain Syndrome

    The kneecap (patella) is located directly in front of the thigh bone (femur), and should normally glide freely up and down. In this condition, called patellofemoral pain syndrome, the kneecap may rub against the thigh bone instead of gliding smoothly, causing damage and pain.

    You should visit your primary care physician. While you can safely take steps to treat this condition at home (avoiding strenuous use of the knee and taking over-the-counter pain medication), your doctor may coordinate care with a physical therapist to help manage your pain and function of the knee.

    Top Symptoms:
    knee pain, pain in one knee, knee pain that gets worse when going up stairs, dull, achy knee pain, knee pain that gets worse when squatting
    Symptoms that always occur with patellofemoral pain syndrome:
    knee pain
    Primary care doctor
  2. 2.Meniscal Injury

    A torn meniscus is one of the most common knee injuries. Any activity that causes forceful twisting of the knee, especially when putting the pressure of one's full weight on it, can lead to a torn meniscus.

    Conservative treatment such as rest, ice and medication is sometimes enough to relieve the pain of a torn meniscus and give the injury time to heal on its own. In other cases, however, a torn meniscus requires surgical repair, which can be best determined by your doctor or physiotherapist.

    Top Symptoms:
    pain in one knee, knee stiffness, pain in the inside of the knee, knee instability, knee pain from an injury
    Primary care doctor

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  3. 3.Knee Arthritis

    Arthritis is inflammation of one or more of the joints. Pain, swelling, and stiffness are the primary symptoms of arthritis. Any joint in the body may be affected by the disease, but it is particularly common in the knee.

    You should visit your primary care physician who will likely coordinate care with an muscle and bone specialist (orthopedic surgeon). Treatment for arthritis may involve pain killers to ease the pain, corticosteroid injections into the knee, and surgery in rare, more severe, cases.

    Top Symptoms:
    pain in both knees, knee stiffness, morning joint stiffness, knee instability, swollen knee
    Symptoms that always occur with knee arthritis:
    pain in both knees
    Primary care doctor
  4. 4.Repeated Kneecap Dislocation (Patellar Subluxation)

    Recurrent patellar subluxation is the continued instability of the kneecap, which causes anterior knee pain and usually occurs laterally. It occurs unpredictably with varying durations.

    Your doctor will be able to make a diagnosis regarding the severity of your recurrent patellar subluxation using X-ray and/or MRI. Basic rehabilitation is the preferred conservative treatment, but in certain cases surgery may be necessary to stabilize the recurring dislocations.

    Top Symptoms:
    pain in one knee, dull, achy knee pain, pain in the front of the knee, pain in the inside of the knee, swollen knee
    Symptoms that always occur with repeated kneecap dislocation (patellar subluxation):
    kneecap dislocation
    Primary care doctor
  5. 5.Severe Kneecap Dislocation

    The kneecap connects the muscles in the front of the thigh to the shinbone (tibia). When the kneecap slips out of the groove, problems and pain often result.

    You should seek immediate medical care at an urgent care clinic or ER, because this is a concerning type of knee dislocation that cannot be easily pushed back in place (reduced). A consult from an orthopedic surgeon may be needed to evaluate possible damage.

    Top Symptoms:
    constant knee pain, pain in one knee, knee injury, knee pain from an injury, swollen knee
    Symptoms that always occur with severe kneecap dislocation:
    knee pain from an injury, kneecap dislocation, constant knee pain
    Hospital emergency room

Buckling Knee Treatments and Relief

You should never ignore a buckling knee. In most cases, home treatment is all you need. But there are signs that point to a doctor's visit.

Call your doctor if you experience any of the following:

The following treatments could have your knee functioning properly again.

  • RICE Technique: The RICE method can be applied if an injury is suspected. Rest the knee, Ice it for 20 minutes at a time, use Compression when possible, and keep the leg Elevated.
  • Medication: If the pain is intense, NSAIDs, such as Motrin or Advil, can be taken for relief.
  • Supportive Device: If further support is needed, knee braces can be put in place to facilitate movement while the tissues are healing.
  • Surgery: Severe cases may require surgery. If there are bone or tissue fragments present in the joint, surgical removal is needed to prevent further injury and restore the fluid motion of the knee.

Knee buckling is a simple health issue, but learning its cause and determining a treatment can save you from annoying and embarrassing moments. If your knee isn't improving on its own, it may get worse with time, so start the search for a cause and cure sooner than later.

FAQs About Buckling Knee

Here are some frequently asked questions about buckling knee.

What does it mean when your knees lock up?

Knee locking is most commonly caused by meniscal tears, often from a traumatic incident or constant wear and tear. Knee buckling can be a sign of osteoarthritis of the knee, tears of a portion of cartilage called the "meniscus," or a tear if a ligament or muscle. These tears can often be contoured or repaired by orthopedic surgeons, and if knee locking is severely limiting your mobility, you may want to consider surgery.

Can arthritis lead to knee buckling?

Osteoarthritis or arthritis from old age can lead to knee buckling. Osteoarthritis is caused from inflammation and a wearing away of the cartilage of the "articular" contact surfaces of the joints. It happens frequently in the hips and knees. This loss of cartilage and break down of bones on the surfaces where they contact each other can "roughen" the surfaces, and cause them to catch on each other — causing knee buckling.

Can buckling knees mean a torn ligament?

Yes. A torn ligament can cause knee buckling as it can destabilize connections between bones. More commonly, a torn tendon will cause knee buckling, because tendons attach muscle to bone, and detaching muscle from bone will keep a muscle from being able to exert force on a knee. If you tear a tendon, you may also have a bulge of the associated muscle as it is no longer connected to bone. It may bunch in an area of the leg or arm causing a grossly enlarged muscle, often called the "Popeye" effect after the cartoon character whose muscles buldged out after eating spinach.

What does it mean if your knees give out?

Knees can give out for a variety of reasons. The body monitors the amount of force placed on a muscle, and in certain situations, if you exceed that force, the muscle will "give out" to protect itself from being torn. However, a knee will also give out if a muscle is torn, or can give out from wear and tear on bones from osteoarthritis.

When should you seek medical attention for buckling knees?

Knee buckling in the absence of strenuous activity is abnormal and you should seek medical attention if this happens. If your knees buckle during strenuous activity, and you experience residual pain, "grinding," inability to bear weight, or knee locking, you should seek medical attention. The doctor may test the "range of motion" of the knee or move it through a series of positions to evaluate it and then help you develop a treatment plan or refer you to a specialist.

Questions Your Doctor May Ask About Buckling Knee

  • Q.Which of the following describes your physical fitness:
  • Q.Do you feel like your knee is unstable, weak, or giving out?
  • Q.How would you explain the cause of your knee pain?
  • Q.Is the knee pain affecting one or both knees?

If you've answered yes to one or more of these questions, check our buckling knee symptom checker.

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Buckling Knee Symptom Checker Statistics

  • People who have experienced buckling knee have also experienced:

    • 9% Knee Pain
    • 6% Knee Stiffness
    • 6% Pop in the Knee
  • People who have experienced buckling knee were most often matched with:

    • 58% Patellofemoral Pain Syndrome
    • 40% Meniscal Injury
    • 1% Knee Arthritis

Buckling Knee Checker

Take a quiz to find out why you’re having buckling knee.

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