Read below about knee stiffness, including causes, treatment options and remedies. Or get a personalized analysis of your knee stiffness from our A.I. health assistant. At Buoy, we build tools that help you know what’s wrong right now and how to get the right care.

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Knee Stiffness Symptoms

The knee is the largest and most stressed joint in the entire human body. It is a complex system of bones, cartilage, ligaments, tendons and muscles responsible for weight-bearing and movement. The knees are used for every movement – walking, stepping, sitting, and even standing – as a result, the knee is susceptible to various conditions that can cause knee stiffness symptoms and discomfort.

Most people, regardless of age, experience knee stiffness symptoms and discomfort at some point in their lives. Older individuals may experience knee pain and discomfort due to multiple age-related conditions, and younger individuals may experience similar symptoms due to sports or other physical activities.

Regardless of the cause, you may also experience other symptoms in addition to knee stiffness symptoms:

Usually stiffness in the knee is easily treated and not a sign of serious injury. However, knee stiffness symptoms can be associated with trauma and severe damage.

Stiffness associated with injury may also include symptoms such as:

If you notice stiffness in the knee and any of these associated symptoms, make an appointment with your doctor promptly.

Knee Stiffness Causes Overview

Stiffness in the knee happens due to inflammation or injury to the components of the knee.

The components of the knee include:

  • Bones: The femur (thigh bone), patella (kneecap) and tibia (shin bone). The actual knee joint works to keep these bones securely in place.
  • Cartilage: The meniscal and articular cartilage act as cushions around the bones that reduce friction during movement and help the bones move smoothly against each other. There is a medial meniscus on the inner side of the knee and a lateral meniscus on the outer side of the knee.
  • Ligaments: The knee has four ligaments that connect bones to other bones and promote stability: collateral, lateral collateral, posterior cruciate and anterior cruciate ligaments. These ligaments prevent the side to side movement of the femur as well as excessive backward and forward movement of the femur and tibia.
  • Tendons: Tendons are like ligaments but connect bone to muscle (instead of bone to bone). The patellar tendon is the largest tendon of the knee and attaches the quadriceps to the patella and then the patella to the tibia.
  • Fluid: The joint capsule and bursa are fluid filled membranes that lubricate the joint and reduce friction.

See this image for a visual representation of these many components of the knee and how they connect and work together.

Knee stiffness is always the result of an underlying problem and should always be followed-up by a medical professional.

Trauma-related causes such as knee injury.

Stiffness after trauma may be difficult to recognize due to the pain that accompanies traumatic knee events. Usually these injuries are not subtle, but in the case that they are, stiffness may be the first symptom.

  • Fracture: A fracture is defined as a broken bone. Patella (kneecap) fractures are most common and are usually the result of a direct, hard blow or a fall, especially in older patients.
  • Sprain: A sprain is defined as a twisting or stretching of a ligament. Any of the four knee ligaments can be sprained in activities that causes bending, twisting, sudden movement, or direct impact. Sports that are often associated with ligament sprain include football, skiing, soccer, and rugby.

Inflammation-related causes:

  • Arthritis: Arthritis is a general term for multiple conditions that cause painful inflammation and stiffness of the bones and joints. Arthritis can affect the bones and fluid-filled areas of the knee resulting in significant irritation that can cause chronic stiffness, discomfort, and pain.

  • Infection: Inflammation in the knee due to infection is rare but can occur when bacteria enter the knee via a cut or other incision. The fluid filled bursae and joint capsule can become infected and inflamed. Sometimes, stiffness in an infected knee is also difficult to recognize because this cause is usually more associated with excruciating pain that makes even tiny movements of the knee unbearable.

Environmental causes:

  • Exercise-induced: Muscles that are over-worked without proper conditioning and stretching can become tight and weak. This can make all parts of the leg, including the knee, feel stiff.
  • Positional: Exercise can cause knee stiffness symptoms but being sedentary can lead to stiffness as well. Situations such as long flights or desk jobs in which you are sitting for prolonged periods of time can result in stiff knees.

6 Potential Knee Stiffness Causes

Disclaimer: The article does not replace an evaluation by a physician. Information on this page is provided as an information resource only, and is not to be used or relied on for any diagnostic or treatment purposes.

  1. 1.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.

    Knee arthritis is a chronic problem once it develops.

    Top Symptoms:
    pain in both knees, knee stiffness, knee instability, swollen knee, morning joint stiffness
    Symptoms that always occur with knee arthritis:
    pain in both knees
    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.

    6 to 8 weeks

    Top Symptoms:
    pain in one knee, knee stiffness, knee instability, pain in the inside of the knee, swollen knee
    Primary care doctor
  3. 3.Rheumatoid Arthritis

    Rheumatoid arthritis (RA) is a form of arthritis that causes pain, swelling, stiffness and loss of function in your joints. It can affect any joint but is common in the wrist and fingers. RA is an autoimmune disorder, meaning that it is caused by the immune system incorrectly attacking the joints when it shouldn't.

    RA is a chronic disease which requires lifelong control.

    Top Symptoms:
    fatigue, depressed mood, joint pain, muscle aches, daytime sleepiness
    Primary care doctor

    Knee Stiffness Checker

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  4. 4.Osteochondritis Dissecans

    At joints where bones meet, bones are covered with a layer of cartilage which provides shock absorbance and lubrication. Osteochondritis dissecans is a condition where a piece of cartilage with a thin layer of bone detach from the larger bone, causing pain.

    Conservative treatment should resolve the problem in 3-6 months.

    Top Symptoms:
    pain in one knee, knee stiffness, knee instability, knee pain that gets worse during a run, pop in the knee
    Primary care doctor
  5. 5.Jumper's Knee (Patellar Tendonitis)

    Patellar tendonitis (Jumper's knee) is the inflammation of the patellar tendon, which attaches the knee cap to the shin bone (tibia). This condition is caused by frequently from sports and jumping.

    1 month with rest

    Top Symptoms:
    pain in one knee, spontaneous knee pain, knee pain that gets worse when going up stairs, knee stiffness, knee pain that gets worse when squatting
    Primary care doctor
  6. 6.Septic Arthritis

    Septic arthritis is an intensely painful joint infection.

    12-14 days with treatment

    Top Symptoms:
    fever, spontaneous shoulder pain, chills, knee pain, joint pain
    Hospital emergency room

Knee Stiffness Treatments and Relief

Treatment for knee stiffness often starts at home with simple lifestyle changes. The RICE (Rest, Ice, Compress, Elevate) mnemonic is an often-used, guide for treating stiffness and swelling of the knee:

  • Rest: Limit weight bearing of the affected knee or knees as much as possible. Your doctor may suggest crutches.
  • Ice: Put an ice pack on your knee or place your knee in ice water every 15 minutes in order to reduce any swelling.
  • Compression: Protect your knee from unnecessary movement by using a stretchy bandage or compression wrap with a protective brace. Compression like this can also help with swelling.
  • Elevation: Raising your leg and knee above the level of your heart can also help reduce swelling and bruising.

If you find yourself sedentary for many hours of the day, like during work, for example, prevent knee stiffness by getting up to move every 30 minutes or so to help lubricate the knee.

However, if your knee stiffness symptoms are persistent or associated with any of the red-flag symptoms above, seek prompt medical attention.

Your doctor may suggest:

  • Physical therapy: After many knee injuries, your doctor will suggest physical therapy in order to restore range of motion, strength and stability to your knee.
  • Medication: If your severe knee pain is due to inflammatory conditions, your doctor may prescribe antibiotics to treat an infection or anti-inflammatory medications to treat arthritic conditions.
  • Surgery: Fractures and tears of the ligaments and cartilage of the knee often require surgical intervention.

Questions Your Doctor May Ask About Knee Stiffness

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

If you've answered yes to one or more of these questions, try our knee stiffness symptom checker to find out more.

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Knee Stiffness Symptom Checker Statistics

  • People who have experienced knee stiffness have also experienced:

    • 18% Knee Pain
    • 6% Knee Locking
    • 6% Knee That Clicks During Movement
  • People who have experienced knee stiffness had symptoms persist for:

    • 39% Over a Month
    • 20% Less Than a Week
    • 18% Less Than a Day
  • People who have experienced knee stiffness were most often matched with:

    • 41% Meniscal Injury
    • 5% Rheumatoid Arthritis
    • 3% Knee Arthritis
  • Source: Aggregated and anonymized results from visits to the Buoy AI health assistant (check it out by clicking on “Take Quiz”).

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