Signs Your Knee Cartilage May Be Damaged

By Your Health Magazine Health Information Team

Common signs of knee cartilage problems include pain during weight-bearing activity, swelling, stiffness, reduced movement, grinding or catching sensations, and a knee that locks or gives way. Symptoms may appear suddenly after a twist or impact, or develop gradually over months or years. Because ligament injuries, tendinitis, bursitis, gout, infection, and other conditions can produce similar symptoms, a medical evaluation may be needed to determine the cause.

What Does “Knee Cartilage” Mean?

The knee contains two main types of cartilage:

Articular cartilage is the smooth tissue covering the ends of the thighbone, shinbone, and back of the kneecap. It allows the joint surfaces to glide and helps distribute force.
Meniscal cartilage forms two firm, wedge-shaped cushions—the medial and lateral menisci—between the thighbone and shinbone. The menisci help absorb shock and stabilize the knee.

Either type can be injured. Articular cartilage may develop a localized defect after trauma or break down gradually as part of osteoarthritis. A meniscus may tear during twisting, pivoting, or deep squatting, although age-related tissue changes can also make it more vulnerable. The National Library of Medicine provides additional information about cartilage disorders and their causes.

Key Signs Your Knee Cartilage May Be Damaged

Possible sign	What you may notice
Pain with activity	Aching or sharper pain while walking, climbing stairs, squatting, running, or standing from a chair.
Swelling	Puffiness around the knee that may develop soon after an injury or increase after activity.
Stiffness	Difficulty moving after sitting, resting, or waking in the morning.
Reduced range of motion	Trouble fully bending or straightening the leg.
Catching or locking	A sensation that something inside the knee is briefly obstructing movement—or an inability to straighten the knee.
Grinding or rough movement	A grating sensation called crepitus, especially during stairs, squats, or rising from a chair.
Instability	The knee feels unreliable, shifts, buckles, or gives way.
Declining function	Activities that were previously comfortable become painful or difficult.

Occasional painless clicking is common and does not necessarily indicate cartilage damage. Clicking is more concerning when it occurs with pain, swelling, locking, instability, or reduced motion.

How the Symptom Pattern Can Offer Clues

A sudden cartilage or meniscus injury often follows a forceful twist, awkward landing, direct impact, or rapid change in direction. Pain may be concentrated along the inner or outer joint line. Swelling can develop, and the knee may catch or become difficult to straighten.

Gradual articular cartilage breakdown more often produces activity-related aching, short-lived stiffness after rest, swelling after heavy use, grinding, and slowly decreasing mobility. The National Institute of Arthritis and Musculoskeletal and Skin Diseases describes pain, stiffness, swelling, limited motion, and instability among the common symptoms of osteoarthritis.

Pain around or behind the kneecap may be aggravated by stairs, squatting, running, or sitting with the knee bent for a long time. This pattern can involve irritation of the joint between the kneecap and thighbone, but it can also occur without a cartilage defect.

Symptoms alone cannot confirm which structure is affected. Health concerns often have overlapping warning signs—just as signs of a damaged skin barrier can resemble other skin conditions. Knee pain may come from cartilage, bone, ligaments, tendons, muscles, bursae, or inflammation within the joint. Different forms of arthritis can also cause knee pain and swelling.

How Knee Cartilage Problems Are Evaluated

A healthcare professional will usually ask when the symptoms began, whether there was an injury, which movements cause pain, and whether the knee locks or gives way. The physical examination may assess swelling, tenderness, alignment, walking pattern, stability, strength, and range of motion.

Testing depends on the suspected cause:

X-rays cannot show cartilage directly, but they can reveal fractures, bone spurs, alignment problems, or reduced space between bones associated with cartilage loss.
MRI provides detailed images of soft tissues and may identify injuries involving articular cartilage, the menisci, ligaments, or nearby bone.
Joint-fluid testing may be considered when infection, gout, or another inflammatory condition is possible.

An MRI is not necessary for every sore knee. Clinicians generally choose imaging based on the examination, symptom duration, injury mechanism, and whether the result is likely to change treatment. Learn more about why a clinician may order a knee MRI scan.

What to Do While Waiting for an Evaluation

If symptoms are mild and there was no major injury, temporarily reduce activities that provoke pain—particularly forceful twisting, deep squatting, jumping, or high-impact exercise. A cold pack wrapped in cloth may help with recent swelling. Elevating the leg and using light compression may also provide short-term comfort, provided the compression is not tight enough to cause numbness, tingling, or color changes.

Gentle, comfortable movement is usually preferable to keeping the knee completely still for an extended period. However, do not push through sharp pain, locking, or repeated buckling. A primary care clinician, sports medicine physician, orthopedist, or physical therapist can help identify appropriate strengthening and mobility exercises.

Treatment depends on the type and extent of the problem. Options may include activity modification, physical therapy, weight management when relevant, bracing, symptom-relieving medication, injections, or surgery. Cartilage damage does not automatically mean an operation is required, and treatment decisions should account for symptoms and daily function—not imaging findings alone.

When to Seek Care

Arrange a medical evaluation if knee pain or swelling persists, repeatedly returns, disrupts sleep, limits work or exercise, or makes routine activities increasingly difficult. Prompt assessment is also appropriate after a significant twist, fall, collision, or other injury.

Seek urgent care when:

You cannot put weight on the leg.
The knee looks deformed or moved out of position.
Swelling develops rapidly after an injury.
The knee is locked and cannot fully bend or straighten.
The knee is hot, red, and very swollen, especially with fever or feeling ill.
You develop numbness, tingling, unusual discoloration, or coldness below the knee.
Pain is severe or the knee repeatedly collapses beneath you.

These symptoms can indicate a serious injury, blocked joint movement, infection, or another problem requiring timely treatment. A clinician can determine whether damaged cartilage is responsible and recommend care based on the specific diagnosis.