Why your kneecap might be grinding against your thighbone
In short: It often starts as a dull ache during a run or after a long flight. Known as runner's knee, Patellofemoral Pain Syndrome occurs when the kneecap fails to glide smoothly, causing friction and discomfort that can disrupt even the most dedicated athletes.
Patellofemoral Pain Syndrome (PFPS) is an overuse disorder characterized by pain in the front of the knee, specifically around or behind the patella. This discomfort typically arises when the kneecap rubs against the femur, the lower end of the thighbone. While it is frequently associated with running and jumping, the condition is not caused by other specific pathologies like meniscus tears, tendonitis, or bursitis.
The mechanics of the pain are often tied to alignment and muscle balance. Structural defects, malalignment of the kneecap, or muscles that do not keep the patella in line—such as weak thigh muscles or tight hamstrings and Achilles tendons—can contribute to the friction. Factors like walking with feet rolling inward or moving the knee inward during a squat are also linked to the syndrome. Interestingly, biological differences play a role: females are twice as likely to develop PFPS, potentially because a wider pelvis increases the angle at which the knee bones meet.
Symptoms can manifest as a dull ache, tenderness to the touch, or even audible clicking, grinding, and popping sounds when bending the knee. Pain often intensifies during activities like squatting, kneeling, or climbing stairs, and can even occur after sitting for long periods with bent knees. While simple interventions like rest, ice, and strengthening exercises are common, more complex cases may require physical therapy or medical management to restore proper range of motion and stability.
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Sources
- Summary by Intellect · source: Patellofemoral Pain Syndrome - runner's knee
- Also: Patellofemoral Pain Syndrome (Runner's Knee)
- Also: Patellofemoral pain syndrome - Symptoms and causes
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