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MusclesHow does the knee work?
The knee is where the thigh bone meets the shinbone. It works a bit like a door hinge (just a comparison): it bends and straightens. Inside, ligaments hold everything firm and cushions called menisci soften jumps.
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Questions people ask
What is a torn ACL?
It is when the anterior cruciate ligament tears, usually during a sudden twist or stop with the foot planted. People feel a pop, the knee swells and feels unstable. Treatment may be physical therapy or surgery, depending on the case.
What does the meniscus do?
The two menisci absorb shock, help the femur fit onto the tibia and spread the weight over a larger area. When one tears, the knee can hurt, lock or swell.
Why does my knee crack?
Painless cracking is common and usually normal: it can be gas bubbles in the joint fluid or tendons sliding over bone. If the cracking comes with pain, swelling or locking, see a doctor.
What is the kneecap for?
It protects the front of the knee and increases the thigh muscle’s power to straighten the leg, working like a lever (just a comparison). Its official name is the patella.
Sources
This text was written using these references:
- Skeletal System · National Cancer Institute (SEER Training)
This content has not been medically reviewed.