Glossary
Medial meniscus
Quick answer
The medial meniscus is the C-shaped rubbery cushion on the inner side of the knee, sitting between the femur and the tibia. It absorbs shock, spreads load and adds stability, and it is torn more often than the outer meniscus, explains Dr. Pablo Gelber, a knee surgeon based at Aman Hospital in Doha.
What it is
The medial meniscus is made of tough fibrocartilage. It is wider at the back (the posterior horn) than at the front, and is firmly attached around its outer rim to the joint capsule and the deep MCL. Only its outer edge has a blood supply, called the red zone; the inner part, the white zone, relies on joint fluid for nutrition.
Why it matters for patients
Because it is less mobile than the lateral meniscus, the medial meniscus is more easily trapped and torn. Younger people usually tear it with a twist under load, often in football, padel or while squatting, and sometimes alongside an ACL tear. In middle age, tears can happen with minor movements as the tissue weakens, such as getting up from a squat or the floor.
Symptoms include pain on the inner joint line, swelling the day after activity, catching or locking, and discomfort with deep bending, kneeling or sitting cross-legged. Tears in the outer, red zone have a better chance of healing after repair. Many degenerative tears improve with physiotherapy, and surgeons aim to preserve as much meniscus as possible because losing it increases the load on the cartilage.
Frequently asked questions
Can a medial meniscus tear heal by itself?
Small tears in the outer, well-supplied rim can settle. Tears in the inner part rarely heal on their own, although many become less painful with time and rehabilitation.
Why does my inner knee hurt when I sit on the floor?
Deep bending squeezes the back of the medial meniscus. Pain on floor sitting or kneeling is a common sign of a tear or irritation there, but examination is needed to confirm it.
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