What does joint congruency mean?

Question

Used in a sentence. The menisci improve the congruency of the articulating surfaces.

Answer 1

It means that the articular surfaces between two bones become more "compatible", making joint movements easier and smoother.
For example, the knee joint has a meniscus between the Femur and the Tibia. Without the meniscus, the two articulating bones would be grating at each other because of the weight these bones carry.

Answer 2

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