This is a kind of knot used by surgeons when suturing (sewing) a torn meniscus. The knot resembles a tiny mulberry on the surface of the meniscus.
Tying the mulberry knot
The surgeon introduces the suture via a wide-bore needle pushed through the tear in the meniscus from the outside-in, and the suture is retrieved from inside the joint, pulled out via the arthroscopy portal, and a knot is tied. The suture is then pulled back into the joint and the knot pulled firmly to close the two ends of the tear. The other side of the suture is secured outside the capsule.
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