Belgian doctors have identified a “new” knee ligament in humans, although a French surgeon speculated on its existence as far back as 1879. The anterolateral ligament or ALL, is a narrow band of tissue originating at the lateral femoral epicondyle and traveling obliquely to the anterolateral aspect of the proximal tibia. Researchers think the ALL functions to stabilize the outer part of the knee and prevent it from collapsing inward. When people tear their ACL doctors presume that the ALL is also torn, and that its rupture and subsequent withering may have contributed to its obscurity. There’s still a lot to learn about the ALL as surgeons are now in the initial stages of planning and practicing surgical procedures for treating all tears.
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