ACL and PCL are located within articular surfaces, but outside the synovial lining. I’ve read this somewhere, but I can’t understand how, as I believe that articular cartilage is just attached to the bone while synovial lining is outside of a joint. Also what is the procedure to palpate the ACL and the PCL?

The ACL and PCL are best described as being covered with the synovial membrane (and not outside the synovial lining) thus protecting them from the fluid-filled synovial cavity. The synovial lining is the extremely thin inner, or intima layer of the synovial membrane.

Both cruciate ligaments cannot be palpated in the normal sense as these ligaments are both intra-articular structures located deep within the knee joint cavity. The joint cavity has first to be exposed, for example by injury or surgery, before the ligaments can be ‘palpated’.

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