Tangled twins present a puzzle as to which legs belong to which head. The feet that do not belong to the head will need to be repelled to make room for the lamb with head already in the birth canal to be extracted first. A hindleg can be differentiated from a front leg by palpating the presence of one joint, the pastern below the hock, which feels similar to the point of th elbow. In case of a front leg, there are two joints below the point of the elbow, the carpus and the pastern.
Smith MC (2006)