Reference for Chullin 151:8
בשלמא לדידי דאמינא כנגדו בגמל ניכר היינו דקתני
<big><b>GEMARA: </b></big>Rab Judah said in the name of Rab who reported it in the name of R'Hiyya, BELOW means below the joint, and ABOVE means above the joint, and the joint referred to is the joint which is sold together with the head.<span class="x" onmousemove="('comment',' The term used in the Mishnah means 'joint', there is however a difference of opinion in the Gemara as to which joint is intended. It must be remembered that the hind limb is made up of four divisions of bones. First there is the hip, the skeleton of which is formed by the ,hkye lrh ,hkue vbuhkgv vcufrt innominate bones () ; then the thigh, formed by the femur ( or) and patella ( the knee-joint) ; then the leg, eua formed by the tibia () and the fibula (in the ox it is very rudimentary and is represented by a fibrous cord only) ; and finally the hind foot atrv og ,rfnbv vcufrt which corresponds to the human foot and consists of the tarsus () , metatarsus and four digits. The tendons of the muscles behind the tibia are combined into one, termed the 'Achilles Tendon', and are attached to the heel or tuber calcis; this is what is meant ihshdv ,num vcufrt by 'the juncture of the tendons' or . According to Rab Judah the of our Mishnah is the hind foot, all that part below the tarsus, which is usually sold with the head as offal; v. Diagram at end of Tractate.');"><sup>5</sup></span>