.i///7<r/..i/7o.\> (>!' mi-: I'UHTKUIOR LIMBS. 



187 



No. 1. 



Fig. 92. 



No. 2. 



j'. 



tlifv will not he detailed hero; but some remarks will lie made with 



t the displacement the fibro-cartilages undergo when tlie articulation is in 



motion. 



During ./Z&nbn and extension, these bodies, fixed on the tibial facets, which 

 they transform into glenoid cavities, 

 move with them on the condyles of the 

 femur, from before to behind, or behind 

 to before, according to the movement 

 evented. But at the same time they 

 also glide in an inverse direction, and 

 to a very appreciable degree, on the 

 superior extremity of the tibia. There- 

 tore, during flexion, they pass from 

 behind forward on this extremity, and 

 are drawn backwards during exten- 

 sion. 



In rotation, which may take place 

 from within to without, or from with- 

 out to within, the movement is pro- 

 duced not only by the pivoting of the 

 condyles in their glenoid cavities, but 

 also by a sensible displacement of the 

 meuiscii on the tibial surfaces. 



In tho Dog and Cat, the meuiscii are 

 joined together near their anterior insertion 

 oy a transverse fibrous band. There is only 

 one patellar ligament, and the posterior liga- 

 ment shows in its thickness two email sesa- 

 inoid bones against which the condyles of 

 the femur play inwardly, and which give 

 attachment, outwardly, to the original ing LIGAMENTS ATTACHING THE THREE i 

 branches of the external gastrocncmius mus- OF THE 1.1 .<,. 



el.-. '11, i re i.- ii" 1 inoM-nat. liar eap.Mile, and No l Posterior face. No. 2. Anterior face. 

 ..nly one syuovial membrane for the whole _ 1? Complementary fibro-cartilaginous 

 articulati" i. 



In the /'/;/ and Sheep, there is also only 

 one ligament and one synovia! capsule. 



4. Tibio-fibular Articulation. 



This articulation represents a small 

 planiform diarthrosis, whose move- 

 ments are very limited and obscure. 

 It is formed by the union of tho irre- 

 gular diarthrodial facet which occupies 

 the internal face of tho head of tho 

 fibula, with the analogous facet on tho 

 external superior tuberosity of tho 

 tibia. Short and strong interosseous 

 or peripheral fibres envelop these 

 on every side, and maintain them 



pad of the patellar surface; _', Kxternal 

 patellar ligament ; 2', Insertion of the long 

 vastus into this ligament; H, Internal 

 patellar ligament; 3', Its upper insertion 

 tran -formed into a complementary appa- 

 ratus of the patellar surface; 4. Middle 

 patellar ligament; '., Kxtenial meniscus 

 of the tibia; 6, Its l.randi of insertion 

 into the femur cut oft' at its origin: 7, Its 

 |M.sterior til.ial insertion; 8, External me- 

 niscus; '.', Insertion of tlie anterior crucial 

 at into the fosxi t> f the tibial >pine; 

 lo, Tjlijal insertion of the posterior crucial 

 ligament ; 11, Inferior insertion of the ex- 

 ternal femon.-til.ial ligament; 1 _', \.\, 14, 



mu cle; c, Surface of insertion to, the 

 ]>erforau8 muncle. 



linnly in contact. 



'lln fibula is also attached to the tibia: " 1, Above, by two small liga- 

 nientdus fasciculi crossed like the letter X, which form tho superior part of 

 the great ureh through which pass tho anterior tibial artery and vein ( I-'iir. 



i -) ; 2, In tho middle, by a kind of aponeurotic membrane, whoso width 



