STIFLE JOINT. 



147 



At its patellar attachment, the internal straight ligament becomes 

 enlarged, and fibro-cartilaginous in structure, projecting over the 

 edge of the femoral trochlea, and thus enlarging the articular 

 surface of the patella, 



Femoro-tihial Group. — There are two crescentic fibro-carti- 

 laginous discs, the semilunar cartilages or 

 menisci, interposed between the condyles of 

 the femur, and the head of the tibia, the 

 internal one being the larger and thinner. 

 Their internal borders are sharp and con- 

 cave, embracing the tibial spine, while the 

 external are thick and convex. Their super- 

 ior surfaces are hollowed for the reception 

 of the femoral condyles, while the inferior 

 are smooth and flat, resting on the tibia. 

 Their extremities terminate in the coronanj 

 ligaments, which attach them to the bones ; 

 these are five in number, two for the i^iter- 

 nal disc, an anterior one attaching it to an 

 excavation in front of, while the posterior 

 one is fixed to a furrow behind, the tibial 

 spine. The external disc has three, one 

 fixed in front of the tibial spine, and tivo 

 behind it, of which the superior one is 

 longer and stronger, being inserted in the 

 intercondyloid notch of the femur, while the 

 inferior is thin and flat, and fixed to the 

 head of the tibia. 



Crucial or Interosseous Ligaments. — 

 These, anterior and posterior, are very 

 strong, and are situated between the con- 

 dyles of the femur. The anterior or exter- 

 nal stretches obliquely forwards, and is 

 attached in the intercondyloid notch inside 

 the external condyle of the femur, and to 

 a depression on the summit of the tibial 

 spine. The iwsterior or internal, the longer, arising anteriorly 

 inside the internal condyle, crosses the anterior ligament, and is 

 attached posteriorly to a small eminence behind the inner articu- 

 lar surface of the head of the tibia. 



Lateral Ligaments. — The external one, the shorter and stronger. 



Fig. 63. 

 ligaments of the stifle joint 

 — posterior aspect, o, Exter- 

 nal lateral patellar ligament ; 

 h, External lateral femoro- 

 tibial ligament ; c, Posterior 

 crucial ligament ; d, External 

 meniscus ; e, Internal menis- 

 cus ;/, Femoral coronary liga- 

 ment ; (J, Posterior external 

 coronary ligament ; h, Fibulo- 

 tibial ligament. 



