STIFLE JOINT 



423 



fibres which enter into its composition are slightly bent and spiral. The 

 Posterior, longer than the preceding, and oblique, is attached inferiorly 

 to the back part of the pit behind the tibial spine, and superiorly to the 

 fore-part of the inter-condyloid hollow, as well as slightly to the side of the 

 inner condyle of the femur ; its fibres are directed upwards and forwards. 



The 2>osterior ligament, ligamentmn jmsticum, belongs to the class of 

 membranous ligaments ; it is formed of white and yellow fibres, which 

 interlace with one another in different ways, and 

 is pierced by numerous openings for the transit 

 of blood-vessels, etc. It is attached by its superior 

 border beneath the condyles of the femur, and by 

 its inferior to the posterior circumference of the 

 superior tibial surface. Its internal surface em- 

 braces the condyles of the femur, and adheres to 

 the posterior crucial ligament, as well as to the 

 inter-articular semilunar cartilages. 



The transverse ligameiit. — Towards the front 

 of the joint the convex borders of the inter- 

 articular fibro-cartilages are connected together by 

 a transverse band, denominated the transverse 

 ligament. 



Under the head of the capsidar ligament are 

 described certain strong portions of fibrous mem- 

 brane which cover exposed parts of the synovial 

 sac. The first, the longest and strongest, termin- 

 ates in the pit situated on the inter-condyline 

 hollow. The second, thin and flattened, is in- 

 serted upon the external surface of the tibia. 

 The third passes from the outer edge of the patella 

 to the external condyle of the femur (see ,, Figs. 

 57 and 58). The fourth corresponds with this 

 on the inner side of the joint. These are some- 

 times described as independent ligaments. 



2. Ligaments op the patella. The external 

 lateral ligament is the longest and strongest, being 

 a flattened band attached by its inferior extremity 

 to the supero-anterior point of the tuberosity of 

 the tibia, and by its superior to the anterior sur- 

 face of the patella. This ligament is united to 

 the internal ligament by an aponeurotic expansion, which is very resisting. 



The internal ligament of the loatella forms also a flattened band, longer, 

 but not so large as, and thinner than, the preceding. Its inferior extremity 

 is attached to the internal side of the anterior tuberosity of the tibia. Its 

 superior extremity, much thickened, becomes fibro-cartilaginous, and is 

 inserted in the projection on the inner and upper border of the patella. 



The middle ligament, a rounded cord (situated, as its name indicates, 

 between the two preceding ligaments), covers and assists in protecting the 

 synovial capsule in front. 



Movements. — During flexion and extension, which are the chief 

 motions permitted, the semilunar fibro-cartilages which are fixed on the 



Fig. 57.— External View oir the 

 Left Stifle Joint. 



A. Femur. 



B. External condyle of femur. 



C. Trochlea. 



D. Tibia. 



E. Fibula. 



F. Patella. 



1. Strong band of fibres. 



2. External lateral ligament, or 



the cajisular ligament, con- 

 necting the ijatella with 

 the external condyle. 



3. 3. Great ligament of the pa- 



tella. 



4. 4. External ligament of the 



patella. 



5. 5. Semilunar fibro-cartilage. 



