THE KNEE JOINT 



413 



Besides the cdmmon ligaments, there are seven proper to this joint — three 

 anterior, two posterior, and two interosseous. 



Of the three a7iterio7- ligaments, the external one, covered by the external 

 lateral ligament, unites the unciform bone to the outer small metacarpal 

 bone. The middle one unites the os magnum to the large metacarpal bone. 

 The internal one unites the trapezoid to the inner small metacarpal bone. 



Fio. 4S.— Back View of Left 



Knee Joint, seen oblique- 

 ly FROM THE Right, and 

 showing the deep-seated 

 Ligaments. 



A. Inferior third of radius. 



B. Pisiform bone. 



C. External small metacarpal 



bone. 



D. Internal small metacarpal 



bone. 



1. External lateral ligament. 



2. 3. Scapho - metacarpal liga- 



ment. 



4. Radio-lunar ligament. 



b. Ligament between the pisi- 

 iform, unciform, and ex- 

 ternal small metacarpal 

 boiie. 



Fig. 49. — Baok View op 

 Right Knee Joint, show- 

 ing the superficial Liga- 

 ments. 



A. Inferior third of radius. 



B. Superior third of large 



metacarpal bone. 



C. Internal small metacarpus. 



D. External small metaearxal 



bone. 



1. Internal lateral ligament. 



2. External lateral ligament. 



3. Ligament between the ra- 



dius, lunar, and pisi- 

 form bones. 



4. 5. Ligament between the 



unciform, pisiform, 

 and between the ex- 

 ternal small metacar- 

 pal bones. 



6. Strong band of ligamentous 



fibres, binding down 

 the flexor tendons in 

 their sheath or groove. 



7. 7. Groove for the passage 



of the porforans and 

 perforatus tendons. 



The tivo posterior ligaments, described by Rigot, are very difficult of 

 demonstration, being only with the greatest care separated from the common 

 posterior ligament. One of them, however, is capable of being made out 

 by dissection, as a strong band of fibres passing from the back of the 

 scaphoid bone to the inner small metacarpal bone (see o 3, Eig. 48). 



The tivo interosseous ligaments ascend from the roughened depressions 

 existing between the three metacarpal bones to the interosseous ligaments 

 of the second row. 



