KNEE JOINT. 



161 



Fig. 93 * 



is covered in by the tendon of the biceps, and has passing beneath it the 

 tendon of origin of the popliteus muscle, and the inferior external articular 

 artery. 



The true ligaments within the joint are the crucial, 

 transverse, and coronary. 



The anterior, or external crucial ligament, arises 

 from the depression upon the head of the tibia in front 

 of the spinous process, and passes upwards and back- 

 wards to be inserted into the inner surface of the outer 

 condyle of the femur, as far as its posterior border. 

 It is smaller than the posterior. 



The posterior, or internal crucial ligament, arises 

 from the depression upon the head of the tibia, behind 

 the spinous process, and passes upwards and forwards 

 to be inserted into the inner condyle of the femur. 

 This ligament is less oblique and larger than the an- 

 terior. 



The transverse ligament is a small slip of fibres 

 which extends transversely from the external semilunar fibro-cartilage, 

 near its anterior extremity, to the anterior convexity of the internal 

 cartilage. 



The coronary ligaments are the short fibres by which the convex bor- 

 ders of the semilunar cartilages are connected to the head of the tibia, and 

 to the ligaments surrounding the joint. 



The semilunar fibro-cartilages are two falciform plates of fibro-cartilage, 

 situated around the margin of the head of the tibia, and serving to deepen 

 the surface of articulation for the condyles of the femur. They are thick 

 along their convex border, and thin and sharp along the concave edge. 



The internal semilunar fibro-cartilage forms an oval 

 cup for the reception of the internal condyle ; it is 

 connected by its convex border to the head of the 

 tibia, and to the internal and posterior ligaments, by 

 means of its coronary ligament ; and by its two ex- 

 tremities is firmly implanted into the depressions in 

 front and behind the spinous process. The external 

 semilunar fibro-cartilage bounds a circular fossa for 

 the external condyle : it is connected by its convex 

 border with the head of the tibia, and to the external 

 and posterior ligaments, by means of its coronary 

 ligament ; by its two extremities it is inserted into 

 the depression between the two projections which 

 constitute the spinous process of the tibia. The two 

 extremities of the external cartilage being inserted 



into the same fossa form almost a complete circle, 







* A posterior view of the ligaments of the knee joint. 1. The fasciculus of the lif-a- 

 mentum posticum Winslowii, which is derived from, 2. the tendon of the semi-mem- 

 branosns muscle ; the latter is cut short. 3. The process of the tendon which spreads 

 out in the fascia of the popliteus muscle. 4. The process which is sent inwards be- 

 neath the internal lateral ligament. 5. The posterior part of the internal lateral liga- 

 ment. 6. The long external lateral ligament. 7. The short external lateral ligament, 

 8. The tendon of the popliteus muscle cut short. 9. The posterior superior tibio-fibular 

 igament. 



j- The right knee joint laid open from the front, in order to show the internal liga 

 14* L 



Fig. 94.f 



