513 



the internal intermuscular septum. Its fibres are directed downward and for- 

 ward, and are chiefly attached to an aponturosis which lies on the deep surface of 

 the muscle and is inserted into the inner border of the patella and the Quadriceps 

 extensor tendon, an expansion being sent to the capsule of the knee-joint. Some 

 of the fibres run down by the side of the patella to the condyle of the tibia and 

 are called the retinaculum patellae mediale. 



The Crureus (m. vastus intermedius} arises from the front and outer aspect of 

 the shaft of the femur in its upper two-thirds and from the lower part of the external 

 intermuscular septum. Its fibres end in a superficial aponeurosis, which forms 

 the deep part of the Quadriceps extensor tendon. 



POSTERIOR 



TIBIAL 

 ARTERY 



FIG. 384. Transverse section at the middle of the leg. In front of the interosseous membrane are the ante- 

 rior tibial vessels and nerve; in front of the Soleus, the posterior tibial vessels and nerve; and close to the 

 fibula, the peroneal vessels. (After Braune.) 



Relations. The inner edge of the Crureus is in contact with the anterior edge of the Vastus 

 internus, but when separated from each other, as directed above, the latter muscle is seen merely 

 to overlap the inner aspect of the femoral shaft without taking any fibres of origin from it. The 

 Vastus internus is partly covered by the Rectus femoris and Sartorius, but where these separate 

 near the knee it becomes superficial, and produces a well-marked prominence above the inner 

 aspect of the knee. In the middle third of the thigh it forms the outer wall of Hunter's canal 

 (canali* adductorius [Hunteri]) (Fig. 383), which contains the femoral vessels and the long saph- 

 enous nerve; the roof of the canal is formed by a strong fascia which extends from the Vastus 

 internus to the Adductores longus and magnus. The Crureus is almost completely hidden by 

 the Rectus femoris and Vastus extemus. The deep surface of the two muscles is in relation 

 with the femur and Subcrureus muscles. A synovial bursa (bursa suprapatel/aris) is situated 

 between the femur and the portion of the Quadriceps extensor tendon above the patella; in 

 the adult it communicates with the synovial cavity of the knee-joint. 



The tendons of the different portions of the Quadriceps extensor unite at the lower part of 

 the thigh, so as to form a single strong tendon, which is inserted into the upper part of the patella; 

 some few fibres pass over it to blend with the ligamentum patellae. Strictly speaking, the 

 patella may be regarded as a sesamoid bone, developed in the tendon of the Quadriceps; and 



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