124 THE PRINCIPLES OF MYODYNAMICS. 



in the vicinity of complete flexion — except those 

 of the gastrocnemius and the popUteus : — And 

 when the leg is meeting the thigh at an acute 

 angle, the popliteus and the gastrocnemius will 

 antagonize the ham-string muscles and thus 

 contribute to the stability of the knee-joint : 

 Besides, the tibia, if displaced backward, would 

 soon come against the femur, and so a complete 

 dislocation would be prevented. 



THE FEMUR AND THE HIP-JOINT. 



117. In regard to the hip-joint, the following 

 points are to be noted : (i.) The hip-joint is a 

 ball-and socket joint ; (2.) The socket is deep ; 

 (3.) The head of the femur is two-thirds of a 

 spheroid ; (4.) The average length of the femoral 

 head is about one and two-tenths inches ; (5.) 

 The average length of the femoral neck is about 

 one and four-tenths inches ; (6.) The average 

 lateral diameter of the trochanters at the junc- 

 tion of the femoral neck is about one and five- 

 tenths inches ; (7.) The average distance from 



