158 OSTEOLOGY. 



the removal of calculi from the bladder, and as determining the direction in 

 which instruments should be used in operations upon the pelvic viscera. 



Differences between the Male and Female Pelvis. In the male, the bones are 

 thicker and stronger, and the muscular eminences and impressions on their sur- 

 faces more strongly marked. The male pelvis is altogether more massive ; its 

 cavity is deeper and narrower, and the obturator foramina of larger size. In the 

 female, the bones are lighter and more expanded, the muscular impressions on 

 their surfaces are only slightly marked, and the pelvis generally is less massive in 

 structure. The iliac fossa3 are broad, and the spines of the ilia widely separated ; 

 hence the great prominence of the hips. The inlet and the outlet are larger ; the 

 cavity is more capacious, and the spines of the ischia project less into it. The 

 promontory is less projecting, the sacrum wider and less curved, 1 and the coccyx 

 more movable. The arch of the pubes is wider, and its edges more everted. 

 The.tuberosities of the ischia and the acetabula are wider apart. 



In the foetus, and for several years after birth, the pelvis is small in proportion 

 to that of the adult. The cavity is deep, and the projection of the sacro- vertebral 

 angle less marked. The antero-posterior and transverse diameters are nearly 

 equal. About puberty, the pelvis in both sexes presents the general characters 

 of the adult male pelvis, but after puberty it acquires the sexual characters pecu- 

 liar to it in adult life. 



OF THE THIGH. 



The thigh is formed of a single bone, the femur. 



THE FEMUR. 



The Femur is the longest, largest, and strongest bone in the skeleton, and almost 

 perfectly cylindrical in the greater part of its extent. In the erect posture, it is 

 not vertical, being separated from its fellow above by a considerable interval 

 which corresponds to the entire breadth of the pelvis, but gradually inclines 

 downwards and inwards, so as to approach its fellow towards its lower part, for 

 the purpose of bringing the knee-joint near the line of gravity of the body. The 

 degree of this inclination varies in different persons, and is greater in the female 

 than in the male, on account of the greater breadth of the pelvis. The femur, 

 like other long bones, is divisible into a shaft, and two extremities. 



The Upper Extremity presents for examination a head, a neck, and the greater 

 and lesser trochanters. 



The head, which is globular, and forms rather more than a hemisphere, is di- 

 rected upwards, inwards, and a little forwards, the greater part of its convexity 

 being above and in front. Its surface is smooth, coated with cartilage in the 

 recent state, and presents, a little behind and below its centre, an ovoid depression, 

 for the attachment of the ligamentum teres. The neck is a flattened pyramidal 

 process of bone, which connects the head with the shaft. It varies in length and 

 obliquity at various periods of life, and under different circumstances. Before 

 puberty, it is directed obliquely, so as to form a gentle curve from the axis of the 

 shaft. In the adult male, it forms an obtuse angle with the shaft, being directed 

 upwards, inwards, and a little forwards. In the female, it approaches more nearly 

 a right angle. Occasionally, in very old subjects, and more especially in those 

 greatly debilitated, its direction becomes horizontal, so that the head sinks below 

 the level of the trochanter, and its length diminishes to such a degree, that the 

 head becomes almost contiguous with the shaft. The neck is flattened from before 

 backwards, contracted in the middle, and broader at its outer extremity, where it 



1 It is not unusual to find the sacrum in the female presenting a considerable curve extending 

 throughout its whole length. 



