THE SCAPULA. 



201 



LONG HEAD 

 OF TRICEPS 



GROOVE FOR CIRCUM- 

 FLEX SCAPULAR 

 ARTERY 



The body of the bone, which is thin and translucent, except along its margins 

 j nd where the spine springs from it, has three margins and three angles. Of these 

 I Margins the vertebral (margo vertebralis) is the longest; it stretches from the 

 j ledial angle above to the inferior angle below. Of curved or somewhat irregular 

 ;| utline, it affords a narrow surface for the insertion of the leva tor scapulae, rhom- 

 inoideus minor, and rhomboideus major muscles. 



The superior margin, which is thin and sharp, is the shortest of the three. It 

 uns from the medial angle towards the root of the coracoid process, before 

 I eaching which, however, it is interrupted by the scapular notch, which lies very 

 i.i lose to the medial side of the base of that process. This notch, which is converted 

 Into a foramen by a ligament, 

 Jin occasionally by a spicule 

 . if bone, transmits the supra- 

 ,;capular nerve, whilst the 

 I rans verse scapular artery 

 | uns above it. Attached to 

 {he superior margin, close to 

 U he notch, is the posterior belly 

 I f the omo-hyoid. The axillary 

 i. nargin, so called from its rela- 

 i ion to the hollow of the axilla 

 jj armpit), is much stouter than 

 dther of the others ; it ex- 

 pends from the lateral angle 

 libove to the inferior angle 

 | )elow. The upper inch or so 

 | >f this border, which lies im- 

 mediately below the glenoid 

 Articular cavity, is rough and 

 ubercular (tuberositas infra- 

 rlenoidalis), and affords at- 

 tachment to the long head of 

 he triceps. Below this it is 

 usually crossed by a groove 

 jvhich marks the position of 

 i he circumflex scapular artery. 



The medial angle is sharp 



ind more or less rectangular ; 



Lhe inferior angle is blunter 



Lnd more acute; whilst the 



lateral angle corresponds to 



hat part of the bone which 



3 sometimes called the head, 



md which supports the glenoid cavity and the coracoid process. 



The glenoid cavity is a piriform articular area, slightly concave from above down- 

 vards and from side to side ; its border is but slightly raised above the general surface 

 | md affords attachment in the recent condition to the labrum glenoidale, which helps 

 o deepen the socket in which the head of the humerus rests. Below, the margin 

 >f the glenoid cavity is confluent with the infra-glenoidal tuberosity, whilst, above, 

 It blends with a tubercle (tuberositas supraglenoidalis), to which the long head 

 )f the biceps muscle is attached. Springing from the upper part of the head, 

 jn line with the superior margin, is the processus coracoideus (coracoid process). 

 The base of this is limited laterally by the glenoid edge, whilst medially it 

 s separated from the superior margin by the scapular notch. Eising upwards 

 or a short space, it bends on itself at nearly a right angle, and ends in a process 

 ; ;vhich is directed laterally and slightly forwards, overhanging the glenoid cavity 

 ibove and in front. Compressed from above downwards, it has attached to 

 : ts upper surface near its angle the conoid ligament, lateral to which there is a rough 

 irea for the trapezoid ligament. Attached to its dorsal border is the coraco- 



SCAPULAR SLIP OF LATISSIMUS 

 DORSI 



FIG. 190. THE DORSAL SURFACE OF THE RIGHT SCAPULA 

 WITH THE ATTACHMENTS OF THE MUSCLES MAPPED OUT. 



