SHOULDER-JOINT 123 



the synovial stratum (Fig. 53). This cannot be seen until 

 the capsule has been opened. 



The fibrous stratum of the capsule is not complete at all 

 points. Its continuity is always broken by two and some- 

 times by three or four apertures, and where the lateral margin 

 of the fibrous stratum is attached to the transverse ligament 

 of the humerus there is an aperture below the margin. 

 Prolongations of the synovial stratum are protruded through 



Capsula articularis 



Transverse 



humeral - 



ligament 



Tuberculum 



minus 



Tuberculum 

 majus 



Posterior humeral 

 circumflex vessels 

 and axillary nerve 



"~<^ *- Labrum glenoidale 

 ' 



r^vr---Capsula articularis 

 - r N. axillaris 



^\ Posterior humeral 

 'circumflex vessels 



FIG. 53. Diagram of a Frontal Section of the Right Shoulder 



all the apertures which are present. The largest opening is 

 in the antero- medial part near the root of the coracoid 

 process, and the prolongation of the synovial stratum which 

 passes through it forms the subscapular bursa, which separates 

 the subscapularis from the front of the capsule and from the 

 front of the neck of the scapula. The dissector should note 

 carefully the size and the position of this opening because 

 the head of the humerus is occasionally driven through it, 

 instead of through the lower part of the capsule, when the 

 joint is dislocated. 



