ABNORMAL CONDITIONS OF THE SHOULDER JOINT. 



605 



a distinct crepitus could bs perceived. The 

 head of the bone could be felt in the glenoid 

 cavity, and when the shaft of the humerus was 

 rotated no motion was communicated to the 

 head. On the seventh day after the accident 

 all swelling had subsided, and the appearances 

 noted were as follows : On viewing the 

 shoulder in front, a very remarkable angular 

 projection of bone forwards is observed. This 

 prominence is very near the anterior margin 

 of the deltoid muscle, and near the centre of 

 a line drawn from the scapular end of the 

 clavicle to the margin of the anterior wall of 

 the axilla. This projection is evidently the 

 abrupt termination of the upper extremity of 

 the lower fragment of the humerus ; every 

 movement communicated to the shaft of the 

 bone also moves this projecting point, a little 

 below, and to the outside of which, an indent- 

 ation or slight puckering of the skin is observ- 

 able. This last we can readily suppose has 

 been produced by the lower fragment having 

 perforated the deltoid muscle, and engaged 

 itself in the deeper layer of the integument. 



" On viewing the joint sidewise or in pro- 

 file, the posterior angle of the acromion pro- 

 jects much behind, while the abrupt promi- 

 nence already mentioned, formed by the shaft 

 of the humerus, is very salient in front; so 

 that in this side view, the antero-posterior 

 diameter of the joint is seen to be much in- 

 creased. The long axis of the arm is di- 

 rected from above downwards and backwards, 

 very slightly also outwards. By measurement 

 from the acromion to the external condyle of 

 the humerus, the injured side is found to be 

 a quarter of an inch shorter than the oppo- 

 site. The patient cannot himself perform any 

 of the movements of the shoulder joint, ex- 

 cept that of rotation to a small extent, but 

 can permit the humerus to be freely moved 

 by another. Although crepitus was evident 

 at first, now, seven days having elapsed since 

 the accident, it can no longer be elicited. 



"May Yith. Nearly a month has passed 

 since he received the fall ; he has regained 

 considerable power of motion over the left 

 arm, can even raise his hand to the top of his 

 head. On the 6th of June he left the hospi- 

 tal, being able to use his arm ; the deformity, 

 consisting in the abrupt projection of bone, 

 was somewhat reduced." 



4. Fracture of the surgical neck of the hu- 

 merus below the tubcrosities and original line 

 of junction of the epiphysis with the shaft of 

 the lone. In this case there is much de- 

 formity to be observed. The head and tuber- 

 osities form the superior fragment, which in 

 general remains in its natural situation, while 

 the upper extremity of the lower fragment, 

 which last is constituted by the principal part 

 of the shaft of the humerus, is drawn upwards 

 and forwards under the pectoral muscle. 

 When the arm is grasped at the elbow by the 

 surgeon, and pushed upwards, the upper ex- 

 tremity of the broken shaft of the humerus 

 is made to project at the inner side of the 

 coracoid process of the scapula, and is felt to 

 roll whenever the arm is rotated. 



Fracture of the humerus in its surgical 

 neck occurs at different heights in this bone. 

 The most common situation for the fracture 

 is where the spongy portion of the bone 

 unites with the rest of the shaft ; and here it 

 is that the humerus, considered anatomically, 

 would seem to be the least capable of resist- 

 ing external violence. The direction of the 

 fracture is generally transverse, more rarely 

 is it oblique, and, in this last case, the ob- 

 liquity is generally in a line from without in- 

 wards, and from above downwards, parallel to 

 the line of the anatomical neck of the hu- 

 merus, but below it, and the nature of the 

 displacement is variable. Most frequently 

 the inferior fragment is drawn inwards towards 

 the axilla ; but the inferior fragment has been 

 also observed to be displaced and become 

 prominent in other directions. Desault has 

 seen it thrown backwards ; Dupuytren, Pa- 

 letta, Duret, and others, have seen it raised 

 up, and even perforate the deltoid muscle 

 outwards ; finally, it more frequently still has 

 been observed to become prominent in front 

 towards the coracoid process. 



Mons. Gely has, in the Journal de Chi- 

 rurgie, mentioned a case of fracture of the 

 surgical neck of the humerus, in which the 

 fracture was oblique, the obliquity running 

 parallel with, but below, the anatomical neck 

 of the humerus. The inferior fragment had 

 perforated in front the deltoid muscle, very 

 near to the interstice which separates the 

 deltoid from the pectoral muscle; the arm 

 was shortened an inch. These observations 

 refer to the altered position of the inferior 

 fragment, resulting from a fracture through 

 the part of the humerus called the surgical 

 neck. It is said that usually the superior 

 fragment remains in its normal position in 

 these fractures, but this is not always the 

 case. Malgaigne narrates a case of a man, 

 aged 78, in whom the humerus was fractured 

 transversely in its surgical neck, about an 

 inch and a half above the folds of the axilla. 

 There was an overlapping of the bones; the in- 

 jured arm was consequently one inch and a 

 half shorter than the other. The fracture 

 during life could not be reduced; he died on 

 the twenty-sixth day after the injury. The 

 inferior fragment was drawn inwards and for- 

 wards, and indeed during life had raised up 

 the soft parts towards the union of the del- 

 toid and pectoral muscles, more internally than 

 the situation of the coracoid process; the over- 

 lapping of the fragments was to the amount 

 already mentioned. The fracture through the 

 humerus was beneath the tuberosities, the 

 longitudinal axis of the lower fragment was 

 in the direction upwards and inwards, and 

 the longitudinal axis of the upper fragment 

 was directed downwards and outwards. In 

 a word, the superior fragment was in a posi- 

 tion which would correspond to the highest 

 elevation of the arm in the normal state ; and 

 the inferior, on the contrary, was in a position 

 which corresponded to its greatest depres- 

 sion. 



DISLOCATIONS. The head of the humerus 



