" On viewing the joint sidewise or in pro file, the posterior angle of the acromion pro jects niuch 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 17th. —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 Gth 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 tuberosities and original line of junction of the epiphysis with the shaft of the Ione. —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, Fa 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 huinerus 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 pos! 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.