ABNORMAL CONDITIONS OF THE SHOULDER JOINT. 



613 



was very manifest. The arm was placed close 

 to the side, was neither lengthened nor short- 

 ened ; he had no pain in the shoulder joint, 

 but had very imperfect use of the limb. The 

 shoulder had not the flat appearance externally 

 surmounted by the prominent angle formed 

 by the acromion, which characterises the ax- 

 illary dislocation ; nor had he the fulness be- 

 neath the clavicle and in front of the acromion 

 which are noticed in the dislocation forwards ; 

 on the contrary, a deficiency was observed in 

 front beneath the acromion ; and here the 

 fingers could be sunk into a deep fossa, which 

 seemed to extend even to the unoccupied 

 glenoid cavity ; while behind the posterior 

 angle of the acromion a tumor as large as an 

 orange could be seen and felt (fg. 440.). 

 This rounded prominence moved with the 

 shaft of the humerus ; a well-marked vertical 

 groove showed the distinction between the 

 convexity which belonged to the head of the 

 dislocated humerus behind and that which 

 formed the posterior angle of the acromion 

 (fig. 440.). 



An energetic attempt was made at the 

 Richmond Hospital to reduce the dislocation 

 in this case three months after the accident 

 had occurred, but without success. 



Diagnosis between fractures of the superior 

 extremity of the humerus and dislocations of 

 the shoulder-joint. As we have already pointed 

 out the symptoms which are peculiar to each 

 of the forms of scapulo-humeral dislocations, 

 we may here direct attention to the fact, that 

 these symptoms are very similar to those 

 which belong to fracture of the upper extre- 

 mity of the humerus : so that in many cases 

 the difficulty of distinguishing between these 

 different injuries is such as to lead not un- 

 commonly to a false diagnosis. Every person 

 labouring under either a fracture or luxation 

 of the superior extremity of the humerus, 

 informs us that he has fallen on that side of 

 the body on which the injury exists ; but 

 the position of the arm at the moment of the 

 accident will be found to have been different 

 in the case of fracture and dislocation : so 

 that if we know how the limb was placed at 

 the moment of the fall, we may be led to con- 

 jecture from this alone the nature of the ac- 

 cident which has occurred. If, for example, 

 when the patient is falling, his arm is se- 

 parated from his body directed forwards, or 

 outwards, as it were instinctively to break 

 the fall, and save the upper part of the body, 

 if under these circumstances displacement of 

 the upper part of the humerus occurs, the 

 existing deformity will be found to be the 

 result of dislocation ; but if, on the contrary, 

 the fall takes place when the arm is by the 

 side, as, for instance, in the breeches pocket, 

 and no effort is made by the patient, at the 

 moment of the fall, to raise the arm, the 

 momentum and weight of the body have been 

 received on the point of the shoulder, the 

 resulting injury has been most probably a 

 fracture of the head and upper part of the 

 humerus. In both cases the pain expe- 

 rienced at the shoulder is severe, and gives 



rise to the impression, on the patient's mind, 

 that he fell on that part ; but if the patient 

 has met with a dislocation, it will be found 

 that in reality he has fallen on the palm of 

 the hand, evidences of which the surgeon 

 will be better able to discover in the ex- 

 coriations which the palm has suffered, than 

 by any report which the patient himself may be 

 enabled to make. When the patient has met 

 with a fracture, we shall, on inquiry, discover 

 that the fall has taken place on the outside 

 of the shoulder ; there is, in this case, no 

 abrasion of the palm of the hand, while con- 

 siderable tumefaction and extensive ecchy- 

 mosis, the effects of contusion, are observable 

 along the outer side of the arm. When called 

 to the patient immediately after the accident, 

 we notice those circumstances as to the hand 

 and clothes which will instruct us as to the 

 probability, whether the patient had fallen 

 forwards on the palm of the hand, or com- 

 pletely outwards on the stump of the shoulder. 

 In case of fracture, moreover, there is exten- 

 sive ecchymosis ; in simple dislocation, little, 

 if any; but if it should exist, it is rather on 

 the anterior and internal part of the limb, 

 than on the outside, as in fracture. In both 

 fracture and luxation the acromion is salient, 

 and the deltoid flattened ; but as the dis- 

 placement is more complete in luxation than 

 in fracture, the prominence of the acromion 

 and the depression beneath it are more marked 

 in the former than in the case of fracture. 

 When there is a luxation, and we wish to 

 impart movements to the limb, the humerus 

 often moves in connection with the scapula, 

 as if the two bones made but one body. 

 If there is a fracture, there is abnormal 

 mobility at one point in the upper part of 

 the humerus. This mobility is ordinarily 

 accompanied by a crepitus which is best eli- 

 cited by seiz : ng the inferior extremity of the 

 humerus at the elbow and rotating it on its 

 long axis. 



Finally, great efforts are frequently neces- 

 sary to effect a reduction of the dislocated 

 humerus ; but once replaced, the bone remains 

 in its proper articular cavity, and the de- 

 formity of the shoulder does not recur ; but 

 in fracture, although the bone may be replaced 

 with comparative facility, yet, if it be left un- 

 supported, the deformity will almost imme- 

 diately recur. In the case in which it is not 

 easy to distinguish a fracture from a luxation, 

 Dupuytren gives the precept " Rendez au 

 membre, par des manoeuvres convenables, sa 

 forme et sa longueur naturelles ; retournez 

 aupres du malade sept ou huit heures apres : 

 si vous trouvez 1'epaule deformee, soyez as- 

 sure que vous avez a faire a une fracture." * 



Malgaigne has made the observation, 

 that in all luxations of the head of the hu- 

 merus, the head of the bone must descend 

 below its ordinary level, and consequently 

 that, no matter which of the three disloca- 

 tions has occurred, the dislocated arm must 

 be longer than the other. This appears to us 



es. 



R R 3 



