ABNORMAL CONDITIONS OF THE SHOULDER JOINT. 



601 



the fragment between the finger and thumb, 

 and prove at once the mobility of the frag- 

 ment and the existence of crepitus. 



If, says Boyer, the soft parts were in the 

 natural state, we could easily recognise the 

 fracture of the coracoid process, when it has 

 occurred ; but so much force is necessary to 

 produce this fracture, that the considerable 

 swelling which always accompanies it, prevents 

 us from being able to recognise the characters 

 of the injury, so that it is not generally as- 

 certained except in the dead body. 



C. Fracture of the neck of the scapula. 

 By a fracture of the neck of the scapula is 

 meant a fracture through the narrow part of 

 the bone immediately beneath the notch on 

 the coracoid margin of the scapula, by which 

 the glenoid or articular portion of the bone, 

 together with the coracoid process, becomes 

 detached from the rest of the scapula ; the 

 head of the humerus falls into the axilla, with 

 the glenoid cavity attached to it by means 

 of the capsular ligament. 



Sir Astley Cooper says the diagnostic marks 

 of this injury are three : first, the facility with 

 which the parts are replaced ; secondly, the 

 immediate fall of the head of the bone into 

 the axilla when the extension is removed ; 

 and thirdly, the crepitus which is felt at the 

 extremity of the coracoid process when the 

 arm is rotated. The best method for dis- 

 covering the crepitus is as follows ; let the 

 surgeon's hand be placed over the top of the 

 shoulder, and the point of his forefinger be 

 rested on the coracoid process ; the arm being 

 then rotated, the crepitus is distinctly per- 

 ceived, because the coracoid process being 

 attached to the glenoid cavity, and being 

 broken off with it, although itself uninjured, 

 crepitus is communicated through the medium 

 of that process. We believe this accident to 

 be exceedingly rare. 



D. Fracture of the superior extremity of the 

 humerus. The superior extremity of the 

 humerus may be broken across, in the line of 

 its anatomical neck, or through the head of 

 the bone above this oblique line. In both 

 cases the fracture will be intra-capsular. 



Secondly, the fracture may be extra-cap- 

 sular, passing through the tubercles ; beneath 

 the anatomical neck of the humerus, yet above 

 the line of the junction of the epiphysis, with 

 the shaft of the bone. 



Thirdly, a fracture may traverse the hu- 

 merus in the line of junction of the epi- 

 physis with the shaft of this bone, or close to 

 this line.* 



Fourthly, the humerus may be fractured in 

 the part called the surgical neck, beneath the 

 line of junction of the epiphysis with the 

 shaft. 



1. Intracapsular fracture of the humerus. 

 We find on record fractures of the head of 

 the humerus, which were altogether intra- 



* Dr. K. Smith has exposed well the error of con- 

 founding together as the same the line of the ana- 

 tomical neck of the humerus, and the line by which 

 the superior epiphysis is united with the shaft of the 

 bone. 



articular ; and in these cases the head of the 

 bone was separated at the proper anatomical 

 neck. Boyer states he has met with many 

 such cases, most of which were fatal from 

 the severity of the injuries which accompanied 

 the fracture. He mentions the case of a 

 woman who lived for seven days, after having 

 received one of these severe injuries. On 

 making a post-mortem examination of the 

 shoulder, the separated head of the humerus 

 had suffered a great loss of substance; it was 

 hollowed out as to its fractured surface, so as 

 to represent a complete hollow cap or " ca- 

 lotte." It seems to be the opinion of many, 

 that in cases of intra-capsular fractures of the 

 superior extremity of the humerus, unless 

 some portions of synovial membrane and 

 periosteum remain unbroken, no bony consoli- 

 dation can occur. This may be true as to 

 some fractures ; but, on the other hand, we 

 have evidence of cases in which the head 

 of the humerus must have been completely 

 broken, as well as all its membranous cover- 

 ings severed ; and yet perfect reunion of 

 the portion of bone which had been detached 

 was established ; but in these cases it is to be 

 observed, that impaction, to a certain degree, 

 of the head of the humerus into the shaft, 

 had occurred. 



The possibility of the consolidation, by 

 bony union of a fracture of the anatomical 

 neck of the humerus had been long doubted. 

 Upon this subject, J. Cloquet observes : " I 

 have, some years ago, made known a case of 

 fracture of the humerus through its anatomi- 

 cal neck, which had been perfectly united. 

 Re'ichel had before published a similar fact : 

 sometimes the consolidation in these cases 

 would appear to be accomplished by the agency 

 of the inferior fragment, from which spring 

 up stalactiform productions, which surround 

 and encase the superior fragment." He adds, 

 " we have also met with examples, in which 

 consolidation did not take place. In these 

 last cases, the head of the bone has been 

 found to have been hollowed out, by contact 

 with the inferior fragment, so that a false 

 joint had been formed in the situation of the 

 fracture; and the superior fragment, by its 

 inferior surface, represented a hollow cup, or 

 * calotte articulaire.'"* 



The following cases will show that a frac- 

 ture through the anatomical neck of the hu- 

 merus may occur, in which the head of the 

 bone may be subsequently impacted into the 

 shaft, and be then consolidated by bony union. 

 A female, set. 47, was admitted into the 

 Richmond Hospital, under the care of the 

 late Dr. Macdowell, for an injury of the hu- 

 merus, the result of a fall upon the shoulder. 

 The case has been merely entered in the 

 Hospital Case-Book, " a fracture of the 

 humerus." Five years afterwards, the wo- 

 man was admitted into the same hospital, 

 under the care of Mr. Adams, for another in- 

 jury, a fracture of the thigh, of which she 

 died. Post mortem, the shoulder was care- 



* Cloquet, Dictionnaire de Medicine, article FRAC- 

 TURE. 



