590 



ABNORMAL CONDITIONS OF THE SHOULDER JOINT. 



bicipital groove. It was remarkable that the 

 acromion process and other portions of bone, 



Ftg. 429. 



Case of J. Byrne. Chronic rheumatic arthritis. 



a, line of complete division of the acromion 

 into two portions ; b, coracoid process ; c, acromial 

 end of the clavicle, worn by the attrition of the head 

 of the humerus ; d, tendon of the biceps adherent 

 to the bone ; e, glenoid cavity ; /, capsule widen- 

 ed ; foreign bodies attached to it. 



viz. the outer extremity of the clavicle and 

 coracoid process, had acquired size and density, 

 although their under surfaces were much worn 

 and excavated where they formed an arch 

 which overhung the humerus. These appear- 

 ances showed the great degree of friction and 

 pressure from below upwards which these 

 bones had been subjected to, from the head 

 of the humerus being constantly drawn up- 

 wards by muscular action. We also noticed 

 that the acromion process was traversed from 

 within outwards by a perfect solution of con- 

 tinuity, completely dividing it into two nearly 

 equal portions. This might be supposed by some 

 to have been a fracture which never had been 

 united by bone an opinion which, however, 

 we did not entertain ; the two pieces of the 

 acromion were on a perfect and uniform level, 

 and the edges of the separated portions of 

 bone exhibited no evidence of any ossific de- 

 posit, nor any such appearances as would 

 lead us to infer that a fracture had existed. 



The glenoid cavity of the scapula was 

 larger and deeper, and more of a cup-like form 

 than usual. The cartilage of encrustation 

 and glenoid ligament were removed, the sur- 

 face of the cavity presented a porous appear- 

 ance. Along its inner margin were arranged 

 several round and firm cartilaginous granules. 



The head of the humerus was somewhat 



enlarged. The articular surface had become 

 extended over the superior margin of the 

 greater and lesser tuberosity. Much of the 

 cartilaginous investment of the head of the 

 bone had been removed, and its place supplied 

 by means of a porcelain-like deposit. The line 

 which marks the junction of the head of the 

 bone to the shaft, was studded all round 

 with granular elevations of bone (fig- 429.). 



Our knowledge of the anatomical cha- 

 racters of this disease has now arrived at a 

 degree of precision quite sufficient, we might 

 suppose, to save us henceforth from falling 

 into the error of confounding the morbid re- 

 sults of chronic rheumatic arthritis of the 

 shoulder with the consequences of chronic 

 or acute osteitis, or with the ultimate ef- 

 fects of accidents sustained during the pa- 

 tient's lifetime. Nevertheless we feel called 

 upon now to allude to some cases of partial 

 luxation of the shoulder joint which have 

 been published as the result of accident, but 

 which we consider to be specimens of the 

 chronic rheumatic disease of the shoulder 

 joint which we are endeavouring to describe. 



Among these authors we find Sir A. 

 Cooper, who, in his description of the acci- 

 dent called by him " partial luxation of the 

 shoulder joint, forwards and inwards, to the 

 coracoid process," gives a case which he sup- 

 posed to be one of this accident, and relates 

 the symptoms to teach us how it may be re- 

 cognised ; but for its anatomical characters 

 he refers to an example found in the dissecting 

 room, the history of which was unknown. 

 He says, " The only dissection of this accident 

 which I have had an opportunity of seeing 

 was the following, for which I am indebted to 

 Mr. Patey, surgeon in Dorset Street, who had 

 the subject brought to him for dissection at the 

 anatomical room, St.Thomas's Hospital. The 

 following is Mr. Patey's account : 



" ' Partial dislocation of the head of the os 

 humerus. The head of the os humeri on the 

 left side was placed more forward than is na- 

 tural, and the arm could be drawn no farther 

 from the side than the half way to an hori- 

 zontal position. 



" ' Dissection. The tendons of those muscles 

 which are connected with the joint were not 

 torn, and the capsular ligament was found 

 attached to the coracoid process of the scapula. 

 When the ligament was opened it was found 

 that the head of the os humeri was situated 

 under the coracoid process, which formed the 

 upper part of the new glenoid cavity; the 

 head of the bone appeared to be thrown on 

 the anterior part of the neck of the scapula, 

 which was hollowed, and formed the lower 

 portion of the glenoid cavity. The natural 

 rounded form of the head of the bone was 

 much altered, it having become irregularly 

 oviform, with its long axis from above down- 

 wards : a small portion of the original glenoid 

 cavity remained, but this was rendered irre- 

 gular on its surface by the deposition of 

 cartilage. There were also many particles 

 of cartilaginous matter upon the head of the 

 os humeri, and upon the hollow of the new 



