ABNORMAL CONDITIONS OF THE SHOULDER JOINT. 



593 



tion, and the deltoid muscle was cut across 

 and thrown back, when the attention of the 

 dissector was attracted by the head of the 

 humerus, which was exposed and firmly sup- 

 ported against the under surface of the acro- 

 mion process by the lips of a vertical rent in 

 the capsular ligament, which was otherwise 

 healthy, firmly girding the anatomical neck of 

 the humerus. The articular cartilage of the 

 head of the humerus had been universally 

 eroded. The head of the humerus had been 

 increased in size by the addition of an osseous 

 margin, which overhung the anatomical neck 

 of the humerus. Several cartilaginous bodies, 

 connected to the surrounding fibrous tissues, 

 projected into the cavity of the joint. The 

 larger were pedunculated and pendulous, 

 while the smaller were attached by broad sur- 

 faces. The articular part of the biceps tendon 

 had disappeared. The capsular ligament was 

 thickened ; and the longitudinal aperture al- 

 ready mentioned, which existed in the upper 

 part, was sufficiently capacious to allow the 

 head of the bone under certain circumstances 

 to pass with facility from its natural situation 

 upwards, and to come in contact with the 

 under surface of the acromion process. The 

 coraco-acromial articulation of the same side, 

 as well as several of the other articulations in 

 this subject, exhibited unquestionable traces 

 of having been affected with the same dis- 

 ease.* 



When a specimen of chronic rheumatic ar- 

 thritis of the shoulder joint, such as the pre- 

 ceding, has been met with, by anatomists not 

 familiar with the ordinary anatomical charac- 

 ters of the disease, it is usually mistaken for 

 a case of partial displacement of the humerus 

 upwards, the result of accident. We find 

 many such cases and such mistakes recorded. 

 Although the history of Mr. Labatt's case was 

 unknown, the appearances which the head of 

 the humerus presented were sufficiently cha- 

 racteristic to clearly designate the true nature 

 of the affection, independently of the condi- 

 tion alluded to of the coraco-clavicular and 

 other articulations, so many concurring cir- 

 cumstances sufficiently proved that, in the 

 above case, the shoulder had been long affected 

 by the chronic rheumatic arthritis, and that 

 this, and not accident, was the source of the 

 partial luxation upwards which existed. 



In April, 1840, Dr. Robert Smith, who is 

 well acquainted with this disease,laid before the 

 Surgical Society of Dublin an account of the 

 post-mortem examination he had made of an 

 aged female, who died of an internal organic 

 disease in the House of Industry. She had 

 been long affected with a partial displacement 

 upwards of the right humerus, which was the 

 result of chronic rheumatic disease. He pre- 

 sented a cast of the upper part of the body, 

 taken after death, showing the degree of ele- 

 vation of the summit of the humerus on the 

 affected side; and also exhibited a prepara- 



* This specimen is preserved in the Museum of 

 the College of Surgeons. Vide Catalogue, Coll. 

 Surg. Ireland, vol. ii. p. 396. 



VOL. IV. 



tion of the shoulder joint to the meeting. The 

 post-mortem examination had been made a 

 few weeks previously to Dr. Smith's com- 

 munication of this case to the society. " It 

 may be seen," he said, " from the cast, that in 

 this case there was a remarkable contrast in 

 the appearance the two shoulder joints pre- 

 sented : on one side, the head of the humerus 

 was placed far above the level of the coracoid 

 and acromion processes. Many persons," he 

 added, " in viewing the cast and accompanying 

 preparation, might consider the specimen as 

 one of some unusual form of congenital mal- 

 formation, or the result of accident ; but the 

 abnormal appearances were clearly the result 

 of that peculiar affection of the joints, of 

 which so many specimens had been elsewhere 

 brought forward by the president in the chair 

 (Mr. Adams), and which disease he has 

 denominated ' chronic rheumatic arthritis.' " 

 Dr. Smith added that his chief reason in 

 bringing forward the case was, that it pre- 

 sented some peculiarities he had not observed 

 in other specimens of the same disease, as it 

 affects the shoulder joint : he had often before 

 noticed the elevation of the head of the bone 

 as a symptom of this affection, but had never 

 seen the elevation to the same degree it had 

 amounted to in this case. The head of the 

 humerus was displaced upwards, even to a 

 point above the level of the clavicle and acro- 

 mion process. The capsular ligament was 

 enlarged, and as thin as if the synovial mem- 

 brane alone constituted it. Superiorly, this 

 capsule was altogether deficient : a large aper- 

 ture was here found, which permitted the head 

 of the humerus to pass upwards, as already 

 mentioned ; the tendon of the biceps was 

 perfect, but was thrown off the head of the 

 bone inwards. The cartilage of the head of 

 the bone was abraded in several places, and 

 osseous depositions had been formed in the 

 vicinity of the bicipital groove, and around the 

 margin of the articular head of the humerus, 

 as is usually the case in examples of chronic 

 rheumatic disease. Mr. Smith observed, 

 that the preparation showed a large deficiency 

 in the upper part of the capsular ligament a 

 fact not before observed by him, until he had 

 seen Mr. Labatt's preparation ; and even then 

 he was disposed to attribute the deficiency to 

 some injury received in removing the parts. 

 He had therefore taken the greatest care in 

 removing the preparation just exhibited to the 

 society, and had found that in dividing the 

 deltoid muscle he had cut at once into the 

 cavity of the joint. 



Dr. Smith and the writer have lately care- 

 fully examined this preparation, and find that 

 the acromion process has been much reduced 

 in thickness ; its under surface is excavated, 

 and denuded of all periosteal covering ; this 

 process is divided into two portions, as if a 

 fracture had traversed the original line of the 

 junction of the epiphysis with the rest of 

 the process : half an inch in extent of the bone 

 is thus separated from the rest, and seems 

 merely retained by a ligamentous connection. 



The deltoid and triangular ligament were 



QQ 



