WRIST-JOINT (ABNORMAL ANATOMY). 



J528 



and lunar bones, which confronted each other, 

 were covered with an ivory-like polish. The 

 trapezium, where it supported the first phalanx 

 of the thumb, was polished on its pulley-like 

 articular surface. The trapezoides was much 

 diminished in size, and solidly anchylosed with 

 the first phalanx of the index finger. The 

 transverse diameter of the magnum was not 

 one quarter of an inch ; and the loss of breadth 

 to this degree accounted somewhat for the 

 abnormal narrowing of the carpus already 

 noticed. The cuneiform was normal, as well 

 as the pisiform. The junction, then, of the 

 magnum with the scaphoid, and the equally 

 solid bony union of the trapezoides with the 

 meta-curpal bone of the index finger, were the 

 only articulations of this region, or, indeed, of 

 the whole skeleton of this individual, which 

 presented specimens of true bony anchylosis. 

 The cause of the eburnation of the surfaces 

 of some of the carpal bones might have been 

 that these bones bore occasionally much of 

 the weight of the man in progression, because 

 he had been much disabled in his lower limbs, 

 and habitually used crutches. 



Synovial Tumours of the Region of the Wrist. 

 Synovial tumours generally present them- 

 selves around the joints of the extremities ; 

 and the wrist seems especially liable to them. 

 By the term synovial tumours of the wrist, we 

 do not mean those formed by an increased 

 effusion into the proper synovial sac of the 

 radio-carpal articulation, but enlargements 

 constituted by bursae in this region. 



Synovial cysts, called ganglions, are fre- 

 quently seen on the back of the wrist and 

 carpus. They are of a globular form, and, as 

 to size, vary from that of a hazel-nut to that 

 of a walnut. They are usually situated at the 

 level of the medio-carrjal articulation in the 

 course of the extensor tendons as they pass 

 to the carpus. These tumours are slightly 

 moveable, indolent, and painless, without any 

 alteration in the colour of the skin which 

 covers them from that which is natural. The 

 contents of these little swellings are found to 

 be synovia of a variable consistency : some- 

 times it is serous and limpid ; occasionally 

 the contents are constituted by a thick trans- 

 parent jelly. The cyst seems to be formed 

 by the reticular tissue which immediately 

 covers the sheath of the extensor tendons. 

 The part of the cyst which corresponds to 

 the skin is united to it by a layer of very thin 

 cellular tissue, but loose enough to allow of 

 the skin being easily raised up. The part, on 

 the contrary, which is deeply situated reposes 

 in the sheath of the tendons, or the capsular 

 ligament of the wrist, and is firmly connected 

 to them. This union is sometimes so inti- 

 mate that it is impossible to take away the 

 cyst without interfering with the tendon or 

 the articular capsule. 



The thickness of this cyst varies much. 

 Sometimes it is thin and translucent, and it 

 breaks when subjected to but little pressure ; 

 at other times its thickness and its texture are 

 such that the most violent efforts cannot rup- 

 ture it. 



We have usually seen this disease in fe- 



males more than in males ; and the cause of 

 the origin of these little tumours in the wrists 

 of the iformer appeared to us frequently attri- 

 butable to over-exertion, such as prolonged 

 playing on some musical instruments, such, 

 for example, as the harp or piano. 



Whatever may have been the cause for the 

 origin of these encysted tumours, once formed, 

 they for a time increase in a gradual manner ; 

 and when they have attained a moderate size, 

 they cease to grow. They sometimes, though 

 rarely, subside spontaneously. 



The interior of the membranous sac, m the 

 distention of which, by a glairy fluid, the tu- 

 mour consists, is smooth and polished. The 

 interior of these cysts generally have no com- 

 munication whatever either with the medio- 

 carpal or wrist-joint itself; but Velpeau says 

 he has seen two cases in which he could 

 easily press the liquid contained in the cyst 

 into the articulation of the wrist if he at the 

 same time gave certain movements to the 

 joint. He adds, that twice he had an oppor- 

 tunity, in the dead body, to show that these 

 cysts communicated with the interior of the 

 joint. 



Morbid Condition of the Synovial Bursts of 

 the Flexor Tendons. The swellings which 

 these enlarged bursae constitute, do not pre- 

 sent the same regularity of form that gan- 

 glions do. 



The cause of their origin may generally be 

 referred to some great exertion to a fall or 

 other external violence, I have known, in 

 one case, one of these swellings appear with- 

 out having been produced by any injury. The 

 constitution of this patient was very decidedly 

 of the rheumatic character. 



The species of swelling we are now refer- 

 ring to commences in the synovial bursa 

 which envelopes the flexor tendons of the 

 fingers as they pass beneath the anterior an- 

 nular ligament of the wrist : the swelling con- 

 sists of an increased quantity of synovial fluid 

 effused into the cavity of the little sac the 

 bursa constitutes. At first the effusion is 

 small, and the bursa keeps within its normal 

 boundary, behind the anterior annular liga- 

 ment ; but the accumulation of synovia in- 

 creases by degrees; and then the swelling 

 appears divided into two parts, which are 

 separated from each other by the annular 

 ligament, which seems to form a transverse 

 band which constricts the sac, leaving a tu- 

 mour above the annular ligament in front of 

 the wrist, and another beneath the level of 

 this ligament in the palm. Pressure on the 

 portion of the sac above makes the synovial 

 fluid pass down into the part of the bursal 

 sac beneath. In these cases the skin pre- 

 serves its colour and normal mobility, the fin- 

 gers become somewhat flexed, and there is 

 some difficulty experienced in fully extending 

 them. The patient suffers no pain, but only 

 complains of a numbness and weakness in the 

 fingers, hand, and wrist. 



On compressing one of the extremities of 

 this tumour (as, for example, that placed 



* Digtionnaire de Medecine, torn. 25, pi. 294. 



