ABNORMAL CONDITIONS OF THE KNEE-JOINT. 



Fig. 2. Fi - 3 - 



59 



Left knee-joint, front view. 



The prominent swelling on the left, A, is from the en- 

 laryed head of the tibia; that on the right, B, is the 

 soft globular swelling resulting from the effusion into 

 the synovial membrane. 



per and projecting margin of the inner condyle 

 of the tibia : it leans to the inner hamstring 

 muscle. The rest of the popliteal space pre- 

 sents a normal appearance. When the limb is 

 fully extended, and the muscles are allowed to 

 remain in a passive state, the patella may be 

 moved from side to side with much freedom. It 

 appears to float as it were on the surface of an 

 accumulated quantity of synovial fluid. When 

 pressed against the trochlea of the femur, this 

 fluid is moved laterally, and the patella strikes 

 against the femur, and if a lateral movement be 

 now communicated to this bone, a grating of 

 rough surfaces may be perceived. If we grasp 

 the leg and flex it on the thigh, we find we can 

 elicit a peculiar articular crepitus. In this case 

 it is quite audible, and resembles much the 

 noises which electric sparks make when dis- 

 charged in quick succession from an electrical 

 apparatus. When the limb is much flexed, 

 the swelling of course feels remarkably hard 

 and solid, but when the limb is again brought 

 back to its ordinary state of extension, fluctua- 

 tion may be felt very evidently in it over its 

 whole surface. The popliteal bursa, however, 

 is felt very tense in the extended position of 

 the joint, as when the patient stands and throws 

 his weight on the limb. If we feel this bursa, 

 and then cause the patient's limb to be flexed, 

 we can follow the fluid, as it were, with our 

 fingers into the articulation. As the patient 

 lies in bed, the limb left in the extended posi- 



Left knee-joint, side view, shewing the enlarged bursa 

 in the popliteal space, 



tion, and the synovial sac as flaccid as possible, 

 moveable bodies may be detected in its interior. 

 Some appear to be adherent, and situated more 

 particularly in the upper portion of the sub- 

 crural bursa. When we elevate the leg, and 

 preserve it still in the fully extended position, 

 the patient, without any apprehension of pain, 

 will permit us to press it firmly against the 

 femur, and does not experience the least suf- 

 fering even if we strike the heel forcibly. (See 



HlP, ABNORMAL CONDITION OF.) 



Both knee-joints in this case are affected 

 with this disease, but the left is more distended 

 by fluid than the right. The inner condyles of 

 the femur and tibia of this limb are thrown 

 somewhat inwards, and form a salient angle in 

 this direction, which, the patient says, is cer- 

 tainly the result of disease, as his limbs were 

 perfectly straight before he was visited by his 

 present illness. 



Although his knee-joints are more affected 

 with this chronic disease, his other joints pre- 

 sent very evident traces of this afflicting malady. 

 The disease in him followed a rheumatic fever, 

 which was brought on in consequence of his 

 having lain a whole night asleep on a wet road, 

 having fallen unobserved from his cart when in 

 a state of intoxication. 



Although this is not the place to speak of 

 treatment, we may be permitted to say that 

 under the influence of rest in bed and a mild 

 mercurial course, followed by a long-continued 

 use of sarsaparilla with large doses of the 

 hydriodate of potass, this man left the hospital, 

 by no means cured, but much improved and 

 tolerably well able to follow his occupation. 



