Ihe Region of the Knee Joint. 357 



the patellar ligament, and, further, that fluctuation, from 

 one side of these structures to the other is readily elicit- 

 ed. In synovitis, the patella is raised up from the 

 trochlear surface, on which it normally lies, so that, on 

 pressure backwards over it, it feels as though it rested on 

 a "water-bed." When, in synovitis, a constriction appears 

 about one inch above the patella with a swelling immed- 

 iately above it, it means that there is a communication pre- 

 sent between the sub-quadriceps bursa and the knee joint. 



Tuberculosis of the knee joint, in the young, ap- 

 pears first, as a rule, in the bones of the articulation and 

 in the following order, viz. : Femur, tibia and patella ; 

 wheraes, in the older patient, the disease very often begins 

 in the synovial membrane of the joint. When the bone is 

 affected, movement, in the early stages at least, causes 

 very little pain, but when the synovial membrane is dis- 

 eased, pain on movement is excessive. When the disease 

 begins in the synovial membrane there is a point of maxi- 

 mum tenderness, acording to Harwell, in front of the in- 

 ternal condyle, about half an inch internal to the patella. 

 In the young, the disease may start beneath the encrusting 

 cartilage, or in the neighborhood of the epiphyseal line, 

 causing early enlargement o-f the epiphysis and tenderness 

 along the epiphyseal line. Abscess was present, accord- 

 ing to Gibney, in one hundred and forty out of three hun- 

 dred cases of tuberculosis of the knee joint, and it must 

 not be forgotten that such abscesses may burrow towards 

 and open upon the skin, without involving the in- 

 terior of the joint at all, so that, the less severe operation of 

 curetting the diseased bone may save an incision of the 

 joint. In inflammatory affections of the knee j oint flexion is 

 generally present. This flexion, in synovitis with effusion, 

 may depend on the fact that, when the leg is semi-flexed, 

 the cavity of the joint contains a greater amount of fluid, 



