Chap. XI X.) tflP^JoiNT. 443 



incident to this there is (5) apparent shortening of 

 the limb ; (6) there is real shortening of the limb. 



1. The first position is simply the posture of 

 greatest ease. It depends mainly upon the effusion 

 into the joint. If fluid be forcibly injected into a 

 hip joint the thigh becomes flexed, abducted, and 

 a little everted. In other words, the articulation 

 holds the most fluid when the limb is in this 

 position, and the patient places it there to relieve 

 pain by reducing the tension within the capsule 

 to a minimum. Flexion is the most marked feature 

 in this position. Its effect is pronounced. It relaxes 

 the main part of the Y ligament, which, when the 

 limb is straight, is drawn as an unyielding band across 

 the front of the joint. Abduction relaxes the outer 

 limb of this ligament and the upper part of the cap- 

 sule. Eversion slightly relaxes the inner limb of the 

 Y ligament and the ischio-femoral ligament. The 

 latter movement is the least marked, since eversion, 

 even in the flexed position of the joint, is resisted by 

 the outer part of the Y ligament. Any but a moderate 

 degree of abduction would be limited by the pectineo- 

 femoral ligament, especially as that band is rendered 

 most tense when abduction is combined with flexion 

 and rotation outwards. 



2. The apparent lengthening is due to the tilting 

 down of the pelvis on the diseased side, and is the 

 result of the patient's attempts to overcome the effects 

 of the position just described. The limb is shortened 

 by flexion and abduction, and to bring the foot again 

 to the ground and to restore the natural parallelism of 

 the limbs, the pelvis has to be tilted down on the affected 

 side. Thus, an apparent lengthening is produced, 

 which is seen when the patient lies upon a bed and the 

 abduction is made to disappear. Real lengthening of 

 the limb can scarcely be produced by the effusion into 

 the joint. By forcible injection into the joint Braune 



