Arthritis Deformans of Hip-joint. 491 



left hip-joint of an elderly person — the femur sawn verticallj' — 

 macerated, illustrating the above. 



The head of the femur is enlarged, chiefly by a new 

 bone formation at the margins, which extends to the neck. 

 The upper part of the head is smooth and shining, and, except 

 that it is porous in places, might pass for a portion of a billiard 

 ball. The surface of the new bone on the front of the neck and 

 upper part of the shaft is porous and irregular. The interior of 

 the bone shows condensation at the centre of the head, with 

 some empty spaces near the articular margin. The cavity of 

 the acetabulum is somewhat shallow, and the bottom is entirely 

 filled up with new bone. The articular surface is somewhat 

 porous above, but shows a band of eburnation all round. The 

 cotyloid margin is irregularly prolonged, and some rough new 

 bone has been formed all round and beyond it. The capsular 

 ligament is said to have had bony excrescences attached to it. 



G. C.1481. 

 Presented by Professor J. W. Turner and A. Watson, F.E.C.S.E. 



7. 171. Advanced Arthritis Deformans, with Locking*. — 



Bones forming the right hip-joint of an elderly person, in which 

 the head of the femur is locked within the acetabulum — 

 macerated. 



There is some irregular enlargement at the articular 

 margin of the head of the femur. The lesser trochanter has 

 been entirely worn away against a piece of the bone, which pro- 

 jects from just below the acetabulum, and the adjacent surfaces 

 are adapted to one another. The hip-joint has been fixed in a 

 strongly adducted position. The margin of the acetabulum is 

 deepened, and has grown inwards so as to envelop the head of 

 the femur, A slight range of movement is possible between 

 the femur and the acetabulum, but it is doubtful whether this 

 existed before maceration. There is a small semi-detached 

 scale of bone, with a depression near it in the cavity of the 

 ilium, the nature of which is obscure. 



