Arthritis Deformans of Sacro-iliac Joint. 489 



7. 164. Arthritis Deformans, involving- the Patella.— 



Patella of an elderly person — macerated, illustrating the above. 

 There is a slight enlargement at the articular margin, and a 

 development of bone in the position of the ligamentum patella?. 



B. C. II. M. 60. 



7. 165. Arthritis Deformans, involving- the Patella.— Two 



patella, apparently from the same subject — macerated, showing 

 characteristic changes. 



The articular surface has been bared of cartilage and marked 

 by deep grooves, with an eburnated surface. There is also some 

 enlarerement at the margin of each bone. B. C. ii. M. 25. 



SACKO-ILIAC JOINT. 



7. 166. Arthritis Deformans, involving- the Joints of the 



Pelvis. — Pelvis of an elderly person — macerated, illustrating 

 the above. 



The bony ridges are well marked, but the bone itself is 

 somewhat light. There is anchylosis of both sacro-iliac joints at 

 their upper margins. There is also enlargement round the 

 upper border of the body of the first sacral vertebra. The 

 margins of the acetabula are irregular from slight bony over- 

 growth, but the cavities themselves are somewhat shallower and 

 wider than usual, as if they had yielded to pressure. 



G. C. 997. 



HIP-JOINT. 

 167. Early Stag-e of Arthritis Deformans.— Bones forming 



a left hip-joint — in spirit, illustrating the above. 



The cartilage on the femur is at the upper part somewhat 

 shreddy and irregular, and at one spot it has been worn away^ 

 showing an eburnation of the bone below. The enlargement at 



