346 HENRY JACOB BIGELOW. 



or both of its branches, the Y ligament dominated all the dislocations 

 of the hip joint with established features, and that it was the chief 

 obstacle to reduction ; the muscles playing only a subordinate and 

 occasional part in giving position to the limb, or in hindering the 

 reduction. 



" Dr. Bigelow classified dislocations of the hip into regular and 

 irregular. 



"The regular dislocations, seven in number (four of them being 

 new varieties), are those in which, one or both branches of the Y liga- 

 ment being unbroken, the head of the femur is thereby held near the 

 acetabulum, and their signs are constant. 



" The irregular dislocations are those in which the Y ligament is 

 wholly ruptured, and they therefore offer no constant signs. The 

 head of the femur, being loosed from the acetabulum, is free to go 

 anywhere. 



" In the regular dislocations, manipulation of the Y ligament will 

 alone effect reduction. 



*' The principle of this manipulation is flexion, which is efficient 

 because it relaxes the Y ligament. 



" The Y ligament being flexed, and therefore relaxed, the head of 

 the femur is drawn or forced into the desired direction by ' traction,' 

 which disengages it from behind the acetabulum and directs it toward 

 the socket, — or by ' rotation,' which winds the Y ligament around 

 the neck of the bone and so shortens it, thus compelling the head of 

 the femur, as it sweeps around the acetabulum, also to approach the 

 socket, into which it can be easily lifted. 



" Dr. Bigelow converted random, ill devised, and fruitless move- 

 ments into accurately conceived, instructed, and well directed manip- 

 ulation," 



Growing out of his investigations of this subject was his original 

 study of the anatomical neck of the femur. By a series of parallel 

 sections through the head and neck of the bone, he demonstrated the 

 column or lamina of condensed bone in the midst of the cancellated 

 tissue forming a line of support rendered necessary by the obliquity 

 of the neck of the bone. 



In 1878 Dr. Bigelow published his essay, " Lithotrity by a Single 

 Operation," of which Dr. Hodges speaks as follows : — 



^^Rapid Lithotrily with Evacuatio7i at a slnrjh sitting ; or Lithola- 

 faxy. — The normal urethra having been shown to admit instruments 

 of greater size than surgeons had previously supposed possible, Dr. 

 Bigelow constructed a lithotrite, improved in many of its details, 



