POLL-EVIL 109 



neath which hes the spinal cord unprotected 

 by bony covering. Above the intervertebral 

 ligament there is a thick musculature and the 

 funicular portion of the ligamentum nuchse. 



The occipito-atlantoid articulation is a diar- 

 throsis whose large capsular ligament is ar- 

 ranged to include both occipital condyles. It 

 is protected superiorly by muscles which also 

 separate it from the ligament laterally. 



The atlantoid bursa — the initial seat of al- 

 most all poll-evils — lies between the ligamen- 

 tum nuchge and the dorsal arch of the atlas. 

 This bursa has no connection with the articu- 

 lation. 



The spinal cord is exposed in two places to 

 both the disease and the operation against poll- 

 evil. It is, however, in the atlanto-axoid space 

 that it is most likely to be encroached upon. 

 The musculature covering it in the atlanto- 

 axoid space or the intervertebral ligament, is 

 usually the floor of the abscess cavity but some- 

 times these structures are degenerated and per- 

 forated in a downward direction until first the 

 meninges and later the cord becomes involved. 

 The cord exposure in the space is about one 

 and a half to two inches. The cord must also 

 be thought of when packing wound cavities 

 with hemostatic packs because its covering is 

 compressible and considerable spinal pressure 



