My first cousin, from Jerez Zacatecas sent me this explanation of a 
ventosa so I thought I'd share it.  It's a real combination of 
spiritual with physical which is old world... any comment from the 
Dr. in our group?

 A ventosa is as follows:  Mother would get a meduim size water 
glass and pour a little alcohol  into it and swirl it in the glass; 
then she would light it with a match and immediately place it on the 
area where the sprain was. The heat  would cause the muscle to pull 
upward into the glass and that would release the tension on it. The 
glass would remain there a few seconds and then she would repeat the 
procedure. My husband used to enjoy getting them whenever he had a 
back problem. She used them mostly on the torso. The extremeties she 
would massage with her hands after she applied an ointment. The one 
thing she did not believe in was "el mal de ojo". She called that 
brujerias (witchcraft). This is where they would apply a raw egg on 
the body and this would do  away with " el enhechizo" ( the curse) 
but, at the same time they had a lit candle and they would go back 
and forth over the body while they'd pray. It was quite interesting. 
I can't remember what else they'd use along with the egg. I tell you 
how I regret not writing all these costumbres down. 

Linda in Wa..