Traditionally, the Carthusians genuflected by bending the knee, yet so as not to let it touch the ground at the consecration of the Holy Eucharist. At other times, Carthusians make a profound bow.
Given that the Church has experienced so many liturgical changes in the past 50 years, does any know if the Carthusians still do this?
Incidentally, everyone else not allowed to do it Carthusian style. A Decree of the S. Cong. of Rites (n. 3402) states that all the faithful ought to perform a full genuflection if physically possible.