Yes, there is a discussion in the book 'The Serpent Power' by Sir John Woodroffe (Arthur Avalon).
It is to be noted that, just as there are five centres (Cakras)
hereinafter described, the vertebral column itself is divided into
five regions, which commencing from the lowest, are the coccygeal,
consisting of four imperfect vertebrae, often united together into one
bone called the coccyx; the sacral region, consisting of five
vertebrae united together to form a single bone, the sacrum; the
lumbar region, or region of the loins, consisting of five vertebrae;
the dorsal region, or region of the back, consisting of twelve
vertebrae; and the cervical region, or the region of the neck,
consisting of seven vertebrae. As exhibited by segments, the cord
shows different characteristics in different regions. Roughly
speaking, these correspond to the regions assigned to the governing
control of the Muladhara, Svadhisthana, Manipura, Anahata and Visuddha
centres or Cakras or Lotuses (Padma).
The Serpent Power by Arthur Avalon (Sir John Woodroffe) Chapter V, The Centres or Lotuses (Cakra, Padma)