Epiconus, Conus, Periconus and Cauda Equina

Anatomically, the epiconus comprises the cord segment between L4 and S1, corresponding to the T12 and L1 vertebrae.*

The conus medullaris consists of the cord segment between S2 and S5 as well as coccygeal segments.**

Anatomically periconus includes the Epiconus and Conus Medullaris

The cauda equina is a structure within the lower end of the spinal column that consists of nerve roots and rootlets from spinal segments L3 to Coccygeal nerve. At the base of the Cauda Equina, there are approximately 10 root pairs, 3-5 lumbar, 5 sacral, and the single coccygeal nerve.

*= Bullough P G, Boachie-Adjei O. Development of the Spinal Cord. 

 In: Atlas of the Spinal Diseases. JB Lippincott: Philadelphia, 1988,pp53.

** =  Di Pietro M A. The conusmedullaris : normal US findings throughout childhood.

Radiology 1993; 188: 149 - 153.