To date, six underlying types of disease have been identified and are categorised as follows: classical (formerly type I/II), hypermobility (formerly type III), vascular (formerly type IV), kyphoscoliosis (formerly type VI), arthrochalasia (formerly type VIIA/VIIB), and dermatosparaxis
(formerly type VIIC) .
The various types include--classic; hypermobility; vascular; kyphoscoliosis; arthrochalasia; and dermatosparaxis
. The vascular type (EDS IV) is rare (<4%) and is caused by mutation of the type III procollagen (COL3A1) gene that results in fragile medium and large arteries.
With recent developments and increased medical expertise, a simplified classifica-tion of EDS has been revised into six major types namely Classical, Hypermobility, Vascular, Ky-phoscoliosis, Arthroclasia, and Dermatosparaxis
.6 Kyphoscoliosis type of EDS (Type VI in previous clas-sification) is attributed to a deficiency in lysyl hy-droxylase (LH), the enzyme that hydroxylates spe-cific lysine residues in the collagen molecule to form hydroxylysines with 2 important functions.
The six major types of EDS are (a) classical type, (b) hypermobility type, (c) vascular type, (d) kyphoscoliosis type, (e) arthrochalasia type, and (f) dermatosparaxis
type (Beighton et al., 1998).