Wildervanck syndrome is characterized by the triad of cervical vertebral fusion (Klippel-Feil anomaly, see this term), bilateral abducens palsy with retracted eyes (Duane syndrome, see this term) and congenital perceptive deafness.

HDR syndrome (HDRS), also known as Barakat syndrome, is a heterogeneous disorder characterized by the triad of Hypoparathyroidism (H), nerve Deafness (D) and/or Renal disease (R). Variable clinical features include hypogonadotrophic hypogonadism, polycystic ovaries, congenital heart disease, retinitis pigmentosa, and cognitive disability (Barakat et al., 2018).