The effect of early fusion of the spheno-occipital synchondrosis on midface hypoplasia and obstructive sleep apnea in patients with Crouzon syndrome

Facial Malformation in Crouzon’s Syndrome Is Consistent with Cranial Base Development in Time and Space

“…This is consistent with the severe midface retrusion of Crouzon’s syndrome previously reported. 12 Conjointly analyzing this with the shorten anteroposterior length of midface (shown in our linear measurements), and unchanged midface volume in Crouzon’s syndrome, 2 reflect this hallmark facial deformity this occurs is without midface height reduction.…”

Timing of Spheno-Occipital Synchondrosis Ossification in Children and Adolescents with Cleft Lip and Palate

“…The endochondral growth centers in the midline of the cranial base have a close structural interrelationship with the nasomaxillary regions during development, influencing the future position of the maxilla [3,5,9,12]. Hence, when this relationship follows a "normal" development, a good growth of the midface is expected [3].…”

“…Previous studies reported that the fusion of the SOS occurred 2 or 3 years earlier in females than in males [7,9,[10][11][12]. The timing of complete ossification of the synchondrosis, however, is still controversial in the literature that is probably due to differences in population, criteria and diagnostic methods [24].…”

“…The SOS is a cartilaginous union between the body of the sphenoid and the basilar part of the occipital bone and it is the last of the synchondroses of the cranial base to fuse [10][11]. Its' growth will influence the anteroposterior dimension of the cranial vault (contributing to 25% of the growth of the skull base) as well as the height and depth of the upper face by moving the anterior cranial base upward and forward, and its attached maxillary complex, away from the foramen magnum [7,9,10,[12][13][14].…”

“…The literature suggests that the average fusion of the SOS normally starts around the age of 7, with a complete ossification for females between 11 to 14 years and 13 to 16 years for males, which may be related to female early growth [9,13,[15][16][17]. Premature fusion of the SOS has been associated with midface hypoplasia in humans with syndromic craniosynostoses, such as Apert and Crouzon syndromes [11][12]15,[18][19].…”