Cephalometric findings in facioscapulohumeral muscular dystrophy patients with obstructive sleep apneas

The purposes of the study are: (1) to establish if cephalometry and upper airway examination may provide tools for detecting facioscapulohumeral (FSHD) patients at risk for obstructive sleep apnea syndrome (OSAS); and (2) to correlate cephalometry and otorhinolaryngologic evaluation with clinical and polysomnographic features of FHSD patients with OSAS.

Patients were 13 adults affected by genetically confirmed FSHD and OSAS, 11 men, with mean age 47.1 ± 12.8 years (range, 33-72 years). All underwent clinical evaluation, Manual Muscle Test, Clinical Severity Scale for FSHD, Epworth Sleepiness Scale, polysomnography, otorhinolaryngologic evaluation, and cephalometry.

Cephalometric evidence of pharyngeal narrowing [posterior airways space (PAS) < 10 mm] was present in only one patient. The mandibular planus and hyoid (MP-H) distance ranged from 6.5 to 33.1 mm (mean, 17.5 ± 7.8 mm). The mean length of soft palate (PNS-P) was 31.9 ± 4.8 mm (range, 22.2 to 39.7 mm). No patient presented an ANB angle > 7°. There was no significant correlation between cephalometric measures, clinical scores, and PSG indexes. PAS and MP-H were not related to the severity of the disease.

Upper airway morphological evaluation is of poor utility in the clinical assessment of FSHD patients and do not allow to predict the occurrence of sleep-related upper airway obstruction. This suggests that the pathogenesis of OSAS in FSHD is dependent on the muscular impairment, rather than to the anatomy of upper airways.