High Prevalence of Cervical Deformity and Instability Requires Surveillance in Loeys-Dietz Syndrome

Background: Loeys-Dietz syndrome is a connective tissue disorder characterized by vascular, craniofacial, and musculoskeletal malformation. Our goal was to report the manifestations, surgical treatment, and complications in the cervical spine in patients with Loeys-Dietz syndrome. Methods: We reviewed the clinical and cervical spine imaging data of eighty patients with Loeys-Dietz syndrome who were seen at our institution from January 2005 through January 2014. Their mean age at presentation was 17.3 years (range, three months to seventy-five years). We tested associations with use of the Fisher exact test (type of TGF-beta R [transforming growth factor-beta receptor] mutation and cervical abnormalities) and the Student t test (age at presentation and type of TGF-beta R mutation) (significance, p = 0.05). Results: Vertebral anomalies and cervical instability were common; we found no significant association of TGF-beta R-type with cervical abnormalities or age at presentation. Twenty-eight patients had atlas defects (anterior and/or posterior arch defects or hypoplasia), fifty-three had axis malformations (elongation, apex-anterior dens angulation, or spondylolysis), and twelve had focal kyphosis. Ten patients had hypoplastic subaxial vertebrae, leading to focal kyphosis (eight) and subaxial instability (nine). Eight patients had atlantoaxial instability. Of the thirteen patients with cervical instability, nine were treated surgically: fusion (eight patients) and halo application (one) (mean age, four years; range, three months to twelve years). Postoperative complications (seven patients) were pseudarthrosis, failure of fixation, junctional kyphosis or instability, and development of occipital-cervical instability. Conclusions: Cervical midline defects (most often C1-C3) are common in Loeys-Dietz syndrome. Patients have a high prevalence of cervical instability, particularly a pattern of instability at C2-C3 associated with C3 vertebral body hypoplasia and C2-C3 focal kyphosis. Patients requiring surgery typically present in early childhood.