A Radiographic Analysis of Cervical Sagittal Alignment in Adolescent Idiopathic Cervical Kyphosis
The aim of this study was to analyze the radiologic features of adolescent idiopathic cervical kyphosis.Summary of Background Data:
There are few previous reports about radiographic analysis of cervical sagittal alignment of adolescent idiopathic cervical kyphosis. A new method was proposed in this article to evaluate the severity of cervical kyphosis.Patients and Methods:
A total of 41 adolescent patients with cervical kyphosis were reviewed. Several angles were measured from the radiographs utilizing the 2-line Cobb method and Harrison posterior tangent method. Ishihara’s Curvature Index (CI), Kyphosis Index (KI), kyphosis levels, and the apex of the kyphosis were also measured.Results:
The results showed that the apex of the kyphosis is located at the posterior-superior edge of C4 (70.7%) and C5 (29.3%). C2–C7 angles ranged from 4.7 to 71.3 degrees (36.2±13.6 degrees) and from 9.8 to 83.1 degrees (36.4±15.1 degrees) in the above 2 methods, respectively. Local angles of kyphotic area ranged from 21.8 to 96.3 degrees (50.5±23.7 degrees) in 2-line Cobb method and from 19.8 to 105.6 degrees (52.0±19.5 degrees) in Harrison posterior tangent method. CI and KI ranged from 8.6 to 79.8 (36.8±16.7) and 15.2 to 141.9 (50.6±23.7), respectively. Statistical analysis showed that there was significant positive correlation between KI and kyphosis angle.Conclusions:
In adolescent idiopathic cervical kyphosis, the alteration of the sagittal profile only occurs on partial cervical alignment rather than the whole cervical spine. The apex of the kyphosis locates at posterior-superior edge of the vertebrae. It seems that KI can accurately depict the severity of cervical kyphosis.