Abstract
Background. The state of the cervical spine in patients with Scheuermanns disease has still not been studied enough. This concerns the magnitude of cervical lordosis in the norm and in juvenile kyphosis in both pre- and postoperative periods, as well as the relationship of these changes with the spinopelvic parameters. There is almost no information on the correlation between the state of cervical lordosis and the development of proximal transitional kyphosis.
Aim of the study. To determine the features of the cervical spine in patients with Scheuermanns disease in the pre- and postoperative periods by analyzing the literature data.
Results. The literature data do not allow us to clearly define the limits of normal in the quantitative assessment of cervical lordosis. The only thing all researchers agree on is that the cervical lordosis should be considered discretely, namely at the C1-C2 and C2-C7 levels. The most commonly used parameters of the cervical-thoracic junction are T1 slope, thoracic inlet angle (TIA) and position of the sagittal vertical axis (SVA).
The magnitude of cervical lordosis in Scheuermanns disease varies from 4 to 35, i.e., thoracic kyphosis increase is not always accompanied by the development of compensatory cervical hyperlordosis. In thoracic deformities (the apex is at the level of T10 and cranial), the magnitude of cervical lordosis is significantly greater than that in thoracolumbar deformities (the apex is at the level of T11 and caudal). In the first case, the cervical lordosis (C2-C7) is 19.4-26.2, while in the second one 4.7-8.5.
Very few literature data demonstrate that in terms of cervical lordosis dynamics, patients with Scheuermanns disease do not represent a homogeneous group. The only pattern is that the cervical lordosis increases slightly in the longterm postoperative period. The spinopelvic parameters in patients with Scheuermanns disease differ little from the normal ones and almost do not change after corrective interventions. We could not find any publications attempting to relate the risk of PJK to cervical-thoracic junction parameters (T1, TIA, SVA).
Conclusion. The state of the cervical spine in patients with severe forms of Scheuermanns disease, subject to surgical correction, has not been studied enough. This concerns the magnitude of cervical lordosis, its dynamics in the postoperative period, its relationship with spinopelvic parameters, as well as the correlation between parameters of transitional cervical-thoracic spine and development of proximal transitional kyphoses. Further studies of this problem are needed.