The impact of age, sex, disc height loss and T1 slope on the upper and lower cervical lordosis: a large-scale radiologic study

Abstract

Purpose To clarify the relative influence of age, sex, disc height loss and T1 slope on upper (Occiput-C2) and lower cervical lordosis (C2–C7). Methods Standing lateral cervical radiographs of 865 adult subjects were evaluated. The presence and severity of disc height loss from C2/C3 to C6/C7 (a total of 4325 discs) were assessed using a validated grading system. The total disc height loss score for each subject was calculated as the sum of the score of each disc space. Sagittal radiographic parameters included: occipital slope, occiput-C2 (Oc-C2) lordosis, C2–C7 lordosis and T1 slope. Multivariable regression analyses were performed to examine the relative influence of the multiple factors on upper and lower cervical lordosis. Results This study included 360 males and 505 females, with a mean age of 40.2 ± 16.0 years (range, 20–95 years). Linear multivariate regression analyses showed that greater age, male sex, greater T1 slope were each found to be significantly and independently associated with greater C2–C7 lordosis, whereas total disc height loss score was negatively associated with C2–C7 lordosis. T1 slope had the most independent influence on C2–C7 lordosis among these factors. Age, sex and disc height loss were not independently associated with Oc-C2 lordosis. Conclusions Results from our large-scale radiologic analysis may enhance the understanding of the factors that affect cervical lordosis, indicating that age, sex, disc height loss and T1 slope were each independently associated with C2–C7 lordosis. However, age, sex and disc height loss were not independently associated with upper cervical lordosis.

The Relationship Between Increased Intervertebral Disc Height (IDH) and Development of Postoperative Dysphagia After Single-level Anterior Cervical Discectomy and Fusion (ACDF) — A retrospective Study of 217 Cases

“…To date, very few radiological studies directly investigated the independent in uence of IDH and SP on postoperative dysphagia. It has been previously reported that IDH loss causes ventral angulation and eventual loss of cervical lordosis 13 during cervical and Tao et al 10 found that total disc height loss score was negatively associated with C2-C7 lordosis in a large-scale radiologic study of 865. On the contrary, C2-C7 lordosis was also restored when central interbody fusion was conducted to enlarge IDH during ACDF.…”

“…Fifth, the effect of ethnicity on the sagittal alignments of the cervical spine was not taken into consideration so that our results may be not globally generalizable 23 . Last but not least, our study did not include lateral radiographs of the full spine, and the relationship between postoperative dysphagia and other global sagittal parameters, such as thoracolumbar alignments, could thus not to be discussed 10 .…”

“…However, few studies have correlated the postoperative dysphagia after ACDF with change of middlelower cervical height, such as IDH and SP. Recently, a large-scale retrospective radiologic analysis showed that height loss was independently associated with middle-lower cervical lordosis 10 . What's more, it's reported that the mean increase in IDH after ACDF was 2.62 mm 11 and Olsewski et al 12 found that distracting the disc space 3.0 mm beyond its original height led to a signi cant biomechanical changes.…”

Endplate abnormalities, Modic changes and their relationship to alignment parameters and surgical outcomes in the cervical spine

“…Several studies have demonstrated that ACDF can change alignment parameters, 18,19 of which have been associated with patient reported outcomes 20 . Furthermore, T1‐slope has also been implicated in affecting CL of the lower cervical spine as opposed to the upper region, but the role of the aforementioned endplate‐related phenotypes in this constellation remains unknown 21 …”

“…20 Furthermore, T1-slope has also been implicated in affecting CL of the lower cervical spine as opposed to the upper region, but the role of the aforementioned endplate-related phenotypes in this constellation remains unknown. 21 In addition to the paucity of data linking MC and endplate abnormalities to cervical spine pain, it remains relatively speculative as to the role of these two imaging phenotypes with respect to deviations of normal CL and T1 slope. As such, the purpose of this study was to evaluate the impact of MC and endplate abnormalities on preoperative, postoperative, and changes in cervical alignment following ACDF.…”