Multivariate correlation analysis of T1S and C7S / 中国骨伤

OBJECTIVE@#To determine whether C7 angles (C7 slope, C7S) could replace T1 angles (T1 slope, T1S) by correlation analysis of T1S and C7S.@*METHODS@#A total of 442 patients from July 2015 to July 2020 in outpatient and inpatient department were enrolled retrospectively, and 259 patients who could identify the upper endplate of T1 were screened out . Of them, there were 145 males and 114 females, aged from 20 to 83 years old with an average of (58.6±11.2) years, including 163 patients with cervical spine surgery and 96 non-surgical patients. Patients were stratified by sex, age, cervical kyphosis, cervical alignment imbalance, and cervical spine surgery. These 259 patients included 145 cases in the male group, 114 cases in the female group;76 cases in the youth group (<40 years old), 109 cases in the middle-aged group (40 to 60 years old), and 74 cases in the elderly group(>60 years old); 92 cases in the cervical kyphosis group, 167 cases in the non-kyphosis group;51 cases in the cervical sequence imbalance group, 208 cases in the non-imbalance group;163 cases in the cervical surgery group, 96 cases in the non-operation group. The correlations of C7S and T1S in various modalities groups were analyzed.@*RESULTS@#Of 442 patients, the recognition rate of upper endplate of T1 was 58.6%(259/442), and that of C7 was 90.7%. The mean T1S and C7S of the 259 patients were (24.5±8.0)° [(25.9±7.7)° in the male group and (23.7±6.9)° in the female group] and (20.8±7.3)° [(22.5±7.5)° in the male group and(19.7±5.8)° in the female group], respectively. The total correlation coefficient between C7S and T1S was r=0.89, R2=0.79, and the linear regression equation was T1S=0.91×C7S+4.35. In the above general information and the grouping of deformity factors, T1S was highly correlated with C7S(r value 0.85 to 0.92, P<0.05).@*CONCLUSION@#There is a high correlation between T1S and C7S in different factor groups. For cases where T1S cannot be measured, C7S can be used to provide guidance and reference for evaluating the sagittal balance of the spine, analyzing the condition, and formulating surgical plans.

The Effect of Cervical Lordosis on Cervical Disc Degeneration in Patients with a High T1 Slope

STUDY DESIGN: Retrospective evaluation. OBJECTIVES: To analyze the effect of cervical lordosis on cervical disc degeneration in patients with a high T1 slope. SUMMARY OF LITERATURE REVIEW: The T1 slope is known to be a parameter that may be very useful in evaluating sagittal balance. We previously reported that a low T1 slope was a potential risk factor for cervical spondylosis, especially in the C6–7 cervical segment. However, no study has analyzed the effect of cervical lordosis in patients with a high T1 slope (>25) on cervical disc degeneration. MATERIALS AND METHODS: Seventy-seven patients with a high T1 slope who underwent cervical spine MRI in our orthopedic clinic were enrolled. Patients were divided into 2 groups according to cervical compensation. The radiologic parameters obtained from radiography and cervical spine MRI were compared between the uncompensated group (cervical lordosis <25) and the compensated group (cervical lordosis ≥25). RESULTS: In the uncompensated group, the average degeneration grade of each segment was 2.72 (±0.70) in C2–3, 3.00 (±0.76) in C3–4, 3.02 (±0.91) in C4–5, 3.37 (±0.95) in C5–6, and 2.95 (±0.98) in C6–7. The average degeneration grade of each segment in the compensated group was 2.38 (±0.78) in C2–3, 2.38 (±0.60) in C3–4, 2.62 (±0.60) in C4–5, 2.82 (±0.72) in C5–6, and 2.41 (±0.74) in C6–7. The degeneration grade was significantly higher in the uncompensated group than in the compensated group for all cervical segments. The risk of high-grade degeneration of C3–4 was significantly higher in the uncompensated group (odds ratio = 6.268; 95% CI, 2.232–17.601; p<.001). CONCLUSIONS: Patients with a high T1 slope without compensation of cervical lordosis had a higher grade of degeneration in all cervical segments.

The Use of T1 Sagittal Angle in Predicting Cervical Disc Degeneration

STUDY DESIGN: Retrospective evaluation. PURPOSE: To analyze the effect of T1 slope on degree of degeneration in patients with cervical disc degeneration. OVERVIEW OF LITERATURE: The T1 slope is well known parameter that may be very useful in evaluating sagittal balance. There are no reports on the analysis of the relationship between T1 slope and cervical disc degeneration. We hypothesized that T1 slope has an effect on the degree of cervical degeneration. METHODS: Sixty patients who had cervical spine magnetic resonance imaging (MRI) in our orthopedic clinic were enrolled. Patients were divided into two groups according to T1 slope. Radiologic parameters obtained from radiography and cervical spine MRI were compared between low T1 slope group (25). RESULTS: Among low T1 slope group, average degeneration grade of each cervical segment was 2.65 in C2-3, 2.50 in C3-4, 2.62 in C4-5, 3.23 in C5-6, and 2.81 in C6-7. And that of high T1 group was 2.35 in C2-3, 2.32 in C3-4, 2.59 in C4-5, 2.79 in C5-6, and 2.32 in C6-7. Grade of degeneration of low T1 group was significantly higher, as compared with high T1 group in C5-6 (p=0.028) and C6-7 (p=0.009). Percentage of high grade degeneration of more than grand III was 65.4% in low T1 group and 32.4% in high T1 group (p=0.018). Risk of high grade degeneration of C6-7 was significantly higher in low T1 group (odds ratio, 5.63; 95% confidence interval, 1.665-19.057; p=0.005). CONCLUSIONS: Patients with low T1 slope had higher grade of degeneration regardless of age and gender. Low T1 slope is a potential risk factor of cervical spondylosis especially in the C6-7 cervical segment.

T1 Slope and Cervical Sagittal Alignment on Cervical CT Radiographs of Asymptomatic Persons

OBJECTIVE: We performed a retrospective analysis of medical records and radiographic images of patients who never underwent spinal treatment including diagnosis. The objective of this study is to explain the biomechanical and physiologic characteristics of cervical alignment related to thoracic inlet angle including T1 slope changes in each individual. METHODS: We reviewed the cervical CT radiographs of 80 patients who visited ENT outpatient clinic without any symptom, diagnosis and treatment of cervical spine from January 2011 to September 2012. All targeted people were randomized without any prejudice. We assessed the data-T1 slope, Cobb's angle C2-7, neck tilt, sagittal vertical axis (SVA) C2-7 and thoracic inlet angle by the CT radiographs. RESULTS: The relationships between each value were analyzed and we concluded that Cobb's angle C2-7 gets higher as the T1 slope gets higher, while the SVA C2-7 value decreases. CONCLUSION: We propose that the T1 slope is background information in deciding how much angle can be made in the cervical spinal angle of surgical lordotic curvature, especially severe cervical deformity.