Table 1.
Demographics of patients and radiological findings among the five groups divided by the DHG
| Characteristic | DHG 0 | DHG 1 | DHG 2 | DHG 3 | DHG 4 | p-value |
|---|---|---|---|---|---|---|
| Anterior slippage | ||||||
| No. of disc level | 6 | 25 | 11 | 6 | 4 | |
| Age (yr) | 71.7±4.1 | 71.6±9.8 | 76.9±7.4 | 71.2±9.2 | 68.5±10.9 | 0.509 |
| Sex | ||||||
| Male | 2 | 20 | 7 | 2 | 2 | 0.093 |
| Female | 4 | 5 | 4 | 4 | 2 | |
| Disesase | 0.426 | |||||
| CSM | 4 | 24 | 9 | 5 | 3 | |
| OPLL | 2 | 1 | 1 | 0 | 1 | |
| Others | 0 | 0 | 1 | 1 | 0 | |
| Slipped levela) | 4.2±1.6 | 5.0±1.9 | 4.2±1.5 | 4.2±1.2 | 4.5±1.7 | 0.597 |
| Slippage in Flex (mm) | 2.3±0.3 | 3.3±0.6 | 3.6±0.7 | 3.1±0.9 | 2.9±0.9 | 0.023 |
| Slippage in neutral (mm) | 2.2±0.4 | 2.8±0.6 | 2.7±0.5 | 2.9±1.0 | 2.4±0.6 | 0.515 |
| Slippage in Ext (mm) | 1.0±0.8 | 1.8±1.0 | 0.7±0.8 | 1.5±1.4 | 0.2±0.3 | 0.046 |
| Translation of slippage (mm) | 1.2±0.8 | 1.4±0.7 | 2.8±1.1 | 1.6±1.5 | 2.8±0.7 | 0.007 |
| Type of facet joint | 0.170 | |||||
| Posteromedial | 4 | 8 | 6 | 4 | 1 | |
| Transitional | 1 | 7 | 3 | 1 | 0 | |
| Posterolateral | 1 | 10 | 2 | 1 | 3 | |
| Saggital facet slope (°) | 31.3±6.8 | 19.8±11.1 | 21.8±10.2 | 20.5±10.3 | 25.3±22.1 | 0.275 |
| Alignment type | 0.697 | |||||
| A: lordosis | 1 | 7 | 3 | 1 | 1 | |
| B: straight | 1 | 8 | 3 | 2 | 1 | |
| C: kyphosis | 0 | 3 | 2 | 0 | 0 | |
| D: sigmoid cranial lordosis | 2 | 3 | 0 | 1 | 1 | |
| E: sigmoid cranial kyphosis | 2 | 4 | 3 | 2 | 1 | |
| C2–C7 angle (°) | 7.0±8.5 | 5.6±15.7 | 6.9±10.4 | 12.8±11.0 | 9.5±8.1 | 0.123 |
| C2–C7 SVA (mm) | 20.7±10.5 | 36.1±17.9 | 27.5±13.7 | 29.2±15.3 | 17.5±25.4 | 0.123 |
| Flex C2–C7 angle (°) | −14.8±9.9 | −13.9±16.6 | −13.4±10.4 | −2.2±11.4 | −12.0±6.7 | 0.439 |
| Ext C2–C7 angle (°) | 24.7±9.0 | 19.5±12.2 | 17.6±12.0 | 30.8±8.7 | 18.0±12.1 | 0.175 |
| ROM (°) | 39.5±10.5 | 33.4±14.2 | 30.9±12.0 | 33.0±11.7 | 30.0±11.9 | 0.736 |
| Slipped disc angle (°) | 0.7±5.4 | 0.3±5.8 | 0.1±2.9 | −0.5±4.4 | −0.3±2.5 | 0.994 |
| Slipped disc ROM (°) | 8.3±7.5 | 7.8±5.3 | 9.1±3.8 | 8.0±7.0 | 8.0±2.6 | 0.983 |
| Posterior slippage | ||||||
| No. of disc level | 0 | 0 | 0 | 8 | 23 | |
| Age (yr) | 66.0±11.4 | 66.4±9.2 | 0.915 | |||
| Sex | 0.445 | |||||
| Male | 7 | 17 | ||||
| Female | 1 | 6 | ||||
| Disesase | 0.173 | |||||
| CSM | 8 | 18 | ||||
| OPLL | 0 | 1 | ||||
| Others | 0 | 4 | ||||
| Slipped levela) | 4.4±1.2 | 4.3±1.0 | 0.872 | |||
| Slippage in Flex (mm) | −1.6±1.0 | −2.8±1.2 | 0.022 | |||
| Slippage in neutral (mm) | −2.7±0.7 | −3.5±1.2 | 0.068 | |||
| Slippage in Ext (mm) | −2.7±0.7 | −3.7±1.2 | 0.050 | |||
| Translation of slippage (mm) | 1.1±1.6 | 0.9±0.9 | 0.638 | |||
| Type of facet joint | 0.826 | |||||
| Posteromedial | 1 | 9 | ||||
| Transitional | 4 | 0 | ||||
| Posterolateral | 3 | 14 | ||||
| Saggital facet slope (°) | 26.9±9.3 | 30.0±11.5 | 0.499 | |||
| Alignment type | 0.661 | |||||
| A: lordosis | 5 | 7 | ||||
| B: straight | 0 | 6 | ||||
| C: kyphosis | 0 | 1 | ||||
| D: sigmoid cranial lordosis | 0 | 2 | ||||
| E: sigmoid cranial kyphosis | 3 | 7 | ||||
| C2–C7 angle (°) | 15.9±21.2 | 8.8±14.4 | 0.298 | |||
| C2–C7 SVA (mm) | 25.0±15.5 | 21.8±17.0 | 0.646 | |||
| Flex C2–C7 angle (°) | −13.1±20.1 | −10.9±14.9 | 0.745 | |||
| Ext C2–C7 angle (°) | 27.4±21.9 | 24.7±12.7 | 0.683 | |||
| ROM (°) | 40.5±11.0 | 35.6±12.2 | 0.331 | |||
| Slipped disc angle (°) | 6.5±4.0 | 1.7±8.1 | 0.123 | |||
| Slipped disc ROM (°) | 9.0±4.1 | 7.7±4.5 | 0.474 | |||
Values are presented as number or mean±standard deviation. The bold type is considered statistically significant.
DHG, disc height grade; CSM, cervical spondylotic myelopathy; OPLL, ossification of posterior longitudinal ligament; Flex, flexion; Ext, extension; SVA, sagittal vertical axis; ROM, range of motion.
a)
If it was a C4 spondylolisthesis, it was evaluated as 4.