TABLE 4.
Comparison of radiographic and clinical assessment between groups SSV and SSV− and between groups SSV and SSV+ (Ps: 0‐SSV−; 1‐SSV; 2‐SSV+).
| Group | Group | Group | p‐value (0,1) | p‐value (0,2) | p‐value (1,2) | |
|---|---|---|---|---|---|---|
| SSV− | SSV | SSV+ | ||||
| (n = 25) | (n = 27) | (n = 26) | ||||
| Age (years) | 60.8 ± 6.4 | 61.3 ± 7.0 | 63.3 ± 5.5 | 0.943 | 0.340 | 0.510 |
| Gender (M/F) | 6/19 | 8/19 | 2/24 | 0.197 | 0.140 | 0.091 |
| Body mass index (kg/m2) | 25.3 ± 3.2 | 25.1 ± 3.6 | 25.3 ± 3.8 | 0.985 | 1.000 | 0.988 |
| BMD T‐value | −1.7 ± 2.1 | −2.8 ± 1.3 | −2.9 ± 1.3 | 0.045* | 0.021* | 0.709 |
| CT HU | 122.6 ± 43.7 | 117.8 ± 47.4 | 97.0 ± 42.8 | 0.925 | 0.121 | 0.216 |
| Osteoporosis (Y/N) | 11/14 | 15/12 | 16/10 | 0.444 | ||
| Hypertension (Y/N) | 8/17 | 7/20 | 7/19 | 0.875 | ||
| Diabetes (Y/N) | 0/25 | 2/25 | 3/23 | 0.316 | ||
| Other complications | 1.0 ± 1.5 | 1.0 ± 1.6 | 1.0 ± 1.2 | 0.984 | 0.947 | 0.989 |
| Fusion levels | 3.8 ± 1.3 | 5.6 ± 1.9 | 6.4 ± 1.7 | <0.001* | <0.001* | 0.053 |
| Follow‐up (months) | 41.1 ± 16.4 | 48.0 ± 20.9 | 47.8 ± 20.0 | 0.521 | 0.451 | 0.985 |
| Osteotomy | ||||||
| PCO | 3 | 1 | 5 | 0.341 | 0.465 | 0.050 |
| Grade 3/4 | 22 | 26 | 21 | |||
| DJF (Y/N) | 3/22 | 4/23 | 6/20 | 1.000 | 0.465 | 0.676 |
| LIV | ||||||
| OV + 2 | 16 | 4 | 2 | <0.001* | ||
| OV + 3 | 7 | 18 | 11 | |||
| OV + more than 3 levels | 2 | 5 | 13 | |||
| Operation time (minutes) | 220.1 ± 51.1 | 264.9 ± 69.7 | 304.2 ± 80.5 | 0.022* | <0.001* | 0.034* |
| Estimated blood loss (mL) | 806.0 ± 506.3 | 812.9 ± 265.2 | 1388.7 ± 896.5 | 0.969 | 0.001* | 0.001* |
| GK (°) | ||||||
| Preoperatively | 62.6 ± 15.1 | 61.2 ± 16.3 | 56.2 ± 22.4 | 0.781 | 0.201 | 0.330 |
| Postoperatively | 23.5 ± 11.5 | 21.2 ± 13.4 | 15.7 ± 9.1 | 0.777 | 0.065 | 0.777 |
| At final follow‐up | 26.6 ± 13.5 | 18.4 ± 11.7 | 18.4 ± 9.7 | 0.031* | 0.032* | 0.991 |
| p‐value | <0.001* | <0.001* | <0.001* | |||
| Correction rate (%) | 63.5% ± 17.5% | 67.6% ± 17.9% | 71.7% ± 16.3% | 0.440 | 0.122 | 0.422 |
| TK (°) | ||||||
| Preoperatively | 43.0 ± 15.7 | 41.2 ± 14.7 | 28.2 ± 18.3 | 0.700 | 0.002* | 0.007* |
| Postoperatively | 31.1 ± 29.9 | 30.6 ± 11.3 | 23.2 ± 11.3 | 0.929 | 0.173 | 0.173 |
| At final follow‐up | 31.9 ± 13.4 | 28.6 ± 9.9 | 28.7 ± 13.8 | 0.397 | 0.417 | 0.980 |
| p‐value | 0.013* | 0.001* | 0.459 | |||
| TLK (°) | ||||||
| Preoperatively | 46.7 ± 13.5 | 44.9 ± 15.5 | 39.9 ± 18.2 | 0.679 | 0.134 | 0.281 |
| Postoperatively | 15.1 ± 9.1 | 12.7 ± 12.6 | 9.4 ± 8.6 | 0.457 | 0.078 | 0.260 |
| At final follow‐up | 17.4 ± 12.1 | 12.0 ± 8.0 | 11.8 ± 7.4 | 0.068 | 0.062 | 0.950 |
| Change in TLK | 29.2 ± 16.6 | 32.5 ± 16.2 | 29.6 ± 19.9 | 0.528 | 0.943 | 0.567 |
| p‐value | <0.001* | <0.001* | <0.001* | |||
| LL (°) | ||||||
| Preoperatively | 37.2 ± 16.8 | 33.0 ± 26.3 | 30.4 ± 22.0 | 0.517 | 0.296 | 0.691 |
| Postoperatively | 41.6 ± 14.0 | 37.5 ± 23.0 | 37.5 ± 23.0 | 0.457 | 0.755 | 0.657 |
| At final follow‐up | 37.6 ± 12.7 | 35.9 ± 12.7 | 36.4 ± 17.5 | 0.700 | 0.788 | 0.914 |
| p‐value | 0.004* | 0.094 | 0.417 | |||
| PI (°) | ||||||
| Preoperatively | 45.1 ± 12.6 | 52.7 ± 11.6 | 53.0 ± 7.9 | 0.020* | 0.016* | 0.924 |
| Postoperatively | 45.5 ± 12.3 | 55.1 ± 12.1 | 53.8 ± 8.0 | 0.007* | 0.024* | 0.693 |
| At final follow‐up | 44.0 ± 12.5 | 52.9 ± 11.7 | 52.6 ± 9.4 | 0.025* | 0.025* | 0.947 |
| PT (°) | ||||||
| Preoperatively | 23.7 ± 10.4 | 31.1 ± 9.8 | 32.7 ± 8.9 | 0.012* | 0.002* | 0.553* |
| Postoperatively | 20.5 ± 9.3 | 22.3 ± 9.3 | 21.6 ± 6.0 | 0.482 | 0.688 | 0.768 |
| At final follow‐up | 19.9 ± 12.0 | 23.4 ± 7.6 | 22.3 ± 6.5 | 0.274 | 0.442 | 0.725 |
| SS (°) | ||||||
| Preoperatively | 21.4 ± 7.8 | 21.6 ± 7.0 | 20.2 ± 6.9 | 0.918 | 0.585 | 0.512 |
| Postoperatively | 25.0 ± 13.5 | 32.8 ± 9.8 | 32.2 ± 9.6 | 0.027* | 0.048* | 0.864 |
| At final follow‐up | 24.1 ± 11.7 | 29.9 ± 7.3 | 30.4 ± 8.1 | 0.065 | 0.046* | 0.900 |
| SVA (mm) | ||||||
| Preoperatively | 21.2 ± 26.5 | 44.1 ± 32.9 | 46.9 ± 36.6 | 0.017* | 0.016* | 0.788 |
| Postoperatively | 17.3 ± 29.0 | 30.1 ± 26.3 | 31.7 ± 21.1 | 0.011* | 0.049* | 0.817 |
| At final follow‐up | 18.1 ± 28.5 | 30.8 ± 28.1 | 32.8 ± 20.4 | 0.035* | 0.046* | 0.728 |
| p‐value | 0.697 | 0.002* | 0.006* | |||
| Change in SVA | 3.05 ± 31.80 | 13.80 ± 23.85 | 14.11 ± 36.12 | 0.035* | 0.032* | 0.973 |
| T1PA (°) | ||||||
| Preoperatively | 26.0 ± 16.1 | 29.5 ± 16.4 | 34.7 ± 17.4 | 0.473 | 0.073 | 0.283 |
| Postoperatively | 21.0 ± 12.1 | 15.9 ± 10.6 | 20.5 ± 7.0 | 0.086 | 0.865 | 0.116 |
| At final follow‐up | 22.78 ± 17.3 | 17.5 ± 10.7 | 21.2 ± 12.4 | 0.154 | 0.661 | 0.312 |
| p‐value | 0.512 | 0.006* | 0.001* | |||
| LIV‐PSVL (mm) | ||||||
| Preoperatively | −28.4 ± 18.1 | 1.4 ± 14.5 | 9.4 ± 12.6 | <0.001* | <0.001* | 0.048* |
| Postoperatively | −3.8 ± 20.1 | 21.9 ± 19.6 | 18.7 ± 17.8 | <0.001* | <0.001* | 0.328 |
| At final follow‐up | −5.8 ± 21.0 | 21.3 ± 19.0 | 18.3 ± 15.9 | <0.001* | <0.001* | 0.425 |
| p‐value | 0.001* | <0.001* | 0.001* | |||
| ODI | ||||||
| Preoperatively | 38.2 ± 18.6 | 43.6 ± 16.5 | 44.3 ± 17.3 | 0.265 | 0.192 | 0.880 |
| At final follow‐up | 9.9 ± 8.1 | 8.3 ± 9.4 | 12.6 ± 12.4 | 0.571 | 0.338 | 0.117 |
| p‐value | <0.001* | <0.001* | <0.001* | |||
| JOA | ||||||
| Preoperatively | 18.6 ± 4.5 | 17.7 ± 4.6 | 17.1 ± 4.8 | 0.453 | 0.217 | 0.639 |
| At final follow‐up | 25.9 ± 2.1 | 27.0 ± 2.3 | 25.6 ± 3.6 | 0.154 | 0.716 | 0.062 |
| p‐value | <0.001* | <0.001* | <0.001* | |||
| VAS (back) | ||||||
| Preoperatively | 5.9 ± 1.5 | 6.0 ± 1.9 | 6.3 ± 2.1 | 0.877 | 0.459 | 0.549 |
| Postoperatively | 0.5 ± 0.9 | 0.6 ± 1.2 | 0.9 ± 1.3 | 0.815 | 0.176 | 0.252 |
| p‐value | <0.001* | <0.001* | <0.001* | |||
| VAS (leg) | ||||||
| Preoperatively | 1.5 ± 2.7 | 1.4 ± 1.9 | 1.5 ± 2.4 | 0.820 | 0.986 | 0.795 |
| At final follow‐up | 0.1 ± 0.6 | 0.1 ± 0.4 | 0.3 ± 0.9 | 0.962 | 0.346 | 0.311 |
| p‐value | 0.011* | 0.013* | 0.001* | |||
Note: Boldface values indicate p < 0.05.
Abbreviations: BMD, bone mineral density; DJF, distal junction failure; GK, general kyphosis; Grade 3/4, pedicle subtraction osteotomy and modified grade 4 osteotomy; JOA, Japanese Orthopaedic Association; LIV, lowest instrumented vertebrae; LIV‐PSVL, the distance from the center of the LIV to the posterior sacral vertical line; LL, lumbar lordosis; ODI, Oswestry disability index; OV, osteotomized vertebrae; PCO, posterior column osteotomy; PI, pelvic incidence; PT, pelvic tilt; SS, sacral slope; SSV, sagittal stable vertebra; SVA, sagittal vertical axis; T1PA, T1 pelvic angle; TK, thoracic kyphosis; TLK, thoracolumbar kyphosis; VAS, visual analogue scale.