Table 1.
Baseline characteristics.
Table 2.
Radiographic parameters preoperatively, postoperatively, and at last follow-up.
Table 3.
Correlations between postoperative cervical lordosis, T1 slope, and other radiographic parameters.
Table 4.
Multilinear regression analysis.
Table 5.
Correlations between last follow-up cervical lordosis, T1 slope, thoracic kyphosis and other radiographic parameters.
Fig 1.
Correlations between Post cervical parameters and the various spinopelvic parameters.
Post CL and Post T1S were more significantly affected by the amount of LL correction than by the changes in Post LL, Post TK and Post PI-LL.
Fig 2.
Correlations between Last cervical parameters and the various spinopelvic parameters.
Last CL was affected by Last T1S, and Last T1S was affected by Last TK, but both parameters were not significantly associated with Post and Last C7SVA, Last LL and Last PI-LL. Additionally, there was a significant association between Last TK and Post PI-LL.
Fig 3.
A 62-year-old female with degenerative sagittal imbalance and cervical hyperlordosis (C7SVA + 293mm, TK -4°, LL 21°, PT 29°, PI 51°, CL -30°, T1S 45°) underwent PSO on L2, PLIF on L4-5, ALIF on L5-S1, and posterior spinal fusion from T10 to S1 with sacropelvic fixation and accessory rod fixation. Optimal sagittal alignment was obtained after correction (C7SVA -48mm, TK 12°, LL -65°, PT 5°), but cervical kyphosis occurred (CL +16°, T1S 10°). A relatively large amount of LL correction due to the high PI led to a drastic reduction in Post C7SVA and subsequent reduction of Post T1S and CL. Radiograph at 2 years postoperatively showed a well-maintained optimal sagittal alignment with restoration of cervical lordosis (C7SVA -24mm, TK 27°, LL -66°, PT 5°, CL -5°, T1S 15°). TK increased to achieve spinopelvic harmony resulting from the postoperative difference in LL relative to PI. This modification in TK led to gradual optimal changes in T1S and CL over time.