Department of Orthopaedics, The First Affiliated Hospital of Jinan University, Guangzhou, China.
Spine Division, Department of Orthopaedics, The First Medical Center, Chinese People's Liberation Army General Hospital, Beijing, China.
Orthop Surg. 2020 Dec;12(6):1685-1692. doi: 10.1111/os.12805. Epub 2020 Sep 21.
To investigate the compensatory mechanism of maintaining the sagittal balance in degenerative lumbar scoliosis patients with different pelvic incidence (PI).
This was a retrospective imaging observation study. Patients in our department with degenerative lumbar scoliosis between 2017 and 2019 were reviewed. A total of 36 patients were eligible and included in the present study. The average age of those patients was 64.22 years, including 8 men and 28 women. The coronal and sagittal parameters were measured on full-length spine X-ray film, including globe kyphosis (GK), lumber lordosis (LL), thoracolumbar kyphosis (TLK), thoracic kyphosis (TK), sagittal vertical axis (SVA), sagittal shift angle, Cobb angle, coronal shift angle, and vertebra. The anterior pelvic plane angle (APPA) and pelvic parameters were also measured, including the pelvic tilt (PT), the PI, and the sacral slope (SS). PI-LL, LL-SS, and GK-SS were calculated. Traditional pelvic tilt was also calculated using the following formula: cPT = PI × 0.37-7. These patients were divided into two groups according to their PI values. The patients' PI value in Group 1 was smaller than 50°. The patients' PI value in Group 2 was equal to or larger than 50°.
These patients' SS, PT, PI, LL, TLK, TK, and GK were 28.70° ± 11.36°, 23.28° ± 6.55°, 52.00° ± 11.03°, 31.66° ± 14.12°, 12.12° ± 14.9°, 17.81° ± 13.53°, and -13.17° ± 16.27°. The sagittal shift angle, the APPA, the Cobb angle, the coronal shift angle, vertebra, PI-LL, cPT, APPA-4, LL-SS, and GK-SS were 4.38° ± 5.75°, -12.55° ± 8.83°, 30.03° ± 12.59°, 2.40° ± 2.13°, 4.08 ± 0.93, 19.86° ± 10.97°, 12.35° ± 4.55°, -8.30° ± 9.07°, 3.30° ± 8.82°, and 15.53° ± 9.83°, respectively. There was no significant difference between PT and cPT + APPA-4 or between cPT and PT-APPA+4. There was significant difference between PT and cPT + APPA or between cPT and PT-APPA. This demonstrated that the APPA-4 is reliable as degree of the pelvic sagittal retroversion. There were significant differences in SS, PI, LL, TLK, GK, APPA, PT-APPA, PT-APPA+4, cPT, and APPA-4 between Group 1 and Group 2. There were no significant differences in PT, TK, sagittal shift angle, SVA, Cobb angle, coronal shift angle, vertebra number, PI-LL, cPT + APPA, cPT + APPA-4, LL-SS, and GK-SS between Group 1 and Group 2. The Pearson tests showed that PI-LL had significant correlations with TK, LL, sagittal shift angle, SVA, and LL-SS. There was no significant correlation between PI-LL and Cobb angle, GK, TLK, APPA, vertebra, Coronal Shift Angle, or GK-SS.
The APPA-4 is reliable as degree of the pelvic sagittal retroversion. In degenerative lumbar scoliosis, patients with smaller PI tended to rely more on the pelvic retroversion to maintain the sagittal balance than patients with larger PI, or patients with smaller PI were likely to start up the pelvic retroversion compensatory mechanism earlier than the patients with larger PI.
研究不同骨盆入射角（PI）的退变性腰椎侧凸患者维持矢状位平衡的代偿机制。
这是一项回顾性影像学观察研究。回顾了 2017 年至 2019 年在我院就诊的退变性腰椎侧凸患者。共有 36 名患者符合条件并纳入本研究。这些患者的平均年龄为 64.22 岁，包括 8 名男性和 28 名女性。在全长脊柱 X 线片上测量冠状和矢状参数，包括球型后凸（GK）、腰椎前凸（LL）、胸腰椎后凸（TLK）、胸椎后凸（TK）、矢状垂直轴（SVA）、矢状移位角、Cobb 角、冠状移位角和椎体。还测量了骨盆前平面角（APPA）和骨盆参数，包括骨盆倾斜角（PT）、PI 和骶骨倾斜角（SS）。计算 PI-LL、LL-SS 和 GK-SS。还使用以下公式计算传统的骨盆倾斜角：cPT = PI×0.37-7。根据 PI 值将这些患者分为两组。组 1 患者的 PI 值小于 50°，组 2 患者的 PI 值等于或大于 50°。
这些患者的 SS、PT、PI、LL、TLK、TK 和 GK 分别为 28.70°±11.36°、23.28°±6.55°、52.00°±11.03°、31.66°±14.12°、12.12°±14.9°、17.81°±13.53°和-13.17°±16.27°。矢状移位角、APPA、Cobb 角、冠状移位角、椎体、PI-LL、cPT、APPA-4、LL-SS 和 GK-SS 分别为 4.38°±5.75°、-12.55°±8.83°、30.03°±12.59°、2.40°±2.13°、4.08°±0.93°、19.86°±10.97°、12.35°±4.55°、-8.30°±9.07°、3.30°±8.82°和 15.53°±9.83°。PT 和 cPT+APPA-4 或 cPT 和 PT-APPA+4 之间没有统计学差异。PT 和 cPT+APPA 或 cPT 和 PT-APPA 之间存在显著差异。这表明 APPA-4 作为骨盆矢状后倾程度是可靠的。组 1 和组 2 之间在 SS、PI、LL、TLK、GK、APPA、PT-APPA、PT-APPA+4、cPT 和 APPA-4 方面存在显著差异。组 1 和组 2 之间在 PT、TK、矢状移位角、SVA、Cobb 角、冠状移位角、椎体数量、PI-LL、cPT+APPA、cPT+APPA-4、LL-SS 和 GK-SS 方面无显著差异。Pearson 检验显示 PI-LL 与 TK、LL、矢状移位角、SVA 和 LL-SS 有显著相关性。PI-LL 与 Cobb 角、GK、TLK、APPA、椎体、冠状移位角或 GK-SS 无显著相关性。
APPA-4 作为骨盆矢状后倾程度是可靠的。在退变性腰椎侧凸中，PI 较小的患者倾向于通过骨盆后倾来维持矢状位平衡，而 PI 较大的患者则更多地依赖腰椎前凸来维持矢状位平衡，或者 PI 较小的患者可能比 PI 较大的患者更早地启动骨盆后倾补偿机制。
