Surgical strategy for lumbar degenerative diseases with segment instability between upper instrument vertebra and adjacent upper vertebra
10.3760/cma.j.cn121113-20231007-00221
- VernacularTitle:责任节段上位固定椎与邻近上位椎体不稳的腰椎退行性疾病的手术策略
- Author:
Xi LI
1
;
Lei LIU
;
Zhe ZHANG
;
Yuzhu XU
;
Peiyang WANG
;
Xiaolong LI
;
Guozhen LIU
;
Lele ZHANG
;
Zhiyang XIE
;
Yuao TAO
;
Pan FAN
;
Yuntao WANG
Author Information
1. 东南大学医学院，南京 210009
- Keywords:
Lumbar vertebrae;
Intervertebral disc degeneration;
Spinal fusion;
Segmental instability;
Sagittal angulation;
Sagittal translation
- From:
Chinese Journal of Orthopaedics
2024;44(10):658-668
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To summarize long-term clinical follow-up results of segment instability between the upper instrumented vertebra (UIV) and the adjacent upper vertebra (UIV+1) and to establish the optimal timing for surgery for UIV+1.Methods:A retrospective analysis was conducted on 265 patients with lumbar degenerative diseases who underwent transforaminal lumbar interbody fusion (TLIF) surgery at the Department of Spinal Surgery, Zhongda Hospital, from January 2014 to December 2018. The cohort included 119 male and 146 female patients, with an average age of 64.93 years (range: 32-86 years). Preoperative dynamic imaging measured sagittal angulation (SA) and sagittal translation (ST) of the UIV+1/UIV segment. Patients with SA>10° or ST>2 mm were categorized into the unstable group, further divided into the unstable non-fusion group and the unstable fusion group based on whether UIV+1 expansion fusion was performed. The remaining patients were classified into the stable group. Imaging indicators, Visual Analogue Scale (VAS) scores, Oswestry disability index (ODI) scores, and Japanese Orthopaedic Association (JOA) scores were compared among the groups, with JOA improvement rates calculated to assess clinical efficacy. Pearson correlation coefficient analysis was employed to examine correlations between preoperative imaging indicators and final follow-up JOA improvement rates. Receiver Operating Characteristic (ROC) curves and the maximum Youden index were utilized to determine thresholds for preoperative SA and ST.Results:The follow-up duration for all patients was 73.53±12.92 months (range: 61-108 months). The stable group (124 cases) included 61 males and 63 females, aged 64.31±9.83 years (range: 44-82 years). The unstable non-fusion group (59 cases) included 22 males and 37 females, aged 65.76±11.01 years (range: 32-86 years). The unstable fusion group (82 cases) included 36 males and 46 females, aged 65.26±8.68 years (range: 47-80 years). At the last follow-up, the unstable non-fusion group exhibited ΔSA 0.90°±1.97° and ΔST 0.77±1.27 mm, both significantly higher than the stable group's ΔSA 0.25°±1.57° and ΔST 0.34±0.34 mm ( t=3.564, P<0.001; t=2.311, P=0.022). Clinical improvements were lower in the unstable non-fusion group compared to the other two groups: VAS (2.28±0.83), ODI (5.91%±3.46%), JOA (24.11±1.78), with a JOA improvement rate of 60%. The stable group showed VAS (1.51±0.69), ODI (3.71%±1.75%), JOA (27.33±1.91), with a JOA improvement rate of 83%. The unstable fusion group had VAS (1.46±0.83), ODI (3.46%±1.81%), JOA (26.48±1.66), with a JOA improvement rate of 78%. These differences were statistically significant ( F=32.117, P<0.001; F=24.827, P<0.001; F=92.658, P<0.001; F=93.341, P<0.001). The JOA improvement rate was negatively correlated with preoperative SA ( r=-0.363, P<0.001) to a low extent, and with preoperative ST ( r=-0.596, P<0.001) to a moderate extent. ROC curve analysis determined the preoperative SA threshold as 11.5° and the preoperative ST threshold as 1.85 mm. Conclusion:Pre-existing instability of the responsible segment UIV and UIV+1 (SA>10° or ST>2 mm) may worsen during long-term follow-up after TLIF. When preoperative SA exceeds 11.5° and ST exceeds 1.85 mm between UIV and UIV+1, performing an extended fusion involving UIV+1 can ensure surgical efficacy over long-term follow-up.
