Classification of the lumbosacral triangle and its application in endoscopic surgery for L 5S 1
10.3760/cma.j.cn121113-20240225-00114
- VernacularTitle:腰骶三角分型的建立及在L 5S 1内镜手术中的应用
- Author:
Baoshan XU
1
;
Jie LI
;
Tianyi LI
;
Lilong DU
;
Haiwei XU
;
Kaihui ZHANG
;
Tongxing ZHANG
Author Information
1. 天津市天津医院微创脊柱外科，天津 300211
- Keywords:
Spine;
Anatomy;
Classification;
Minimally invasive surgical procedures
- From:
Chinese Journal of Orthopaedics
2024;44(12):796-802
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To establish a lumbosacral triangle (composed of L 5 transverse process, S 1 superior articular process, sacral ala and iliac crest) classification and to guide L 5S 1 endoscopic surgery. Methods:A total of 647 patients with low back pain who admitted to Tianjin Hospital from January 2016 to October 2018 were retrospectively analyzed, including 315 males and 332 females, aged 42.9±15.1 years (range, 19-74 years). The L 5 transverse process sacral distance (TSD), inter trans-verse process length (ITL), interlaminar width (ILW), interlaminar height (ILH), iliosacral angle (ISA), iliac crest height (IH), intervertebral space height (ISH), intervertebral foramen height (IFH), and intervertebral foramen width (IFW) were measured based on lumbar spine anterior-posterior and lateral radiographs. Spearman correlation analysis and hierarchical cluster analysis were used to establish the lumbosacral triangle classification. A total of 822 patients underwent endoscopic L 5S 1 surgery based on lumbosacral triangle classification guidance and verification in Tianjin Hospital from January 2020 to December 2022, including 421 males and 401 females, aged 45.1±16.7 years (range, 15-79 years). The visual analogue scale (VAS) and Oswestry disability index (ODI) were compared before and after surgery, and the Macnab criteria were used to assess surgical outcomes. Results:Spearman correlation analysis showed positive correlations between IH and ISA ( r=0.75, P<0.001), IFH and IFW ( r=0.60, P<0.001), TSD and IFH ( r=0.53, P<0.001), and TSD and IFW ( r=0.40, P<0.001). There was a negative correlation between TSD and IH ( r=-0.46, P<0.001), TSD and ISA ( r=-0.42, P<0.001), IFW and ISA ( r=-0.41, P<0.001), IFW and IH ( r=-0.50, P<0.001), IFH and IH ( r=-0.42, P<0.001). According to Spearman correlation analysis, hierarchical cluster analysis and receiver operating characteristic curve, lumbosacral angle was divided into three types: Type 1, L5 transverse process overlapped with sacral alar; Type 2, 07 mm. Based on lumbosacral triangle classification, different endoscopic techniques were used at L5S1 in 822 patients, including interlaminar approach single-axis endoscopy, trans-foraminal approach single-axis endoscopy, trans-foraminal fenestration approach mobile microendoscopy and unilateral biportal endoscopy, the VAS and ODI of all the patients decreased than those preoperative in immediate postoperative period, half a year postoperative period and the final follow up, and the difference was statistically significant ( P<0.05). At the last follow-up, the Macnab score was excellent in 278 cases, good in 475 cases, and fair in 69 cases, with an excellent and good rate of 91.6% (753/822). Conclusion:Lumbosacral triangle classification is simple and practical, and can effectively guide L5S1 endoscopic surgery.
