Meta analysis of effects on spinal cord protection and safety of changes in spinal cord blood flow(SCBF) caused by spinal osteotomy

English Keywords:Spinal osteotomy  Spinal deformity  Spinal shortening  Spinal cord blood flow  Spinal cord evoked potential  Meta analysis

English Abstract:

  【Abstract】 Objectives: To systematically evaluate the effects of spinal osteotomy and spinal cord blood flow(SCBF) on the spinal cord, and to explore the safe range of osteotomy. Methods: The relevant research literatures on spinal osteotomy shortening and SCBF in CNKI, Wanfang, VIP, PubMed, Cochrane Library, EMBASE and CBM databases published before May 2024 were searched by computer. Two researchers independently conducted literature screening and extracted data(research design, sample size, and outcome indicators). The quality of the included literatures was evaluated by using the improved Jadad score scale and Newcastle-Ottawa scale(NOS) score. The Revman 5.3 software was used for meta-analysis. Results: A total of 8 literatures were included, and the risk of the included literatures mainly came from the allocation hiding and outcome blind methods after evaluated with the Cochrane risk bias assessment tool; The Jadad scale scores of the 6 randomized controlled studies and the NOS scores of the 2 cohort studies were all≥5. A total of 170 subjects were included, including 91 dogs, 50 rabbits, and 29 clinical patients; In the animal experiments of dogs, the SCBF increased when the spinal vertebrae were shortened by 2/4 compared with 1/3 or 1/4[OR= -24.10, 95%CI(-35.96, -12.23), Z=3.98, P<0.0001]; The SCBF in dogs decreased when the spinal vertebrae were shortened by 2/3 or 3/4 compared with 2/4[OR=44.63, 95%CI(19.16, 70.09), Z=3.43, P=0.0006]; Spinal cord evoked potentials(SCEP) was significantly abnormal when spinal vertebrae shortening was 2/3 or 3/4 compared with 1/3 or 1/4[OR=0.03, 95%CI(0.00, 0.21), Z=3.55, P=0.004]; The dural sac tortuous angle increased significantly when the spinal vertebrae shortening in rabbits was more than 2/4[OR=53.51, 95%CI(17.92, 89.10), Z=2.95, P=0.003], which led to a sharp decrease in SCBF, and the difference was statistically significant. In clinical studies, the SCBF after spinal vertebrae shortening of less than 2/4, that was, about 2/4 of the resection space, was slightly higher than that after vertebral column resection(VCR) [OR=43.81, 95%CI(20.40, 67.21), Z=3.67, P=0.002], and the difference was statistically significant. Conclusions: In animal experiments in dogs and rabbits and clinical studies, spinal vertebrae shortening of less than 2/4 is the safe range of osteotomy; In the animal experiment of dogs, when the shortening is more than 2/3 or 3/4, it will lead to a sharp decrease in SCBF and cause obvious SCEP abnormalities.