Safety And Efficacy Of Decompressive Surgery By Laminectomy Combined With Durotomy In The Treatment Of Acute Traumatic Cervical Spinal Cord Injury

Objective:Our team recently studied the relationship between the nature,extent and prognosis of preoperative MRI in 26 patients with acute traumatic cervical spinal cord injury(ATCSCI).At the same time,Codman detection system was used to detect the changes of intraspinal pressure(ISP)after laminectomy and decompression of durotomy.Laminectomy and durotomy decompression were used to verify the safety and efficacy of decompression in the treatment of ATCSCI.Methods: from June 2017 to March 2019,26 patients with ATCSCI were analyzed retrospectively.Before the operation,the X radiographs,CT and MRI of cervical spine were examined.The vertical length of spinal cord edema(T2WI high signal)and spinal cord hemorrhage(T2WI low signal)were measured by computer.DTI and DTT were used for the first time to detect the shape of spinal cord white matter fiber bundle and measure of spinal cord white matter fiber volume(WMFV).The intraoperative ISP was measured in 8 patients and monitored continuously for 1 week.26 cases were treated with durotomy and duroplasty after posterior extensive laminectomy surgery.The American Spinal Injury Association(ASIA)grades and scores were recorded before and at the last follow-up.A paired t-test was used to compare the ASIA motor score(AMS)before and after the last follow-up.Spearman correlation coefficient was used to evaluate the correlation between the WMFV,the vertical length of spinal cord edema and the vertical length of spinal cord hemorrhage with AMS.Result:1.12 cases were found fracture or dislocation of cervical spine on CT scan(group A),14 cases were not found obvious fracture and dislocation damage(group B).Extensive edema of spinal cord was found in 15 cases(group 1)and suspected hemorrhage of spinal cord with extensive edema in 11 cases(group 2).The AMS of group B preoperative and at last follow-up was significantly higher than that of group A(P<0.05).The AMS of group 2 preoperative and at last follow-up was significantly higher than that of group 1(P<0.05).There was a moderate negative correlation between the vertical length of preoperative spinal cord edema and AMS(ρ=-0.63,P < 0.05)and a moderate negative correlation between the vertical length of preoperative spinal cord hemorrhage and AMS(ρ=-0.77,P < 0.05)at the last follow-up.2.The DTT results of 26 cases of spinal cord injury showed that there were four types of spinal cord injury: type A1: complete rupture of spinal cord fiber bundle.Type A2: partial rupture of spinal cord fiber bundle.Type B: most of the fibrous tracts of the spinal cord were preserved with significant compression or abnormal fiber conduction direction.Type C:the fiber bundle of spinal cord is basically complete with slight compression or sparseness.The preoperative physical examination of type A1(n = 5)and type A2(n = 5)patients was complete injury.At the last follow-up,we found that the ASIA grade or motor sensory score of type A2 patients were improved in varying degrees.There was no significant change in ASIA grade and motor sensory score in type A1 patients.The volume of white matter fiber bundle was positively correlated with AMS(ρ=0.81,P < 0.05).This study proposes a novel classification of spinal cord injury based on DTI and DTT.3.26 cases of cerebrospinal fluid(CSF)pulsation were not recovered after laminectomy.After durotomy,CSF pulsation recovered in 23 cases.In 8 cases of ISP monitor,the ISP was between 8-23 mm Hg after laminectomy,with an average of 14 mm Hg.The ISP was between 3-14 mm Hg after durotomy and duroplasty,with an average of 7.5 mm Hg.It was kept between 5-17 mm Hg after surgery,with an average of 9.6mm Hg.Conclusion:1.The extent of spinal cord edema and hemorrhage on preoperative MRI can preliminarily predict the prognosis of patients.2.In clinic,the recovery of part cases of ASIA A may be due to the retention of part of the white matter fiber bundle,while the failure of some ASIA A is due to the complete rupture of the white matter fiber bundle.3.It can evaluate the spinal cord injury more intuitively and systematically by detecting the contusion and hemorrhage of gray matter by conventional MRI and the white matter damage by DTI.4.ISP monitoring is a feasible method of spinal cord injury pressure monitoring.Bone decompression alone may not be sufficient for spinal cord injury.Durotomy is helpful for the complete decompression of spinal cord and the improvement of CSF circulation.