Correlation Study And Risk Factors Analysis Of Fusion Cage Subsidence And Clinical Efficacy After Stand-alone OLIF Surgery

Objective: Nowadays,OLIF technology has been widely used for the treatment of a variety of lumbar degenerative diseases.The purpose of this study was to observe the clinical efficacy of Stand-Alone OLIF in the treatment of lumbar degenerative diseases and explore the related risk factors of cage settlement after surgery,so as to provide a valuable reference for clinical treatment.Methods: A total of 84 patients(36 males and 48 females)who received Stand-Alone OLIF surgery in Yijishan Hospital of Southern Anhui Medical College from July 2017 to December 2019 were included.The general data of included patients were counted(including gender,age,BMI,BMD,past medical history,hospital stay,cage specification,intraoperative blood loss,operation duration,and cage settlement or not).The visual analogue scale for pain(VAS)and the Auschwitz Disability Assessment Index(ODI)were used to evaluate the efficacy.Observe the differences of curative effects before and after operation among all patients;To compare the differences of surgical efficacy between patients with postoperative fusion cage subsidence and patients without subsidence.To compare the differences in surgical efficacy between patients with mild postoperative fusion cage subsidence and patients with severe postoperative fusion cage subsidence.Finally,binary Logistic regression analysis was used to screen the risk factors for postoperative fusion cage settlement.Results: All 84 patients underwent Stand-Alone OLIF surgery,including 36 male patients and 48 female patients,with the average age of 61.21 9.49 years old,average BMI of24.99±2.97 kg/m2,and average BMD of-0.77 1.18 g/cm3.The preoperative VAS and ODI scores of all patients were 4.96 1.06 and 28.50 6.48,respectively,and the last postoperative follow-up improvements were 2.38 0.84 and 14.36 3.46,respectively(p<0.05).The last follow-up VAS and ODI of patients in the subsidence group were 3.09 0.79 and 17.96 2.62 respectively,while those of patients in the non-subsidence group were 2.11 0.69 and 13.002.67 respectively.There was a significant difference in clinical efficacy between the two groups,while the efficacy of patients in the subsidence group was poorer,with statistical significance(p<0.05).The last follow-up VAS and ODI values in the mild settlement group were 2.82 0.64 and 16.94 2.19,respectively,while those in the severe settlement group were3.83 0.75 and 20.83 1.17,respectively.The clinical efficacy of patients with mild settlement is more accurate than that of patients with moderate settlement,and the difference is statistically significant(p<0.05).The results of binary Logistic regression analysis showed that BMD was negatively correlated with cage settlement,and BMI was positively correlated with cage settlement.The intervertebral cage with an external insertion height of14 mm was an independent risk factor for cage settlement(p<0.05).Conclusion: 1.The clinical efficacy of Stand-Alone OLIF in the treatment of lumbar degenerative diseases is exact.2.There is a negative correlation between the degree of cage subsidence and clinical efficacy.The milder the degree of cage subsidence,the more accurate the clinical efficacy will be.3.BMD,BMI and the placement of a cage with a height of 14 mm are the independent risk factors for cage settlement after Stand-Alone OLIF surgery.Clinicians should improve various examinations before surgery to reduce the incidence of cage settlement.