ObjectiveTo summarize the guiding role of imaging evaluation of oblique lumbar interbody fusion (OLIF) in recent years.MethodsThe reports of OLIF surgical imaging research at home and abroad in recent years were extensively reviewed and analyzed.ResultsPreoperative imaging evaluation plays an important role in guiding the operation of OLIF, the placement of fusion Cage, the selection of indications, and the reduction of complications.ConclusionDetailed preoperative imaging evaluation can correctly estimate the indications of OLIF, and avoid the nerve, blood vessel, and muscle injuries.
ObjectiveTo summarize the research progress of ureteral injury in oblique lumbar interbody fusion (OLIF).MethodsThe literature about incidence, clinical manifestations, diagnosis, and treatment of ureteral injury complications in OLIF was reviewed.ResultsOLIF surgery poses a risk of ureteral injury because its surgical approach is anatomically adjacent to the left ureter. Ureteral injuries in OLIF are often insidious and have no specific clinical manifestations. CT urography is a common diagnostic method. The treatment of ureteral injury depends on a variety of factors such as the time of diagnosis, the location and degree of injury, and the treatment methods range from endoscopic treatment to replacement reconstruction.ConclusionSurgeons should pay attention not to damage the ureter and find the abnormality in time during OLIF. High vigilance of abnormalities is conducive to the early diagnosis of ureteral injury. Furthermore, it is important to be familiar with ureter anatomy and gentle operation to prevent ureteral injury.
ObjectiveTo investigate the correlation between CT value and Cage subsidence in patients with lumbar degenerative disease treated with stand-alone oblique lumbar interbody fusion (OLIF). MethodsThe clinical data of 35 patients with lumbar degenerative diseases treated with stand-alone OLIF between February 2016 and October 2018 were retrospectively analyzed. There were 15 males and 20 females; the age ranged from 29 to 81 years, with an average of 58.4 years. There were 39 operative segments, including 32 cases of single-segment, 2 cases of double-segment, and 1 case of three-segment. Preoperative lumbar CT was used to measure the CT values of the axial position of L1 vertebral body, the axial and sagittal positions of L1-4 vertebral body, surgical segment, and the axial position of upper and lower vertebral bodies as the bone mineral density index, and the lowest T value was recorded by dual-energy X-ray absorptiometry. The visual analogue scale (VAS) and Oswestry disability index (ODI) scores were recorded before operation and at last follow-up. At last follow-up, the lumbar interbody fusion was evaluated by X-ray films of the lumbar spine and dynamic position; the lumbar lateral X-ray film was used to measure the subsidence of the Cage, and the patients were divided into subsidence group and nonsubsidence group. The univariate analysis on age, gender, body mass index, lowest T value, CT value of vertebral body, disease type, and surgical segment was performed to initially screen the influencing factors of Cage subsidence; further the logistic regression for multi-factor analysis was used to screen fusion independent risk factors for Cage subsidence. The receiver operating characteristic (ROC) curve and area under curve (AUC) were used to analyze the CT value and the lowest T value to predict the Cage subsidence. Spearman correlation analysis was used to determine the correlation between Cage subsidence and clinical results. Results All the 35 patients were followed up 27-58 months, with an average of 38.7 months. At last follow-up, the VAS and ODI scores were significantly decreased when compared with preoperative scores (t=32.850, P=0.000; t=31.731, P=0.000). No recurrent lower extremity radiculopathy occurred and no patient required revision surgery. Twenty-seven cases (77.1%) had no Cage subsidence (nonsubsidence group); 8 cases (22.9%) had at least radiographic evidence of Cage subsidence, the average distance of Cage subsidence was 2.2 mm (range, 1.1-4.2 mm) (subsidence group). At last follow-up, there was 1 case of fusion failure both in the subsidence group and the nonsubsidence group, there was no significant difference in the interbody fusion rate (96.3% vs. 87.5%) between two groups (P=0.410). Univariate analysis showed that the CT value of vertebral body (L1 axial position, L1-4 axial and sagittal positions, surgical segment, and upper and lower vertebral bodies axial positions) and the lowest T value were the influencing factors of Cage subsidence (P<0.05). According to ROC curve analysis, compared with AUC of the lowest T value [0.738, 95%CI (0.540, 0.936)], the AUC of the L1-4 axis CT value was 0.850 [95%CI (0.715, 0.984)], which could more effectively predict Cage subsidence. Multivariate analysis showed that the CT value of L1-4 axis was an independent risk factor for Cage subsidence (P<0.05). Conclusion The CT value measurement of the vertebral body based on lumbar spine CT before stand-alone OLIF can predict the Cage subsidence. Patients with low CT values of the lumbar spine have a higher risk of Cage subsidence. However, the Cage subsidence do not lead to adverse clinical results.