Objective To compare the effectiveness between unilateral biportal endoscopic lumbar interbody fusion (ULIF) and endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) in treatment of lumbar spinal stenosis combined with intervertebral disc herniation. Methods A clinical data of 64 patients with lumbar spinal stenosis and intervertebral disc herniation, who were admitted between April 2020 and November 2021 and met the selection criteria, was retrospectively analyzed. Among them, 30 patients were treated with ULIF (ULIF group) and 34 patients with Endo-TLIF (Endo-TLIF group). There was no significant difference in baseline data such as gender, age, disease duration, lesion segment, preoperative visual analogue scale (VAS) score of low back pain and leg pain, Oswestry disability index (ODI), spinal canal area, and intervertebral space height between the two groups (P>0.05). The operation time, intraoperative blood loss, hospital stays, and postoperative complications were compared between the two groups, as well as the VAS scores of low back pain and leg pain, ODI, and imaging measurement indicators (spinal canal area, intervertebral bone graft area, intervertebral space height, and degree of intervertebral fusion according to modified Brantigan score). Results Compared with the Endo-TLIF group, the ULIF group had shorter operation time, but had more intraoperative blood loss and longer hospital stays, with significant differences (P<0.05). The cerebrospinal fluid leakage occurred in 2 cases of Endo-TLIF group and 1 case of ULIF group, and no other complication occurred. There was no significant difference in the incidence of complications between the two groups (P>0.05). All patients in the two groups were followed up 12 months. The VAS scores of lower back pain and leg pain and ODI in the two groups significantly improved when compared with those before operation (P<0.05), and there was no significant difference between different time points after operation (P>0.05). And there was no significant difference between the two groups at each time point after operation (P>0.05). Imaging examination showed that there was no significant difference between the two groups in the change of spinal canal area, the change of intervertebral space height, and intervertebral fusion rate at 6 and 12 months (P>0.05). The intervertebral bone graft area in the ULIF group was significantly larger than that in the Endo-TLIF group (P<0.05). ConclusionFor the patients with lumbar spinal stenosis combined with intervertebral disc herniation, ULIF not only achieves similar effectiveness as Endo-TLIF, but also has advantages such as higher decompression efficiency, flexible surgical instrument operation, more thorough intraoperative intervertebral space management, and shorter operation time.
Objective To compare the effectiveness of O-arm navigation and ultrasound volume navigation (UVN) in guiding screw placement during minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) surgery. Methods Sixty patients who underwent MIS-TLIF surgery for lumbar disc herniation between June 2022 and June 2023 and met the selection criteria were included in the study. They were randomly assigned to group A (screw placement guided by UVN during MIS-TLIF) or group B (screw placement guided by O-arm navigation during MIS-TLIF), with 30 cases in each group. There was no significant difference in baseline data, including gender, age, body mass index, and surgical segment, between the two groups (P>0.05). Intraoperative data, including average single screw placement time, total radiation dose, and average single screw effective radiation dose, were recorded and calculated. Postoperatively, X-ray film and CT scans were performed at 10 days to evaluate screw placement accuracy and assess facet joint violation. Pearson correlation and Spearman correlation analyses were used to observe the relationship between the studied parameters (average single screw placement time and screw placement accuracy grading) and BMI. Results The average single screw placement time in group B was significantly shorter than that in group A, and the total radiation dose of single segment and multi-segment and the average single screw effective radiation dose in group B were significantly higher than those in group A (P<0.05). There was no significant difference in the total radiation dose between single segment and multiple segments in group B (P>0.05), while the total radiation dose of multiple segments was significantly higher than that of single segment in group A (P<0.05). No significant difference was found in the accuracy of screw implantation between the two groups (P>0.05). In both groups, the grade 1 and grade 2 screws broke through the outer wall of the pedicle, and no screw broke through the inner wall of the pedicle. There was no significant difference in the rate of facet joint violation between the two groups (P>0.05). In group A, both the average single screw placement time and screw placement accuracy grading were positively correlated with BMI (r=0.677, P<0.001; r=0.222, P=0.012), while in group B, neither of them was correlated with BMI (r=0.224, P=0.233; r=0.034, P=0.697). Conclusion UVN-guided screw placement in MIS-TLIF surgery demonstrates comparable efficiency, visualization, and accuracy to O-arm navigation, while significantly reducing radiation exposure. However, it may be influenced by factors such as obesity, which poses certain limitations.
Objective To explore the clinical application value of the spinal robot-assisted surgical system in mild to moderate lumbar spondylolisthesis and evaluate the accuracy of its implantation. Methods The clinical data of 56 patients with Meyerding grade Ⅰ or Ⅱ lumbar spondylolisthesis who underwent minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) between January 2017 and December 2017 were retrospectively analysed. Among them, 28 cases were preoperatively planned with robotic arm and percutaneous pedicle screw placement according to preoperative planning (group A); the other 28 cases underwent fluoroscopy-guided percutaneous pedicle screw placement (group B). There was no significant difference in gender, age, body mass index, slippage type, Meyerding grade, and surgical segmental distribution between the two groups (P>0.05). The screw insertion angle was measured by CT, the accuracy of screw implantation was evaluated by Neo’s criteria, and the invasion of superior articular process was evaluated by Babu’s method. Results One hundred and twelve screws were implanted in the two groups respectively, 5 screws (4.5%) in group A and 26 screws (23.2%) in group B penetrated the lateral wall of pedicle, and the difference was significant (χ2=9.157, P=0.002); the accuracy of nail implantation was assessed according to Neo’s criteria, the results were 107 screws of degree 0, 3 of degree 1, 2 of degree 2 in group A, and 86 screws of degree 0, 16 of degree 1, 6 of degree 2, 4 of degree 3 in group B, showing significant difference between the two groups (Z=4.915, P=0.031). In group B, 20 (17.9%) screws penetrated the superior articular process, while in group A, 80 screws were removed from the decompression side, and only 3 (3.8%) screws penetrated the superior articular process. According to Babu’s method, the degree of screw penetration into the facet joint was assessed. The results were 77 screws of grade 0, 2 of grade 1, 1 of grade 2 in group A, and 92 screws of grade 0, 13 of grade 1, 4 of grade 2, 3 of grade 3 in group B, showing significant difference between the two groups (Z=7.814, P=0.029). The screw insertion angles of groups A and B were (23.5±6.6)° and (18.1±7.5)° respectively, showing significant difference (t=3.100, P=0.003). Conclusion Compared to fluoroscopy-guided percutaneous pedicle screw placement, robot-assisted percutaneous pedicle screw placement has the advantages such as greater accuracy, lower incidence of screw penetration of the pedicle wall and invasion of the facet joints, and has a better screw insertion angle. Combined with MIS-TLIF, robot-assisted percutaneous pedicle screw placement is an effective minimally invasive treatment for lumbar spondylolisthesis.
ObjectiveTo investigate the clinical results and complication prevention of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in the treatment of single-segment severe lumbar spinal stenosis (LSS).MethodsThe clinical data of 112 patients with severe LSS treated with MIS-TLIF between January 2010 and January 2017 were retrospectively analyzed. There were 43 males and 69 females, aged 52-81 years, with an average age of 65.3 years. The disease duration ranged from 4 to 126 months, with an average of 10.5 months. Clinical manifestations: 104 cases of low back pain, 91 cases of nervous intermittent claudication of both lower limbs, 21 cases of unilateral nerve root pain and/or numbness, and 5 cases of cauda equina nerve injury. The 112 cases were all severe central spinal stenosis, including 32 cases with lateral recess stenosis, 20 cases with foramen stenosis, 9 cases with ossification of ligamentum flavum, 38 cases with disc herniation; 14 cases with two complications and 5 cases with three. Stenosis segment: L3, 4 in 6 cases, L4, 5 in 89 cases, and L5, S1 in 17 cases. Surgical methods included bilateral decompression through bilateral approach (60 cases), bilateral decompression through unilateral approach (15 cases), and unilateral decompression (37 cases). The operation time, intraoperative blood loss, visual analogue scale (VAS) score of low back pain and leg pain, Oswestry disability index (ODI) score, fusion rate, and surgical complications were recorded. At last follow-up, the lumbar fusion was evaluated by Bridwell method, grades Ⅰ and Ⅱ were expressed as fusion.ResultsThe operation time was 83-186 minutes (mean, 126.8 minutes), and the intraoperative blood loss was 65-630 mL (mean, 163.1 mL). All the 112 patients were followed up 25-49 months, with an average of 35.1 months. The VAS score of low back pain and leg pain and ODI score at each time point after operation were significantly improved when compared with preoperative scores (P<0.05). There was no significant difference between the VAS score of low back pain and leg pain and ODI score at the other time points except 1 month after operation (P<0.05). At last follow-up, 2 cases of cauda equina nerve injury recovered and 3 cases partially recovered. According to Bridwell classification criteria, 58 cases were grade Ⅰ, 47 cases were grade Ⅱ, and 7 cases were grade Ⅲ. The fusion rate was 93.8%. Perioperative complications included 5 cases of incision complications (superficial infection in 3 cases, hematoma formation in 2 cases), 19 cases of internal fixator complications (intraoperative end plate fracture in 8 cases, fusion cage sinking in 11 cases at last follow-up), and 15 cases of neurological complications (dural sac tear in 10 cases, transient neurological symptoms of lower extremities aggravated in 5 cases). Conclusion MIS-TLIF treatment of single-level severe LSS can achieve good clinical results, while there is a risk of serious complications. Full understanding of the clinical and imaging features of the disease and reasonable and careful operation are helpful to control the occurrence of cauda equina nerve damage.
Objective To investigate the feasibility and clinical outcomes of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) using unilateral incision and internal fixation of pedicle screws and a translaminar facet screw for dural-level lumbar degenerative disease. Methods Between January 2010 and January 2012, 19 patients with dural-level lumbar degenerative disease was treated, including 7 males and 12 females with an average age of 50.4 years (range, 22-68 years) and a median disease duration of 37 months (range, 8 months to 15 years). The operated segments included L3-5 in 6 cases and L4-S1 in 13 cases. MIS-TLIF was performed by unilateral incision, and then pedicle screws and a translaminar facet screw were used for internal fixation. Results Operations were successfully performed in all cases. The mean operation time was 158 minutes; the mean intraoperative blood loss was 156 mL; the mean length of incision was 42 mm; the mean postoperative ambulation time was 35 hours; the mean hospitalization time was 4.1 days; and the mean length of translaminar facet screw was 51 mm. All the wounds healed by first intention. No complication occurred in the others except 1 case of dural tear. The patients were followed up 12-24 months (mean, 17.1 months). The visual analogue scale (VAS) scores for back and leg pain and Oswestry disability index (ODI) scores at postoperation were significantly improved when compared with preoperative ones (P lt; 0.05). The symptom disappeared gradually. The postoperative X-ray images showed that the internal fixations were in good position; all facets screws penetrated through the base of spinous process, laminar, and facets joint; of the screws, 2 (5.3%) facets screws penetrated lateral laminar, and 1 (1.8%) pedicle screw penetrated out of pedicle of vertebral arch, but no symptom of nerve injury was seen. The CT scan and three-dimensional reconstruction at postoperative 12th month showed good interbody fusion; and based on the Bridwell’s interbody fusion grading system, 11 cases were rated as grade I, and 8 cases as grade II. Conclusions MIS-TLIF by unilateral incision and internal fixation is a safe and reliable method to treat dural-level lumbar degenerative disease, and it has the advantages of short operation time, less invasion, less blood loss, and fast recovery.
Objective To analyze the medium and long-term effectiveness of microendoscope-assisted minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for lumbar degenerative diseases in comparison with conventional tubular retractor-assisted MIS-TLIF. Methods Between November 2008 and March 2013, 53 patients with single segment lumbar degenerative diseases were enrolled. According to the different working channel performed, 28 patients were treated by microendoscope-assisted MIS-TLIF (observation group), while the remaining cases received conventional tubular retractor-assisted MIS-TLIF via Wiltse approach (control group). Preoperative baseline data, including age, gender, body mass index, disease etiology, operated level, the ration for requiring bilateral canal decompression, and preoperative visual analogue scale (VAS) socre of low back pain and leg pain, Japanese Orthopedic Association (JOA) score, Oswestry disability index (ODI) score, showed no significant difference between the two groups (P>0.05). The operation time, intraoperative blood loss, intraoperative fluoroscopy time, postoperative analgesic drug dose, postoperation in-bed time, and perioperative complication incidence were recorded respectively and compared between the two groups. Radiographic evaluation of interbody fusion was performed based on Bridwell grading system at 2 years after operation. VAS scores of low back pain and leg pain, JOA score, and ODI score were assessed before operation, at 2 years after operation, and at last follow-up respectively. Surgical outcome satisfaction was assessed by modified MacNab criteria at last follow-up. Results When compared with those in control group, both intraoperative blood loss and postoperative analgesic drug dose were significantly decreased in observation group (P<0.05); similarly, the operation time and intraoperative fluoroscopy time were also significantly increased in observation group (P<0.05). There was no significant difference of postoperative in-bed time between the two groups (t=–0.812, P=0.420). Both groups were followed up 6-10.3 years, with an average of 7.9 years. Regarding perioperative complication, its incidence was 14.3% and 20.0% in observation group and control group, respectively, showing no significant difference between both groups (χ2=0.306, P=0.580). Specifically, there were intraspinal hematoma formation in 1 case, incision infection in 1 case, urinary infection in 1 case, transient delirium in 1 case in observation group. By contrast, there were dural tear and cerebrospinal fluid leakage in 1 case, urinary infection in 1 case, pneumonia in 1 case, transient delirium in 2 cases in control group. Bridwell criterion was used to judge the intervertebral fusion at 2 years after operation, the fusion rates of observation group and control group were 92.9% and 92.0%, respectively, showing no significant difference (χ2=0.162, P=0.687). At both 2-year postoperatively and last follow-up, the VAS scores of low back pain and leg pain, JOA score, and ODI score were significantly improved when compared with those before operation (P<0.01), whereas no significant difference between the two groups at either time point was found (P>0.05). At last follow-up, the results of patients’ satisfaction with surgery evaluated by modified MacNab criteria, and the excellent and good rates of the observation group and the control group were 96.4% and 92.0%, respectively, showing no significant difference (χ2=0.485, P=0.486). Conclusion The medium and long-term effectiveness of microendoscope-assisted MIS-TLIF are similar to those of conventional tubular retractor-assisted MIS-TLIF for lumbar degenerative diseases. The former operation has the additional advantages in terms of more clear surgical site visually, less intraoperative blood loss, and reduced postoperative analgesic dose, all of which seem more feasible to clinical teaching.
ObjectiveTo investigate the effectiveness of modified direction-changeable lumbar Cage in transforaminal lumbar interbody fusion (TLIF).MethodsA retrospective analysis was made of 161 patients with single segment L4 or L5 isthmic spondylolisthesis treated between January 2013 and December 2015. According to the implantation of Cage, they were divided into trial group (85 cases, modified direction-changeable lumbar Cage implanted in TLIF) and control group (76 cases, traditional nondirection-changeable Cage implanted in TLIF). There was no significant difference in the general data of gender, age, disease duration, slippage segment, and slippage grade between the two groups (P>0.05). The intraoperative implantation time of Cage, Cage position adjustments times, fluoroscopy times during implantation of Cage, fluoroscopy exposure time, and total operation time were recorded and compared between the two groups. Visual analogue scale (VAS) and Oswestry disability index (ODI) scores were used to evaluate the effectiveness of the patients before operation, and at 3, 6, and 12 months after operation, and the incidence of complications was recorded and analyzed. CT examinations were performed at 6 and 12 months after operation, and lumbar fusion was evaluated by Bridwell criteria.ResultsThe intraoperative implantation time of Cage, Cage position adjustments times, fluoroscopy times during implantation of Cage, fluoroscopy exposure time, and total operation time in trial group were significant less than those in control group (P<0.05). All the 161 patients were followed up 12-18 months (mean, 14.3 months). There was 1 case of dural sac tear in the trial group and 1 case of superficial infection in the control group; no complication such as dural tear and infection occurred in other patients. The fusion rate was 76.5% (64/85) in the trial group and 57.9% (44/76) in the control group at 6 months after operation, showing significant difference (χ2=6.44, P=0.02); at 12 months after operation, the fusion rate was 96.5% (82/85) in the trial group and 90.8% (69/76) in the control group (including 3 cases of Cage displacement and 4 cases of screw breakage), showing no significant difference in the fusion rate between the two groups (χ2=1.54, P=0.26). The VAS and ODI scores of the two groups decreased gradually at 3, 6, and 12 months after operation, and improved significantly when compared with those before operation (P<0.05). There was no significant difference in VAS and ODI scores between the two groups before and after operation (P>0.05).ConclusionBoth Cages can obtain the similar effectiveness. The modified direction-changeable lumbar Cage can significantly reduce the fluoroscopy times and radiation dose during TLIF, shorten the operation time, and effectively reduce the radiation exposure of patients and medical staff.
ObjectiveTo compare the effectiveness of robot-assisted minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and open freehand TLIF for the treatment of single-level degenerative lumbar spondylolisthesis (DSL) and analyse the influence on postoperative adjacent segmental degeneration (ASD). Methods The clinical data of 116 patients with L4、5 DLS who were admitted between November 2019 and October 2021 and met the selection criteria were retrospectively analyzed. According to the surgical methods, they were divided into the robotic group (45 cases, who underwent robot-assisted MIS-TLIF) and the open group (71 cases, who underwent open freehand TLIF). There was no significant difference in baseline data such as gender, age, body mass index, DLS Meyerding grading, and preoperative Pfirrmann grading, Weishaupt grading, L3, 4 intervertebral disc height (DH), L3, 4 intervertebral mobility, sagittal parameters [including pelvic incidence (PI), lumbar lordosis (LL), sacral slope (SS), pelvic tilt (PT)], and Cage height (P>0.05). The grade of facet joint violation (FJV) by pedicle screws on the superior articular process was assessed postoperatively. Sagittal parameters, L3, 4 DH, L3, 4 DH loss, and L3, 4 intervertebral mobility were measured preoperatively and at last follow-up in order to determine whether ASD occurred. Based on the occurrence of postoperative ASD, logistic regression analysis was used to identify the risk factors for ASD after TLIF. Results Patients in both groups were followed up 21-47 months, with a mean of 36.1 months; there was no significant difference in the follow-up time between the two groups (P>0.05). The occurrence of postoperative FJV was significantly better in the robotic group than in the open group (P<0.05). At last follow-up, the difference in the change values of sagittal parameters PI, PT, SS, and LL was not significant when comparing the two groups of patients (P>0.05); the change values of L3, 4 DH and L3, 4 DH loss in the robotic group were smaller than those in the open group, and the change value of L3, 4 intervertebral mobility was larger than that in the open group, and the differences were significant (P<0.05). At last follow-up, ASD occurred in 8 patients (17.8%) in the robotic group and 35 patients (49.3%) in the open group, and the difference in ASD incidence between the two groups was significant (P<0.05). logistic regression analysis showed that open surgery, preoperative Pfirrmann grading Ⅳ-Ⅴ, preoperative Weishaupt grading ≥2, and postoperative FJV grading ≥1 were risk factors for the development of ASD after TLIF (P<0.05). ConclusionCompared with traditional open surgery, orthopedic robot-assisted MIS-TLIF in the treatment of single-level DLS can more accurately insert pedicle screws, reduce the loss of DH and the occurrence of FJV, and effectively reduce the incidence of mid-postoperative ASD. Preoperative disc and synovial joint degeneration in adjacent segments, nonrobotic-assisted minimally invasive therapy, and FJV are risk factors for ASD after TLIF.
Based on the surgical model using transforaminal lumbar interbody fusion (TLIF) to treat lumbar spondylolisthesis, this paper presents the investigations of the biomechanical characteristics of cage and pedicle screw in lumbar spinal fusion implant fixed system under different combinations with finite element method. Firstly, combining the CT images with finite element pretreatment software, we established three dimensional nonlinear finite element model of human lumbar L4-L5 segmental slight slippage and implant under different fixed combinations. We then made a comparison analysis between the biomechanical characteristics of lumbar motion range, stress distribution of cage and pedicle screw under six status of each model which were flexion, extension, left lateral bending, right lateral bending, left axial rotation and right axial rotation. The results showed that the motion ranges of this model under different operations were reduced above 84% compared with those of the intact model, and the stability of the former was improved significantly. The stress values of cage and pedicle screw were relatively larger when they were fixed by single fusion device additional unilateral pedicle screw, but there was no statistically significant difference. The above research results would provide reference and confirmation for further biomechanics research of TLIF extracorporal specimens, and finally provide biomechanical basis for the feasibility of unilateral internal fixed diagonal intervertebral fusion TLIF surgery.
Objective To compare the effectiveness of percutaneous endoscopic transforaminal lumbar interbody fusion (PE-TLIF) and Wiltse-approach TLIF (W-TLIF) in the treatment of lumbar spondylolisthesis. MethodsThe clinical data of 47 patients with lumbar spondylolisthesis who met the selection criteria between July 2018 and June 2019 were retrospectively analyzed, in which 21 patients were treated with PE-TLIF (PE-TLIF group) and 26 patients were treated with W-TLIF (W-TLIF group). There was no significant difference between the two groups in age, gender, disease duration, level of spondylolisthesis vertebrae, spondylolisthesis degree, spondylolisthesis type, and preoperative visual analogue scale (VAS) score of low back pain and leg pain, lumbar Japanese Orthopaedic Association (JOA) score, and the disc height (DH), segmental lordosis (SL), and Taillard index (TI) of the operated vertebrae (P>0.05). The operation time, intraoperative blood loss, postoperative drainage, postoperative bedridden time, and complications were compared between the two groups. The VAS score and JOA score were used to evaluate the improvement of pain and function. At last follow-up, DH, SL, and TI of operated vertebrae were measured by X-ray films, and lumbar CT was performed to evaluate the interbody fusion. Results Compared with W-TLIF group, the operation time in PE-TLIF group was significantly longer, but the intraoperative blood loss and postoperative drainage were significantly less, and the postoperative bedridden time was significantly shorter (P<0.05). There were 2 cases of transient lower limb radiating pain in PE-TLIF group and 1 case of superficial incision infection in W-TLIF group. There was no significant difference in the incidence of complications (9.5% vs. 3.8%) between the two groups (χ2=0.037, P=0.848). The patients in both groups were followed up 12-24 months, with an average of 17.3 months in PE-TLIF group and 17.7 months in W-TLIF group. The VAS scores of low back pain and leg pain, and the JOA scores of the two groups significantly improved at each time point after operation when compared with those before operation (P<0.05). Compared with W-TLIF group, the VAS scores of low back pain in PE-TLIF group significantly lower at 3 days and 3 months after operation (P<0.05), and the JOA score of PE-TLIF group was significantly higher at 3 months after operation (P<0.05), and there was no significant difference in each score at any other time point between the two groups (P>0.05). At last follow-up, the DH, SL, and TI of operated vertebrae of the two groups significantly improved when compared with those before operation (P<0.05), and there was no significant difference in the differences of each parameter between the two groups (P>0.05). According to Suk’s standard, the fusion rates of PE-TLIF group and W-TLIF group were 90.5% (19/21) and 92.3% (24/26), respectively, with no significant difference (χ2=0.000, P=1.000). At last follow-up, there was no case of Cage sunk into the adjacent vertebral body, or dislodgement of Cage anteriorly or posteriorly in both groups. Conclusion PE-TLIF and W-TLIF are both effective in the treatment of grade Ⅰ and Ⅱ lumbar spondylolisthesis. Although the operation time is prolonged, PE-TLIF has less intraoperative blood loss and postoperative drainage, shorter postoperative bedridden time, and can get more obvious short-term improvement of low back pain and function.