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.
Objective To compare the clinical and radiological outcomes of unilateral biportal endoscopic transforaminal lumbar interbody fusion (UBE-TLIF) and minimally invasive tubular TLIF (MT-TLIF) in treatment of lumbar degenerative diseases. Methods A clinical data of 75 patients with lumbar degenerative diseases, who met the selection criteria between August 2019 and August 2020, was retrospectively analyzed, including 35 patients in the UBE- TLIF group and 40 patients in the MT-TLIF group. There was no significant difference in general data such as gender, age, body mass index, disease type and duration, and surgical segment between the two groups (P>0.05), which was comparable. The operation time, intraoperative blood loss, hemoglobin (Hb) before operation and at 1 day after operation, the length of hospital stay, incidence of complications, and visual analogue scale (VAS) score of low back and leg pain, Oswestry Disability Index (ODI), Short-Form 36 Health Survey Scale (SF-36 scale), intervertebral disc height (IDH), sagittal Cobb angle, lumbar lordosis (LL), and the intervertebral fusion were compared between the two groups. Results Compared with MT-TLIF group, UBE-TLIF group had significantly longer operation time but less intraoperative blood loss and shorter length of hospital stay (P<0.05). The Hb levels in both groups decreased at 1 day after operation, but there was no significant difference in the difference before and after operation between the two groups (P>0.05). All patients were followed up, and the follow-up time was (14.7±2.5) months in the UBE-TLIF group and (15.0±3.4) months in the MT-TLIF group, with no significant difference (t=0.406, P=0.686). In both groups, the VAS score of low back pain, VAS score of leg pain, SF-36 scale, and ODI after operation significantly improved when compared with those before operation (P<0.05). There was no significant difference between 1 month after operation and last follow-up (P>0.05). There was no significant difference in the VAS score of low back pain, VAS score of leg pain, and SF-36 scale between the two groups before and after operation (P>0.05). At 1 month after operation, the ODI in the UBE-TLIF group was significantly better than that in the MT-TLIF group (P<0.05). At 1 month after operation, IDH, Cobb angle, and LL in both groups recovered when compared with those before operation (P<0.05), and were maintained until last follow-up (P>0.05). There was no significant difference in the IDH, Cobb angle, and LL between the two groups at each time point (P>0.05). Thirty-three cases (89.2%) in the UBE-TLIF group and 35 cases (87.5%) in the MT-TLIF group achieved fusion, and the difference was not significant (χ2=0.015, P=0.901). In the UBE-TLIF group, 1 case of intraoperative dural tear and 1 case of postoperative epidural hematoma occurred, with an incidence of 5.7%. In the MT-TLIF group, 1 case of intraoperative dural tear, 1 case of postoperative epidural hematoma, and 1 case of superficial infection of the surgical incision occurred, with an incidence of 7.5%. There was no significant difference in the incidence of complications between the two groups (χ2=1.234, P=1.000). Conclusion Compared with MT-TLIF, UBE-TILF can achieve similar interbody fusion in the treatment of lumbar degenerative diseases, and has the advantages of smaller incision, less bleeding, and shorter length of hospital stay.
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.
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 and imaging features between implanting single and double Cage into intervertebral body through unilateral transforaminal lumbar interbody fusion (TLIF). MethodsThe clinical data were collected and analyzed from 104 patients who underwent unilateral TLIF between January 2013 and October 2014, who were divided into 2 groups:single Cage was implanted into intervertebral body in 64 cases (76 segments) in traditional group, and double Cage was implanted into intervertebral body in 56 cases (70 segments) in reformative group. There was no significant difference in age, gender, bone mineral density, operation segments between 2 groups (P>0.05). The visual analogue scale (VAS), Oswestry disability index (ODI), and Japanese Orthopedic Association (JOA) scores were used to evaluate the effectiveness; the area of intervertebral bone-graft, fusion rate, height of intervertebral space, and the number of Cage subsidence were measured by CT scan. ResultsAll the patients were followed up 12.85 months on average (range, 9-15 months). The VAS, ODI, and JOA scores were significantly improved at each time point after operation when compared with preoperative values (P<0.05), and no significant difference was found between 2 groups (P>0.05) except VAS and ODI at 12 months after operation (P<0.05). However, the area of intervertebral bone-graft in reformative group[(5.94±1.17) cm2] was significantly larger than that in traditional group[(4.81±0.97) cm2] at 7 days after operation (t=-6.365, P=0.000). At 3 and 12 months after operation, the fusion rate was respectively 84.2% and 92.1% in traditional group and was respectively 88.6% and 94.3% in reformative group. Although the height of intervertebral space were increased when compared with preoperative height, the incidence rates of Cages subsidence in traditional group were 44.74% and 47.37% respectively at 3 and 12 months after operation and were significantly higher those that in reformative group (11.43% and 14.29% respectively) (P<0.05). In addition, the height difference between affected side and normal side in traditional group was significantly larger than that in reformative group (P<0.05). ConclusionBoth single and double Cage implanted into the intervertebral body through unilateral TLIF have good effectiveness. However, double Cage implanted into intervertebral body may hold the height of intervertebral space, reduce the incident rate of Cage subsidence, and prevent sagittal imbalance.
ObjectiveTo compare the effect of intravenous 20% mannitol or dexamethasone (DM) on low back and leg pain after minimally invasive transforaminal lumbar interbody fusion (MI-TLIF). MethodsBetween October 2012 and September 2013, 100 patients with degenerative lumbar diseases underwent MI-TLIF and percutaneous pedicle screw fixation. All patients were randomly divided into 3 groups:34 patients received intravenous 20% mannitol after operation (mannitol group); 32 patients received intravenous DM after operation (DM group); and 34 patients received neither dehydrating agent nor steroid after operation (control group). There was no significant difference in gender, age, disease duration, clinical symptoms, lesion types, and lesion segments between groups (P>0.05). The serum levels of inflammatory factors[tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and IL-6] were measured by ELISA at pre-operation and 3, 24, 48, 72, and 96 hours after operation. Low back and leg pain was determined by using visual analogue scale (VAS) score after operation. ResultsAll procedures were smoothly performed without major complications of nerve root injury, hematoma, or infection. There was no significant difference in operation time and intraoperative blood loss between groups (P>0.05). The VAS score of low back pain showed no significant difference between groups at all time points after operation (P>0.05); the VAS score of leg pain in the DM group was significantly lower than that in the control group at all time points (P<0.05), and than those in the mannitol group at 3, 24, 48, and 96 hours after operation (P<0.05). The serum level of TNF-α in the DM group was significantly lower than that in the control group at all time points (P<0.05), and than that in the mannitol group at 3, 48, 72, and 96 hours after operation (P<0.05). The serum level of IL-1β in the DM group was significantly lower than that in the control group at 3, 24, 48, and 72 hours after operation (P<0.05), and than that in the mannitol group at all time points after operation (P<0.05). The serum level of IL-6 in the DM group was significantly lower than that in the control group at 3 and 24 hours after operation (P<0.05), and than that in the mannitol group at 3, 24, and 48 hours after operation (P<0.05). ConclusionIntravenous 20% mannitol may has no effect on postoperative low back and leg pain, while DM can markedly relieve leg pain after MI-TLIF.
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.
ObjectiveTo explore the value of modified subcutaneous lumbar spine index (MSLSI) as a predictor for short-term effectiveness of transforaminal lumbar interbody fusion (TLIF) in treatment of lumbar degenerative disease (LDD).MethodsBetween February 2014 and October 2019, 450 patients who were diagnosed as LDD and received single-segment TLIF were included in the study. Based on the MSLSI measured by preoperative lumbar MRI, the patients were sorted from small to large and divided into three groups (n=150). The MSLSI of group A was 0.11-0.49, group B was 0.49-0.73, and group C was 0.73-1.88. There was no significance in gender, age, disease duration, diagnosis, surgical segment, and improved Charlson comorbidity index between groups (P>0.05). There were significant differences in the subcutaneous adipose depth of the L4 vertebral body and body mass index (BMI) between groups (P<0.05). The operation time, intra-operative blood loss, length of incision, drainage tube placement time, drainage volume on the 1st day after operation, drainage volume on the 2nd day after operation, total drainage volume, antibiotic use time after operation, walking exercise time after operation, hospital stay, the incidences of surgical or non-surgical complications in the three groups were compared. Pearson correlation analysis was used to analyze the correlation between MSLSI and BMI, and partial correlation analysis was used to study the relationship between MSLSI, BMI, improved Charlson comorbidity index, subcutaneous adipose depth of the L4 vertebral body and complications. The Receiver Operating Characteristic (ROC) curve was used to evaluate the value of SLSI and MSLSI in predicting the occurrence of complications after TLIF in treatment of LDD.ResultsThere was no significant difference in operation time, length of incision, antibiotic use time after operation, walking exercise time after operation, drainage tube placement time, drainage volume on the 1st day after operation, drainage volume on the 2nd day after operation, and total drainage volume between groups (P>0.05). The amount of intra-operative blood loss in group C was higher than that in groups A and B, and the hospital stay was longer than that in group B, with significant differences (P<0.05). Surgical complications occurred in 22 cases (14.7%), 25 cases (16.7%), and 39 cases (26.0%) of groups A, B, and C, respectively. There was no significant difference in the incidence between groups (χ2=0.826, P=0.662). The incidences of nerve root injury and wound aseptic complications in group C were higher than those in groups A and B, and the incidence of nerve root injury in group B was higher than that in group A, with significant differences (P<0.05). There were 13 cases (8.7%), 7 cases (4.7%), and 11 cases (7.3%) of non-surgical complications in groups A, B, and C, respectively, with no significant difference (χ2=2.128, P=0.345). There was no significant difference in the incidences of cardiovascular complications, urinary system complications, central system complications, and respiratory system complications between groups (P>0.05). There was a correlation between MSLSI and BMI in 450 patients (r=0.619, P=0.047). Partial correlation analysis showed that MSLSI was related to wound aseptic complications (r=0.172, P=0.032), but not related to other surgical and non-surgical complications (P>0.05). There was no correlation between BMI, improved Charlson comorbidity index, subcutaneous adipose depth of the L4 vertebral body and surgical and non-surgical complications (P>0.05). ROC curve analysis showed that the area under ROC curve (AUC) of MSLSI was 0.673 (95%CI 0.546-0.761, P=0.025), and the AUC of SLSI was 0.582 (95%CI 0.472-0.693, P=0.191). ConclusionMSLSI can predict the short-term effectiveness of TLIF in treatment of LDD. Patients with high MSLSI suffer more intra-operative blood loss, longer hospital stay, and higher incidence of nerve root injury and postoperative incision complications.
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.
ObjectiveTo compare the effectiveness of modified transforaminal lumbar interbody fusion (modified-TLIF) and posterior lumbar interbody fusion (PLIF) for mild to moderate lumbar spondylolisthesis in middle-aged and elderly patients.MethodsThe clinical data of 106 patients with mild to moderate lumbar spondylolisthesis (Meyerding classification≤Ⅱ degree) who met the selection criteria between January 2015 and January 2017 were retrospectively analysed. All patients were divided into modified-TLIF group (54 cases) and PLIF group (52 cases) according to the different surgical methods. There was no significant difference in preoperative clinical data of gender, age, disease duration, sliding vertebra, Meyerding grade, and slippage type between the two groups (P>0.05). The intraoperative blood loss, operation time, postoperative drainage volume, postoperative bed time, hospital stay, and complications of the two groups were recorded and compared. The improvement of pain and function were evaluated by the visual analogue scale (VAS) score and Japanese Orthopedic Association (JOA) score at preoperation, 1 week, and 1, 6, 12 months after operation, and last follow-up, respectively. The effect of slip correction was evaluated by slip angle and intervertebral altitude at preoperation and last follow-up, and the effectiveness of fusion was evaluated according to Suk criteria.ResultsAll patients were followed up, the modified-TLIF group was followed up 25-36 months (mean, 32.7 months), the PLIF group was followed up 24-38 months (mean, 33.3 months). The intraoperative blood loss, operation time, postoperative drainage volume, postoperative bed time, and hospital stay of the modified-TLIF group were significantly less than those of the PLIF group (P<0.05). The VAS score and JOA score of both groups were significantly improved at each time point after operation (P<0.05); the scores of the modified-TLIF group were significantly better than those of the PLIF group at 1 and 6 months after operation (P<0.05). The slip angle and intervertebral altitude of both groups were obviously improved at last follow-up (P<0.05), and there was no significant difference between the two groups at preoperation and last follow-up (P>0.05). At last follow-up, the fusion rate of the modified-TLIF group and the PLIF group was 96.3% (52/54) and 98.1% (51/52), respectively, and no significant difference was found between the two groups (χ2=0.000, P=1.000). About complications, there was no significant difference between the two groups in nerve injury on the opposite side within a week, incision infection, and pulmonary infection (P>0.05). No case of nerve injury on the operation side within a week or dural laceration occurred in the modified-TLIF group, while 8 cases (15.4%, P=0.002) and 4 cases (7.7%, P=0.054) occurred in the PLIF group respectively.ConclusionModified-TLIF and PLIF are effective in the treatment of mild to moderate lumbar spondylolisthesis in middle-aged and elderly patients. However, modified-TLIF has relatively less trauma, lower blood loss, lower drainage volume, lower incidence of dural laceration and nerve injury, which promotes enhanced recovery after surgery.