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.
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 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.
Objective To investigate the short-term effectiveness of unilateral biportal endoscopic transforaminal lumbar interbody fusion (UBE-TLIF) in the treatment of Meyerding degree Ⅰ or Ⅱ single-segment lumbar spondylolisthesis. MethodsThe clinical data of 26 patients with Meyerding degree Ⅰ or Ⅱ single-segment lumbar spondylolisthesis treated with UBE-TLIF between January 2021 and August 2021 were retrospectively analyzed. Among them, there were 10 males and 16 females with a mean age of 61.5 years (range, 35-76 years). The lesion segment included L3, 4 in 2 cases, L4, 5 in 18 cases, and L5, S1 in 6 cases. There were 17 cases of degenerative spondylolisthesis and 9 cases of isthmic spondylolisthesis; according to the Meyerding classification of spondylolisthesis, 19 cases were grade Ⅰ and 7 cases were grade Ⅱ. Twenty-one cases were complicated with lumbar disc herniation and spinal stenosis and 5 cases with lumbar spinal stenosis. The operation time, hospitalization stay, complications, hemoglobin (Hb) and serum creatine kinase (CK) levels before operation and at 1 day after operation were recorded; lumbar lordosis angle changes and postoperative spondylolisthesis reduction were evaluated by lumbar anteroposterior and lateral X-ray films before operation and at last follow-up; visual analogue scale (VAS) score was used to evaluate the low back pain and leg pain before operation, at 2 days, 1 week, 2 weeks after operation, and at last follow-up; Oswestry disability index (ODI) was used to evaluate the functional recovery of the patients before operation and at last follow-up. ResultsThe operation was successfully completed in all 26 patients, with an average operation time of 181.9 minutes (range, 130-224 minutes) and an average hospitalization stay of 6.3 days (range, 3-9 days). Hb levels were significantly lower and serum CK levels were significantly higher at 1 day after operation when compared with those before operation (t=7.594, P<0.001; t=–15.647, P<0.001). No serious complication occurred during and after operation. CT examination at 3 days after operation showed that the percutaneous screw was not in good position in 1 case, and nerve paralysis (pain, numbness) occurred in 2 cases after operation, which were improved within 2 weeks after operation. All the 26 patients were followed up 6-11 months, with an average of 8.7 months. Complete reduction (the slippage reduction rate was 100%) was achieved in 24 patients (92.3%), and partial reduction (the slippage reduction rate was 87.5%) in 2 patients (7.7%). During the follow-up, there was no complication such as incision infection, fusion Cage subsidence or displacement, and internal fixator loosening. The VAS scores of low back pain and leg pain significantly improved at each time point after operation when compared with those before operation (P<0.05); there was no significant difference in the VAS scores of low back pain and leg pain between at 2 days and 1 week after operation, the VAS scores of low back pain between at 1 week and 2 weeks after operation, and the VAS scores of leg pain between at 2 weeks after operation and last follow-up (P>0.05); but there was significant difference between the other time points after operation (P<0.05). ODI and lumbar lordosis angle significantly improved at last follow-up (P<0.05). Conclusion UBE-TLIF provides favorable short-term effectiveness and obvious advantages of minimally invasive in the treatment of Meyerding degree Ⅰ or Ⅱ single-segment lumbar spondylolisthesis. However, the safety and long-term effectiveness need to be further studied.
ObjectiveTo explore the risk factors of coronal imbalance after posterior long-level fixation and fusion for degenerative lumbar scoliosis.MethodsRetrospectivly analyzed the clinical records of 41 patients with degenerative lumbar scoliosis who had received posterior long-level fixation and fusion with selective transforaminal lumbar interbody fusion (TLIF) accompanied by Ponte osteotomy between August 2011 and July 2016. Patients were divided into imbalance group (group A, 11 cases) and balance group (group B, 30 cases) according to state of coronal imbalance measured at last follow-up. The radiographic parameters at preoperation and last follow-up were measured, and the variance of preoperative and last follow-up parameters were calculated. The radiographic parameters included coronal Cobb angle, coronal balance distance (CBD), apical vertebral translation (AVT), apical vertebral rotation (AVR), Cobb angle of lumbar sacral curve (LSC), and L5 tilt angle (L5TA). Univariate analysis was performed for the factors including gender, age, preoperative T value of bone mineral density, number of instrumented vertebra, upper and lower instrumented vertebra, segments of TLIF, decompression, and Ponte osteotomy, as well as the continuous variables of preoperative imaging parameters with significant difference were converted into two-category variables, obtained the influence factors of postoperative coronal imbalance. Multivariate logistic regression analysis was performed to verify the risk factors from the preliminary screened influence factors and the variance of imaging parameters with significant difference between the two groups.ResultsThe follow-up time of groups A and B was (3.76±1.02) years and (3.56±1.03) years respectively, there was no significant difference between the two groups (t=0.547, P=0.587). The coronal Cobb angle, AVT, LSC Cobb angle, and L5TA in group A were significantly higher than those in group B before operation (P<0.05), and all the imaging parameters in group A were significantly higher than those in group B at last follow-up (P<0.05). There was no significant difference between the two groups in parameters including the variance of coronal Cobb angle, AVT, and LSC Cobb angle before and after operation (P>0.05), and there were significant differences between the two groups in parameters including the variance of CBD, L5TA, and AVR (P<0.05). Univariate analysis showed that preoperative L5TA was the influencing factor of postoperative coronal imbalance (P<0.05). Multivariate logistic regression analysis showed that preoperative L5TA≥15° was an independent risk factor of postoperative coronal imbalance, and variance of pre- and post-operative AVR was a protective factor.ConclusionPreoperative L5TA≥15° is an independent risk factor for coronal imbalance in patients with degenerative lumbar scoliosis after posterior long-level fixation and fusion.
ObjectiveTo explore the fusion effect of allograft Cages on transforaminal lumbar interbody fusion (TLIF).MethodsThe clinical data of 30 patients (38 vertebral segments) who underwent TLIF with allograft interbody fusion Cages between January 2015 and January 2017 were retrospectively analysed. There were 25 males and 5 females with an average age of 56.9 years (range, 44-72 years). The lesions included 20 cases of lumbar disc herniation, 7 cases of lumbar spondylolisthesis, and 3 cases of lumbar spinal stenosis. The operation section included 4 cases of L3, 4, 13 cases of L4, 5, 5 cases of L5, S1, 6 cases of L4, 5-L5, S1, and 2 cases of L3, 4-L4, 5. The disease duration was 6-36 months (mean, 12 months). The clinical effectiveness was evaluated by visual analogue scale (VAS) score, Oswestry disability index (ODI), and Japanese Orthopaedic Association (JOA) score at preoperation, 3 months and 6 months after operation, and last follow-up. The fusion rate was evaluated by anteroposterior and lateral X-ray films and CT three-dimensional reconstruction at 3 and 6 months after operation. The intervertebral space height was measured on anteroposterior and lateral X-ray films at preoperation, 3 days, 3 months, and 6 months after operation.ResultsThe operation time was 2.1-4.3 hours (mean, 3.1 hours), and the intraoperative blood loss was 150-820 mL (mean, 407.5 mL). The follow-up time was 8-25 months (mean, 16.4 months). One Cage split at 6 months after operation without Cage movement and neurologic symptoms; none of the other patients had Cage prolapse, displacement, and fragmentation. No local or systemic allergy or infection signs was found in all patients. No nerve compression or symptoms was observed during the follow-up. The postoperative VAS score, ODI score, and JOA score improved significantly when compared with preoperative scores (P<0.05); and the scores at 6 months and at last follow-up were significantly improved when compared with those at 3 months after operation (P<0.05); but no significant difference was found between at 6 months and at last follow-up (P>0.05). The fusion rate was 55.3% (21/38), 92.1% (35/38), and 100% (38/38) at 3 months, 6 months, and last follow-up postoperatively. The intervertebral space height was increased significantly at 3 days, 3 months, 6 months, and last follow-up postoperatively when compared with preoperative ones (P<0.05); and the loss of intervertebral space height was significant at last follow-up when compared with postoperative at 3 days (P<0.05).ConclusionThe allograft interbody fusion Cage contributes to the spine interbody fusion by providing an earlier stability and higher fusion rate.
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.
Objective To compare the effectiveness of unilateral biportal endoscopic transforaminal lumbar interbody fusion (UBE-TLIF) and endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) in the treatment of single-segment degenerative lumbar spinal stenosis with lumbar spondylolisthesis. Methods Between November 2019 and May 2023, a total of 81 patients with single-segment degenerative lumbar spinal stenosis with lumbar spondylolisthesis who met the selection criteria were enrolled. They were randomly divided into UBE-TLIF group (39 cases) and Endo-TLIF group (42 cases). There was no significant difference in baseline data between the two groups (P>0.05), including gender, age, body mass index, surgical segment, and preoperative visual analogue scale (VAS) scores for low back and leg pain, Oswestry Disability Index (ODI), and serum markers including creatine kinase (CK) and C reactive protein (CRP). Total blood loss (TBL), intraoperative blood loss, hidden blood loss (HBL), postoperative drainage volume, and operation time were recorded and compared between the two groups. Serum markers (CK, CRP) levels were compared between the two groups at 1 day before operation and 1, 3, and 5 days after operation. Furthermore, the VAS scores for low back and leg pain, and ODI at 1 day before operation and 1 day, 3 months, 6 months, and 12 months after operation, and intervertebral fusion rate at 12 months after operation were compared between the two groups. Results All surgeries were completed successfully without occurrence of incision infection, vascular or nerve injury, epidural hematoma, dural tear, or postoperative paraplegia. The operation time in UBE-TLIF group was significantly shorter than that in Endo-TLIF group, but the intraoperative blood loss, TBL, and HBL in UBE-TLIF group were significantly more than those in Endo-TLIF group (P<0.05). There was no significant difference in postoperative drainage volume between the two groups (P>0.05). The levels of CK at 1 day and 3 days after operation and CRP at 1, 3, and 5 days after operation in UBE-TLIF group were slightly higher than those in the Endo-TLIF group (P<0.05), while there was no significant difference in the levels of CK and CPR between the two groups at other time points (P>0.05). All patients were followed up 12 months. VAS score of low back and leg pain and ODI at each time point after operation significantly improved when compared with those before operation in the two groups (P<0.05); there was no significant difference in VAS score of low back and leg pain and ODI between the two groups at each time point after operation (P>0.05). There was no significant difference in the intervertebral fusion rate between the two groups at 12 months after operation (P>0.05). ConclusionUBE-TLIF and Endo-TLIF are both effective methods for treating degenerative lumbar spinal stenosis with lumbar spondylolisthesis. However, compared to Endo-TLIF, UBE-TLIF requires further improvement in minimally invasive techniques to reduce tissue trauma and blood loss.
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 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.
