【Abstract】 Objective To investigate the effectiveness of surgical treatment for discogenic low back pain (DLBP) by minimally invasive transforaminal lumbar interbody fusion (TLIF) combined with unilateral pedicle screw fixation (UPSF). Methods Between March 2006 and July 2009, 57 patients with single-level DLBP were treated by minimally invasive TLIF combined with UPSF, including 27 males and 30 females with an average age of 45.6 years (range, 38-61 years) and a disease duration of 3.8 years (range, 9 months to 11 years). The involved segments included L2，3 in 2 cases, L3，4 in 5 cases, L4，5 in 29 cases, and L5, S1 in 21 cases. The operative time, incision length, intraoperative blood loss, postoperative drainage volume, hospitalization times, fusion rate, and complications were observed. The effectiveness were evaluated through Oswestry disability index (ODI) and visual analogue score (VAS), and the operative outcomes were compared in different groups classified according to various pressures of the contrast medium and sensitivities to discoblock after inducing consistent pain. Results The operation time, incision length, blood loss, postoperative drainage volume, and hospitalization times were (84.6 ± 37.4) minutes, (3.4 ± 0.6) cm, (132.5 ± 23.2) mL, (58.7 ± 21.4) mL, and (6.5 ± 0.8) days, respectively. All patients were followed up 2 years and 2 months to 5 years and 4 months (mean, 3.2 years). At last follow-up, ODI and VAS scores were significantly improved when compared with preoperative scores (P lt; 0.05). The effectiveness according to ODI were excellent in 27 cases, good in 22 cases, fair in 6 cases, and poor in 2 cases, with an excellent and good rate of 86.0%. All patients acquired b interbody fusion. At last follow-up according to ODI and VAS scores, better results were found in patients of low-pressure sensitive group and high-sensitive discoblock group (P lt; 0.05). Conclusion Minimally invasive TLIF combined with UPSF is reliable for DLBP with minimal surgical trauma, less paravertebral tissue injury, and fewer complications, but the indications for operation must be strictly followed. Patients being sensitive to low-pressure or high-sensitive to discoblock can achieve better surgical results.
To analyze the effectiveness of posterior pedicle screw system combined with interbodyfusion in treating lumbar spondylol isthesis. Methods Between January 2005 and January 2009, 26 patients with lumbar spondylol isthesis underwent posterior pedicle screw system combined with interbody fusion, including 11 males and 15 females with an average age of 56.8 years (range, 36-73 years). The disease duration was 7 months to 11 years. The affected lumbars were L3 in 3 cases, L4 in 12 cases, and L5 in 11 cases. According to the Meyerding evaluating system, 21 cases were classified as degree III, 5 cases as degree III-IV, and 1 case as degree IV. The cl inical results were investigated by measuring radiographic measurements, including Taillard index, Boxall index, sl i pping angle, lumbar lordosis angle,and intervertebral height index preoperatively, immediately, 2 weeks and 3 months postoperatively, respectively. SUK’s criteria was used to judge bone graft fusion. Results Primary heal ing of the incisions was achieved in all cases. Allpatients were followed up 25.8 months on average (range, 10-51 months). There were significant differences in Taillardindex, Boxall index, sl i pping angle, lumbar lordosis angle, and intervertebral height index between preoperatively andimmediately, 2 weeks, 3 months after operation (P lt; 0.05). Bone graft fusion was achieved at 3-8 months after operation(mean, 3.5 months); and the fusion rate was 100%. According to Japanese Orthopedic Association (JOA) scoring, theresults were excellent in 17 cases, good in 7 cases, fair in 1 case, and poor in 1 case; and the excellent and good rate was 92.3%. Compl ications occurred in 2 cases, including nail or rod breakage and nerve injury, and they were cured aftertreatment. Conclusion Posterior pedicle screw system combined with interbody fusion treating lumbar vertebralspondylol isthesis can afford sol id internal fixation and achieve a satisfactory reduction, so it maybe an ideal procedure and a worthy recommended method for treating lumbar spondylol isthesis.
Objective To compare the effectiveness of unilateral biportal endoscopy (UBE) technique assisted spinal canal decompression combined with percutaneous pedicle screw internal fixation versus traditional open decompression and internal fixation for treatment of lumbar burst fractures. MethodsA retrospective study was conducted on the clinical data of 61 patients with single-segment lumbar burst fractures who met the selection criteria and were admitted between October 2022 and December 2023. Of them, 25 patients received UBE technique assisted decompression combined with percutaneous pedicle screw fixation (UBE group), while 36 patients were treated with traditional posterior unilateral hemilaminectomy decompression and internal fixation (open group). There was no significant difference in baseline data between the two groups (P>0.05), including gender, age, body mass index, fracture segment, cause of injury, AO classification of lumbar fractures, and preoperative height ratio of the anterior margin of injured vertebra, segmental kyphosis angle, rate of spinal canal invasion, the classification of American Spinal Injury Association (ASIA) grading, visual analogue scale (VAS) score, and Oswestry disability index (ODI). The operation time, intraoperative blood loss, and postoperative complications were recorded and compared between the two groups. VAS score, ODI, and ASIA grading were used to evaluate the effectiveness before operation, at 1 week after operation, and at last follow-up. Lumbar anteroposterior and lateral X-ray films and CT were performed to measure the segmental kyphosis angle, height ratio of the anterior margin of injured vertebra, and the rate of spinal canal invasion.ResultsSurgery was successfully completed in both groups. No complication such as dural sac, nerve root, or vascular injury was found during operation, and all incisions healed by first intention. There was no significant difference in operation time between the two groups (P>0.05), the UBE group revealed significant less intraoperative blood loss when compared with open group (P<0.05). Patients in both groups were followed up 6-20 months, with an average of 13 months. There was no loosening, breakage, or failure of internal fixation in all patients. The ASIA grading, VAS score, ODI of the two groups significantly improved at 1 week after operation and further improved at last follow-up (P<0.05). There was no significant difference in ASIA grading at 1 week after operation and last follow-up between the two groups (P>0.05), but the VAS score and ODI in the UBE group were significantly superior to the open group (P<0.05). At 1 week after operation, the height ratio of the anterior margin of injured vertebra, segmental kyphosis angle, rate of spinal canal invasion significantly improved when compared to preoperative ones (P<0.05), the height ratio of the anterior margin of injured vertebra and segmental kyphosis angle significantly decreased at last follow-up when compared to the values at 1 week after operation (P<0.05), but the rate of spinal canal invasion was further significantly improved, and there was no significant difference between the two groups at different time point postoperatively. ConclusionUBE technique assisted spinal canal decompression combined with percutaneous pedicle screw fixation is a safe and effective treatment for lumbar burst fractures, which with little trauma and faster recovery when compared with traditional open decompression and internal fixation.
Objective To analyze the therapeutic effect of the posterior pedicle screw system combined with interbody fusion cage on lumbarspondylolisthesis. Methods From February 2003 to March 2006, 37 lumbar spondylolisthesis patients were treated with this operation, including21 males and 16 females and aging 3969 years.The affected lumbars were L3(3cases)，L4(23 cases), and L5(11 cases). According to the Meyerdingevaluating system, 12 cases were lassified as degree Ⅰ, 20 cases as degree Ⅱ,and 5 cases as degree Ⅲ. Taillard index, Boxall index, slipping angle, lumbar lordosis angle and intervertebral height index were measured before operation, and 2 weeks and 3 months after operation. Results All patients were followed up 336 months. There were statistically significant differences in Taillard index, Boxall index, slipping angle, lumbar lordosis angle and intervertebral height index between before operation and 2 weeks after operation (P＜0.05),and no statistically significant differences between 2 weeks and 3 months afteroperation(P＞0.05). According to Dewei Zhou’s creterior for scoring, the results were excellent in 27 cases， good in 8 cases，and fair in 2 cases. Theexcellent and good rate was 94.6%. All of the embedded osseous were fused. Thefusing time was from 3 to 8 months (mean 3-9 months). There were no breakageof screw and rod. The position and configuration of the whole cages were good. Conclusion Applying the posterior pedicle screw system combined with interbody fusion cage may achieve synergism in the treatment of lumbar vertebral spondylolisthesis. Above procedure is served as solid internal fixationand offers a satisfactory reduction, and can improve the fusion rate of the spine. So it is an ideal procedure and worthily recommended method for treatment oflumbar vertebral spondylolisthesis.
Objective To investigate the application value of intraoperative CT navigation in posterior thoracic pedicle screw placement for scoliosis patients. Methods Between October 2009 and December 2011, 46 patients with scoliosis were treated with thoracic pedicle screw placement under intraoperative CT navigation in 21 cases (group A) or under C-arm fluoroscopy in 25 cases (group B). There was no significant difference in age, gender, type of scoliosis, involved segment, and Cobb angle of main thoracic curve between 2 groups (P gt; 0.05). A total of 273 thoracic pedicle screws were placed in group A and 308 screws in group B. The pedicle screw position evaluated and classified by intraoperative CT images according to the Modi et al. method; and the accurate rate, the safe rate, and the potential risk rate of pedicle screws were calculated on the upper thoracic spine (T1-4), the middle thoracic spine (T5-8), the lower thoracic spine (T9-12), and the entire thoracic spine (T1-12). The accuracy and security of thoracic pedicle screw placement were compared between 2 groups. Results On the entire thoracic spine, the accurate rate of group A (93.4%) was significantly higher than that of group B (83.8%), the safe rate of group A (98.9%) was significantly higher than that of group B (92.5%), showing significant differences between 2 groups (P lt; 0.05). However, the potential risk rate of group B (7.5%) was significantly higher than that of group A (1.1%) (P lt; 0.05). On the upper, the middle, and the lower thoracic spines, there was no significant difference in the accurate rate, the safe rate, and the potential risk rate of pedicle screws between 2 groups (P gt; 0.05). According to CT evaluation results, the potential risk pedicle screws were revised or removed during operation. The patients of 2 groups had no neurological deficits through physical examination of nervous system at 3 days after operation. Conclusion Intraoperative CT navigation can improve the accuracy and security of posterior thoracic pedicle screw placement and it can ensure the safety of operation by finding and promptly removing or revising the potential risk pedicle screws.
Objective To explore the feasibility and accuracy of ultrasound volume navigation (UVN) combined with X-ray fluoroscopy-guided percutaneous pedicle screw implantation through a prospective randomized controlled study. Methods Patients with thoracic and lumbar vertebral fractures scheduled for percutaneous pedicle screw fixation between January 2022 and January 2023 were enrolled. Among them, 60 patients met the selection criteria and were included in the study. There were 28 males and 32 females, with an average age of 49.5 years (range, 29-60 years). The cause of injury included 20 cases of traffic accidents, 21 cases of falls, 17 cases of slips, and 2 cases of heavy object impact. The interval from injury to hospital admission ranged from 1 to 5 days (mean, 1.57 days). The fracture located at T12 in 15 cases, L1 in 20 cases, L2 in 19 cases, and L3 in 6 cases. The study used each patient as their own control, randomly guiding pedicle screw implantation using UVN combined with X-ray fluoroscopy on one side of the vertebral body and the adjacent segment (trial group), while the other side was implanted under X-ray fluoroscopy (control group). A total of 4 screws and 2 rods were implanted in each patient. The implantation time and fluoroscopy frequency during implantation of each screw, angle deviation and distance deviation between actual and preoperative planned trajectory by imaging examination, and the occurrence of zygapophysial joint invasion were recorded. Results In terms of screw implantation time, fluoroscopy frequency, angle deviation, distance deviation, and incidence of zygapophysial joint invasion, the trial group showed superior results compared to the control group, and the differences were significant (P<0.05). Conclusion UVN combined with X-ray fluoroscopy-guided percutaneous pedicle screw implantation can yreduce screw implantation time, adjust dynamically, reduce operational difficulty, and reduce radiation damage.
Objective To biomechanically compare the maximum pull-out strengths among two pedicle screws and three salvage techniques using poly methylmethacrylate (PMMA) augmentation in osteoporotic sacrum, and to determine which PMMA augmentation technique could serve as the salvage fixation for loosening sacral pedicle screws. Methods Eleven sacra were harvested from fresh adult donated cadavers, aged from 66 to 83 years (average 74.4 years) and included 5 men and 6 women. Radiography was used to exclude sacra that showed tumor or inflammatory or any other anatomic abnormal ities. Following the measurement of bone mineral density, five sacral screw fixations were sequentially establ ished on the same sacrum as follows: unicortical pedicle screw (group A), bicortical pedicle screw (group B), unicortical pedicle screw with the traditional PMMA augmentation (group C), ala screw with the traditional PMMA augmentation (group D), and ala screw with a kyphoplasty-assisted PMMA augmentation technique (group E). According to the sequence above, the axial pull-out test of each screw was conducted on a MTS-858 material testing machine. The maximum pull-out forces were measured and compared. The morphologies of PMMA augmented screws after being pulled-out were also inspected. Results The average bone mineral density of 11 osteoporotic specimens was (0.71 ± 0.08) g/cm2 . By observation of the pull-out screws, groups C, D, E showed perfect bonding with PMMA, and group E bonded more PMMA than groups C and D. The maximum pull-out forces of groups A, B, C, D, and E were (508 ± 128), (685 ± 126), (846 ± 230), (543 ± 121), and (702 ± 144) N, respectively. The maximum pull-out strength was significantly higher in groups B, C, and E than in groups A and D (P lt; 0.05), and in group C than in groups B and E (P lt; 0.05). There was no significant difference in pull-out strength between groups A and D, and between groups B and E (P gt; 0.05). Conclusion For sacral screw fixation of osteoporotic patients with bone mineral density more than 0.7 g/cm2, bicortical pedicle screw could acquire significantly higher fixation strength than the unicortical. Once the loosening of pedicle screw occurs, the traditional PMMA augmentation or ala screw with kyphoplasty-assisted PMMA augmentation may serve as a suitable salvage technique.
Objective To investigate the effectiveness of computer-assisted and robot-assisted atlantoaxial pedicle screw implantation for the treatment of reversible atlantoaxial dislocation (AAD). MethodsThe clinical data of 42 patients with reversible AAD admitted between January 2020 and June 2023 and met the selection criteria were retrospectively analyzed, of whom 23 patients were treated with computer-assisted surgery (computer group) and 19 patients were treated with Mazor X spinal robot-assisted surgery (robot group). There was no significant difference in gender, age, T value of bone mineral density, body mass index, etiology, and preoperative Japanese Orthopaedic Association (JOA) score, Neck Dysfunction Index (NDI) between the two groups (P>0.05). The operation time, screw implantation time, intraoperative blood loss, hand and wrist radiation exposure, and complications were recorded and compared between the two groups. Gertzbein classification was used to evaluate the accuracy of screw implantation. JOA score and NDI were used to evaluate the function before operation, at 3 days after operation, and at last follow-up. At last follow-up, the status of screws and bone fusion were observed by neck three-dimensional CT. Results The operation time and hand and wrist radiation exposure of the computer group were significantly longer than those of the robot group (P<0.05), and there was no significant difference in the screw implantation time and intraoperative blood loss between the two groups (P>0.05). All patients were followed up 11-24 months, with an average of 19.6 months. There was no significant difference in the follow-up time between the two groups (P>0.05). There was no significant difference in the accuracy of screw implantation between the two groups (P>0.05). Except for 1 case of incision infection in the computer group, which improved after antibiotic treatment, there was no complication such as nerve and vertebral artery injury, screw loosening, or breakage in the two groups. The JOA score and NDI significantly improved in both groups at 3 days after operation and at last follow-up (P<0.05) compared to those before operation, but there was no significant difference between the two groups (P>0.05). At last follow-up, 21 patients (91.3%) in the computer group and 18 patients (94.7%) in the robot group achieved satisfactory atlantoaxial fusion, and there was no significant difference in the fusion rate between the two groups (P>0.05). ConclusionComputer-assisted or robot-assisted atlantoaxial pedicle screw implantation is safe and effective, and robotic navigation shortens operation time and reduces radiation exposure.
ObjectiveTo evaluate the feasibility and safety of three-dimensional (3D) printed drill guide template-assisted percutaneous pedicle screw fixation for multiple-level thoracolumbar fractures.MethodsClinical data of 19 patients with multilevel thoracolumbar fracture without nerve injury who underwent surgical treatment between May 2017 and January 2019 were retrospectively analyzed. There were 9 males and 10 females and their age ranged from 22 to 63 years, with an average age of 43.6 years. Injury cause included traffic accident injury in 12 cases, and fall from height injury in 7 cases. A total of 40 fractured vertebrae were involved in T10 to L3 levels. According to AO classification, there were 29 fractures of type A1, 9 fractures of type A2, and 2 fractures of type A3. According to TANG Sanyuan classification, multiple-segment thoracolumbar fractures were classified as 17 cases of type ⅠA, 1 case of type ⅠB, and 1 case of type ⅡC. The time from injury to operation was 2-6 days, with an average of 3.1 days. The 3D-printed universal drill guide template was used for assisting percutaneous pedicle screw fixation during operation. Intraoperative blood loss, average operation time and fluoroscopy frequency of each screw were recorded. Visual analogue scale (VAS) score was used to evaluate the improvement of low back pain before operation, at 3 days after operation, and at last follow-up. According to the CT at 3 days after operation, the Gertzbein and Robbins scales were used to evaluate the accuracy of screw insertion (the grade A and grade B were regarded as accuracy, the grade A was regarded as excellent of screw insertion). The Cobb angle in sagittal plane of the fracture segment was measured, and the percentage of anterior edge of injured vertebral height was calculated. The consistency of the inclination of bilateral pedicle screws were analyzed postoperatively, and compared the angle of the intraoperative guide plate with the inclination of screw to verify the effectiveness of the guide plate in controlling the inclination.ResultsAll the 19 patients completed the operation successfully, and the intraoperative blood loss was 44-67 mL, with an average of 54.3 mL. The average operation time for each screw insertion was 7.3-11.1 minutes, with an average of 9.6 minutes. The average fluoroscopy frequency of each screw insertion was 1.6-2.5 times, with an average of 2.0 times. No spinal cord, nerve root injury, infection, and other complications occurred. All patients were followed up 24-38 months, with an average of 28.7 months. The accuracy of pedicle screws was evaluated by using Gertzbein and Robbins scales: 145 screws were grade A and 11 screws were grade B. The accuracy of screw insertion was 100% and the excellent rate was 92.9%. The CT data at 3 days after operation showed no significant difference in the inclination between the left and right screws in the same vertebral body (t=0.93, P=0.36). There was no significant difference between the angle of guide plate and the screw inclination (P>0.05). The VAS score, Cobb angle in sagittal plane, and the percentage of anterior edge of injured vertebral height were significantly improved at 3 days after operation and at last follow-up, and the VAS score was declined at last follow-up compared with 3 days after operation, all showing significant differences (P<0.05). There was no significant difference in the sagittal Cobb angle and the percentage of anterior edge of injured vertebral height between two postoperative time points (P>0.05). At last follow-up, no internal fixators were loosened or broken, and all fractures healed well.ConclusionFor the multiple-level thoracolumbar fractures, 3D-printed drill guide template assisting percutaneous pedicle screw fixation can reduce the operation time, intraoperative blood loss, and fluoroscopy frequency and the screw insertion is accurate and has a good reduction effect.
Objective To explore the clinical effect of PSIS-A robot-assisted percutaneous screw in the treatment of thoracolumbar fracture. Methods Patients with thoracolumbar fracture who were hospitalized in Mianyang Orthopedic Hospital between August 2022 and January 2024 and required percutaneous pedicle screw f ixation were selected. Patients were divided into robot group and free hand group by random number table. Operative time, intraoperative bleeding, intraoperative radiation dose and time, implant accuracy rate, small joint invasion rate, Visual Analogue Scale score for pain and other indexes were compared between the two groups. Results A total of 60 patients were included. Among them, there were 28 cases in the robot group and 32 cases in the free hand group. On the third day after surgery, the Visual Analogue Scale score of the robot group was better than that of the free hand group (P=0.003). Except for intraoperative bleeding and radiation frequency (P>0.05), the surgical time, average nail implantation time, and intraoperative radiation dose in the robot group were all lower than those in the free hand group (P<0.05). The accuracy and excellence rate of nail planting in the robot group were higher than those in the free hand group (94.6% vs. 84.9%; χ2=7.806, P=0.005). There was no statistically significant difference in the acceptable accuracy rate (96.4% vs. 91.1%; χ2=3.240, P=0.072) and the incidence of screw facet joint invasion (7.2% vs.14.1%; χ2=3.608, P=0.058) between the two groups. Conclusion The application of PSIS-A type robot assisted percutaneous minimally invasive pedicle screw fixation in the treatment of thoracolumbar fr actures is promising.