Feasibility of enlarging the ventral space by using a drill under spinal endoscopy in the treatment of severe free lumbar disc herniation / 中国骨伤

OBJECTIVE@#To evaluate the clinical efficacy of spinal endoscopy in the treatment of severe free lumbar disc herniation and explore the feasibility and application of microscopic drills to expand ventral space.@*METHODS@#Thirty patients with severe free lumbar intervertebral disc herniation treated by spinal endoscopic technique from April 2019 to March 2021 were collected, including 19 males and 11 females;aged from 19 to 76 years with an average of (44.03±16.92) years old. All patients had a single segmental lesion with prolapse of the nucleus pulposus. Among them, there were 3 cases on L2,3, 3 cases on L3,4, 15 cases on L4,5, and 9 cases on L5S1. During operation, posterior bone of vertebral body and pedicle notch were removed by a drill under the endoscope to enlarge the ventral space. And the free nucleus pulposus was exposed and completely removed. The intraoperative blood loss, operation time, hospital stay and postoperative neurological complications were recorded, and Japanese Orthopaedic Association (JOA) score, Oswestry Disability Index (ODI) and visual analogue scale (VAS) were compared before operation, 2 days, 3 months and 1 year after operation, and Macnab standard was used to evaluate clinical efficacy.@*RESULTS@#All operations were successful and the free nucleus pulposus was completely removed. Pain in the lower back and legs was significantly relieved on the day after operation. Two patients experienced transient pain and numbness in lower limbs after operation, and no serious nerve injury complications occurred. ODI and VAS at each time point after surgery were significantly lower than those before surgery (P<0.01), and JOA score was significantly higher than before surgery (P<0.01). The excellent and good rates of Macnab were 66.67% (20/30), 83.33% (25/30) and 90.00% (27/30) on 2 days, 3 months and 1 year after operation, respectively.@*CONCLUSION@#For severe free lumbar intervertebral disc herniation, using of a drill under endoscope to expand the ventral space can smoothly remove the free nucleus pulposus and avoid nerve damage.

Analysis on clinical effects of two surgical approaches in percutaneous spinal endoscopy for LS disc herniation / 中国骨伤

OBJECTIVE@#To analyze the clinical effects, complications and operational key points of the percutaneous endoscopic transforaminal discectomy (PETD) and percutaneous endoscopic interlaminar discectomy (PEID) in treating LS disc herniation.@*METHODS@#The clinical data of 158 patients with L5S1 disc herniation treated from July 2015 to March 2018 were restospectively analyzed. According to different surgical approaches, the patients were divided into PETD group or PEID group, 79 cases in each group. In PETD group, there were 41 males and 38 females, with an average age of (41.38±6.25) years and course of disease of (10.06±3.14) months. In PEID group, there were 43 males and 36 females, with an average age of (41.18±5.78) years and course of disease of (9.99±2.83) months. The operation length, intraoperative blood loss, intraoperative fluoroscopy times, days of hospital stay, and complications were recorded between two groups. Visual analogue score (VAS), Japanese Orthopedic Association(JOA) score, Oswestry Disability Index(ODI), modified Macnab criteria were used to assessed clinical effects after operation.@*RESULTS@#All patients completed surgery and were followed up for more than 1 year. (1) There were no significant differences in the intraoperative blood loss or hospitalization length between two groups(>0.05). The operation length and intraoperative fluoroscopy times in PETD group were significantly higher than in PEID group (0.05). (3)The excellence rate was 89.87% (71 / 79) in PETD group and 87.34% (69 / 79) in PEID group at the latest follow-up, with no statistical significance(>0.05). (4)Complications occurred in 2 cases in PETD group and in 3 cases in PEID group, with no significant differences between two groups.@*CONCLUSION@#The short term efficacy of the PETD is equal to that of the PEID for the LS disc herniation, but PEID is superior in the operation length, the access of stereotaxic puncture and intraoperative fluoroscopy times. The complications can be effectively reduced by following the indications, mastering the endoscopic technique, operating carefully and being familiar with the key points of common complications.

Quantitative study on cytotoxicity of methylene blue to human nucleus pulposus cells by cell counting-kit 8 assay / 中国组织工程研究

BACKGROUND: Our preliminary study has shown that methylene blue exerts toxic effect on human nucleus pulposus cells in a concentration-dependent manner, but the toxic range remains unclear. OBJECTIVE: To determine the critical range of the cytotoxicity of methylene blue to nucleus pulposus cells by cell counting-kit 8 (CCK-8) assay. METHODS: The nucleus pulposus was from a patient with intervertebral disc herniation. The nucleus pulposus cells were extracted and cultured. Passage 1 cells mere used to make cell suspensions. The cells were divided into nine groups for culture: blank control (only the medium, CCK-8 solution), control (only medium, cells and CCK-8 solution), and methylene blue groups (1%, 0.5%, 0.1%, 0.05%, 0.01% and 0.005% of methylene blue). The absorbance values were measured by CCK-8 assay at 24, 48, 72 and 96 hours after incubation. The cell viability was calculated, and the color was observed. RESULTS AND CONCLUSION: The color in the control group was the darkest, and the color in the methylene blue groups became lighter with the concentration of methylene blue increasing, and the 0.05%, 0.01%, 0.005% and 0.001% methylene blue groups showed darker color similar to the control group. The absorbance values in the 0.1% methylene blue group were significantly less than those in the control group (P＜ 0.05). There were no significant differences in the absorbance values and cell viability between 1% and 0.5% methylene blue groups (P ＞0.05). The absorbance values and cell viability in the 0.1% methylene blue group were significantly higher than those in the 0.5% methylene blue group, but were significantly less than those in the 0.05% methylene blue group (P ＜ 0.05). Thus, methylene blue exerts cytotoxicity to human nucleus pulposus cells, and the critical value of toxicity is between 0.1% and 0.05% and close to 0.05%. However, the exact value needs a further investigation.

Toxicity of methylene blue to human nucleus pulposus cells detected by cell counting-kit 8 assay / 中国组织工程研究

BACKGROUND: Methylene blue is used as a developer to identify intervertebral disc degeneration in the transforaminal endoscopic surgery. However, many scholars have indicated that methylene blue can accelerate the degeneration process, whilst foreign researches have reported that it may play therapeutic effect on degenerative intervertebral discs under acidic conditions due to its acidophily. Therefore, whether methylene blue holds toxic effect on the disc remains controversial. OBJECTIVE: To determine whether methylene blue exerts toxic effect on nucleus pulposus cells by cell counting-kit 8 (CCK-8) assay. METHODS: The discarded nucleus pulposus from two patients with intervertebral disc herniation were selected. After digestion, nucleus pulposus cells were extracted and cultured until proliferated to 80% of the medium. Then, the cells were digested to make cell suspensions, divided into six groups and inoculated into the 96-well plates: blank control (only the medium, CCK-8 solution), control group (only medium, cells and CCK-8 solution), and the other groups were cultured with 1%, 2%, 3%, and 4% methylene blue, respectively. The absorbance values were measured by CCK-8 assay at 24, 48, 72 and 96 hours after incubation to calculate the cell viability, and the color change was observed. RESULTS AND CONCLUSION: The color in the control group was the deepest, and the color became lighter with the concentration of methylene blue increasing. The cell viability was the highest in the control group, and it was decreased with the concentration of methylene blue increasing. Thus, methylene blue may exert toxic effect on human nucleus pulposus cells.