BACKGROUND:The percutaneous pedicle screw technique effectively reduces the excessive injury of screw placement on paraspinal muscles, and promotes the recovery of the function of low back muscle after surgery. Minimal y invasive technique avoids some disadvantages such as large surgical trauma and more bleeding. Folding U-shaped hol ow pedicle screw has hol ow design and good distraction effect. After fixation, stress intensity, compression time, bending stiffness and torsional mechanical properties have been verified in the clinic. OBJECTIVE:To observe the clinical effect of folding U-shaped hol ow pedicle screw fixation combined with minimal access-posterior lumbar interbody fusion for single-level lumbar disc herniation. METHODS:Between January and December 2012, folding U-shaped hol ow pedicle screw fixation with minimal access-posterior lumbar interbody fusion was performed in 30 patients with lumbar disc herniation. The mean fol ow-up period was 12 months. Lumbago Visual Analog Scale, Oswestry Disability Index and imaging indicators were utilized to evaluate clinical therapeutic effects. RESULTS AND CONCLUSION:Preoperative Visual Analog Scale pain score and Oswestry Disability Index for al patients were 7.3±0.7 and 71.4±7.1, 2.9±0.7 and 29.8±3.6 at 3 days after surgery, showing significant differences. At 12 months, no significant difference in Visual Analog Scale pain score and Oswestry Disability Index was detected. Postoperative short-period fol ow-up demonstrated that al lumbar interbody fusion was achieved in one year. There was no complication such as implant failure or infection. These findings indicated that folding U-shaped hol ow pedicle screw fixation with minimal access-posterior lumbar interbody fusion for lumbar disc herniation showed good clinical therapeutic effects, high rate of interbody fusion and a low rate of complications and smal trauma.

BACKGROUND:The existing bone grafting apparatus are al long tubular-shape, antegrade bone grafting; however, the bone grains within the tube were difficult to put through, along with large bone loss. OBJECTIVE:To design a new concept of minimaly invasive bone grafting apparatus, so as to achieve the minimaly invasive bone grafting in vertebral body and intervertebral space. METHODS: On Solidworks 2012 software platform, the 3D three-dimensional solid modeling technology was employed to design a new concept of gun-shape bone grafting device with the characteristics of headend reversely placing at the grafting position and antegrade pushout, against the problems such as antegrade bone grafting, long bone grafting path and difficulty in bone grafting existing in precious percutaneous or/and transpedicular bone graft apparatus. The virtual assembly and simulative bone grafting surgery were performed with the bone grafting apparatus for observation of the instrument matching degree and grafting surgical procedures. RESULTS AND CONCLUSION: A set of minimaly invasive gun-shape bone grafting apparatus was successfuly designed; its length was 20 cm in total; the length of the front semi-closed bone tube was 2.5 cm. There are two kinds of diameter specifications: inner diameter of 3.5 mm/outer diameter of 4 mm, and inner diameter of 5 mm/outer diameter of 6 mm. Virtual assembly revealed that the grafting apparatus were wel matched. Stimulative surgery displayed that the bone grain loading and launch were simple. The gun-shape bone grafting device is reasonable in design, avoiding pushing too long distance, bone pushing difficulties, bone loss and other problems in previous tubular bone grafting apparatus. Percutaneous, endoscopic vertebrae or intervertebral space minimaly invasive bone grafting can be performed with this apparatus.

Objective To evaluate the accuracy and safety of pedicle-scope assisted pedicle screw fixation and percutaneous pedicle screw fixation for treating lumbar degenerative disease(LDD).Methods Thirty cases of LDD treated by mini-invasive transforaminal lumbar interbody fusion(TLIF) under microscope plus percutaneous pedicle screw fixation with fluoroscopy or pedicle-scope of lumbar spine from December 2013 to September 2015 were selected and divide into the percutaneous group and pediclescope group,15 cases in each group.The operative duration,intraoperative blood loss volume,hospital stay and complications were compared between the two groups.The clinical effects were assessed with visual analogue scale(VAS) and Oswestry disability index(ODI).The plain radiography,dynamic radiology and lumbar magnetic resonance imaging(MRI) and computed tomography (CT) were re-examined after operation for assessing the screw location and fusion rate.Results Eighty-four screws were placed in the percutaneous group and 70 screws in the pedicle-scope group.In the percutaneous group and pedicle-scope group,the mean intraoperative blood loss volume,mean operative duration,average times of C-arm fluoroscopy,mean length of hospital stay,mean time of off-bed and complication occurrence rate were measured,and the differences were not statistically significant (P＞ 0.05).In 6-month follow up,the VAS score and ODI score in the two groups were significantly improved compared with before operation(P＜0.01);the VAS score and ODI score were(2.50 ± 1.30) and (50.00-±-3.50) in pediclescope group,(3.00± 1.50) and (58.00 ±4.50) in percutaneous group,respectivehy,and the differences were statistically significant(P＜0.05);the improvement rates of clinical symptoms in the percutaneous group and pedicle-scope group were 73.33 ％ and 80.00 ％ respectively.The imaging reexamination showed that the placed screw location was good and lesion segment fusion was good without screw loosening.The location of 3 screws in the percutaneous group was deviated and adjusted by the second operation.Conclusion The accuracy and safety of pedicle-scope assisted screw placing for treating LDD are higher than those of conventional percutaneous pedicle screw fixation,moreover the operative time is shorter with less intraoperative bleeding.

BACKGROUND: There is no report on the treatment of suppurative discitis with posterior microendoscopic discectomy, antibiotic artificial bone implantation and one-stage percutaneous pedicle screw fixation. OBJECTIVE: To evaluate the clinical effectiveness of posterior microendoscopic debridement, antibiotic artificial bone implantation and one-stage percutaneous pedicle screw fixation for pyogenic spondylodiscitis. METHODS: Thirty-one patients with suppurative discitis admitted at the Department of Spinal Surgery, the First Affiliated Hospital of Guangzhou Medical University from January 2014 to December 2017, including 17 males and 14 females, aged 28-78 years, were included. All the patients underwent posterior microendoscopic lesion clearance and antibiotic artificial bone grafting and one-stage percutaneous pedicle screw fixation. The erythrocyte sedimentation rate and C-reactive protein levels were detected at postoperative follow-up. The Visual Analog Scale and the Japanese Orthopaedic Association scores were used for detection. RESULTS AND CONCLUSION: (1) All the surgical operations of the 31 patients were successfully completed and all patients had immediate relief of low back pain and lower extremity radiation pain. They were able to move ground wearing a waistband at 1-4 days postoperatively. (2) Thirty-one patients were followed up for 9-18 months. All patients had a significant decrease in C-reactive protein and erythrocyte sedimentation rate at 1 week after surgery, and C-reactive protein and erythrocyte sedimentation rate were in the normal range at 1, 3, and 6 months postoperatively. (3) The Visual Analog Scale scores of all patients at 1 week of follow-up were significantly lower than those before surgery (P < 0.05) , and the Japanese Orthopaedic Association scores were significantly higher than those before surgery (P < 0.05) . (4) In the follow-up examination of CT and MRI, there was no recurrence, pseudoarticular formation or internal fixation loosening. (5) These results suggest that posterior microendoscopic discectomy, antibiotic artificial bone implantation combined with one-stage percutaneous pedicle screw fixation for treating suppurative discitis can result in little trauma, few bleeding and rapid pain relief, and patients can move to the ground early. The operation method has a good clinical effect.