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Objective:To compare the clinical utility of 18F-fibroblast activating protein inhibitor (FAPI)-42 and 18F-fluorodeoxyglucose (FDG) PET/CT imaging in newly diagnosed lung cancer patients. Methods:From May 2020 to September 2021, the images of 43 lung cancer patients (32 males, 11 females, age: 37-80 years) who pathologically confirmed and received 18F-FDG and 18F-FAPI-42 PET/CT within 2 weeks in the First Affiliated Hospital of Guangzhou Medical University were prospectively analyzed. The maximum standardized uptake value (SUV max) of 18F-FDG and 18F-FAPI-42 and the number of lesions detected by 2 imaging methods were compared by using paired t test and Wilcoxon rank sum test. Results:The 43 newly diagnosed lung cancer patients included 35 adenocarcinoma, 2 squamous cell carcinoma, 4 small cell lung cancer, and 2 high-grade neuroendocrine tumors. 18F-FAPI-42 had a very high tumor uptake (SUV max: 12.24±3.97) and lesion detection rate (positive rate: 100%(37/37)) in primary lung adenocarcinoma and squamous cell carcinoma. The uptake of 18F-FAPI-42 in lymph node (10.13±5.43), pleura (6.75(4.96, 8.58)) and bone lesion (7.18(4.33, 9.66)) were significantly higher than those of 18F-FDG (6.35±3.30, 2.69(1.81, 5.00), 4.38(2.96, 6.36); t=12.19, z values: 5.47, 5.79, all P<0.001). In lung adenocarcinoma and squamous cell carcinoma, although the uptake of 18F-FAPI-42 in brain metastases was significantly lower than that of 18F-FDG (0.72(0.15, 1.82) vs 6.53(4.65, 9.34); z=6.42, P<0.001), the tumor/background (T/B) ratio was significantly higher than that of 18F-FDG (3.54(1.15, 14.88) vs 0.96(0.77, 1.04); z=6.05, P<0.001). In lung adenocarcinoma and squamous cell carcinoma, the number of lesions detected by 18F-FAPI-42 PET/CT was significantly more than that of 18F-FDG (lymph node: 6.0(2.3, 11.5) vs 4.5(2.0, 10.8); brain: 2.0(1.0, 3.0) vs 0.0(0.0, 0.0); pleura: 6.0(2.8, 10.0) vs 4.0(0.8, 5.5); z values: 2.16, 3.10, 2.04, all P<0.05). However, in high-grade neuroendocrine tumors and small cell lung cancer, the SUV max of 18F-FAPI-42 in primary lesions (8.05±2.60), lymph node lesions (5.98±2.21) and brain lesions (0.44(0.13, 0.82)) were lower than those of 18F-FDG (16.28±5.17, 12.30±5.47, 4.94(4.84, 6.25); t values: 3.58, 7.52, z=3.06, all P<0.05). Conclusions:In lung adenocarcinoma and squamous cell carcinoma, 18F-FAPI-42 has a very high tumor uptake and lesion detection rate in primary tumor. In addition, compared with 18F-FDG PET/CT, 18F-FAPI-42 PET/CT shows clearer tumor contours and more lesions. Therefore, 18F-FAPI-42 is more suitable for preliminary staging of lung adenocarcinoma and squamous cell carcinoma than 18F-FDG, while the opposite is true in small cell lung cancer and high-grade neuroendocrine tumors.
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Objective@#To analyze the correlations between intraoperative ultrasound and MRI metrics of the spinal cord in degenerative cervical myelopathy and identify novel potential predictive ultrasonic indicators of neurological recovery for degenerative cervical myelopathy. @*Materials and Methods@#Twenty-two patients who underwent French-door laminoplasty for multilevel degenerative cervical myelopathy were followed up for 12 months. The Japanese Orthopedic Association (JOA) scores were assessed preoperatively and 12 months postoperatively. Maximum spinal cord compression and compression rates were measured and calculated using both intraoperative ultrasound imaging and preoperative T2-weight (T2W) MRI. Signal change rates of the spinal cord on preoperative T2W MRI and gray value ratios of dorsal and ventral spinal cord hyperechogenicity on intraoperative ultrasound imaging were measured and calculated. Correlations between intraoperative ultrasound metrics, MRI metrics, and the recovery rate JOA scores were analyzed using Spearman correlation analysis. @*Results@#The postoperative JOA scores improved significantly, with a mean recovery rate of 65.0 ± 20.3% (p < 0.001). No significant correlations were found between the operative ultrasound metrics and MRI metrics. The gray value ratios of the spinal cord hyperechogenicity was negatively correlated with the recovery rate of JOA scores (ρ = -0.638, p = 0.001), while the ventral and dorsal gray value ratios of spinal cord hyperechogenicity were negatively correlated with the recovery rate of JOA-motor scores (ρ = -0.582, p = 0.004) and JOA-sensory scores (ρ = -0.452, p = 0.035), respectively. The dorsal gray value ratio was significantly higher than the ventral gray value ratio (p < 0.001), while the recovery rate of JOA-motor scores was better than that of JOA-sensory scores at 12 months post-surgery (p = 0.028). @*Conclusion@#For degenerative cervical myelopathy, the correlations between intraoperative ultrasound and preoperative T2W MRI metrics were not significant. Gray value ratios of the spinal cord hyperechogenicity and dorsal and ventral spinal cord hyperechogenicity were significantly correlated with neurological recovery at 12 months postoperatively.
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Objective@#To analyze the correlations between intraoperative ultrasound and MRI metrics of the spinal cord in degenerative cervical myelopathy and identify novel potential predictive ultrasonic indicators of neurological recovery for degenerative cervical myelopathy. @*Materials and Methods@#Twenty-two patients who underwent French-door laminoplasty for multilevel degenerative cervical myelopathy were followed up for 12 months. The Japanese Orthopedic Association (JOA) scores were assessed preoperatively and 12 months postoperatively. Maximum spinal cord compression and compression rates were measured and calculated using both intraoperative ultrasound imaging and preoperative T2-weight (T2W) MRI. Signal change rates of the spinal cord on preoperative T2W MRI and gray value ratios of dorsal and ventral spinal cord hyperechogenicity on intraoperative ultrasound imaging were measured and calculated. Correlations between intraoperative ultrasound metrics, MRI metrics, and the recovery rate JOA scores were analyzed using Spearman correlation analysis. @*Results@#The postoperative JOA scores improved significantly, with a mean recovery rate of 65.0 ± 20.3% (p < 0.001). No significant correlations were found between the operative ultrasound metrics and MRI metrics. The gray value ratios of the spinal cord hyperechogenicity was negatively correlated with the recovery rate of JOA scores (ρ = -0.638, p = 0.001), while the ventral and dorsal gray value ratios of spinal cord hyperechogenicity were negatively correlated with the recovery rate of JOA-motor scores (ρ = -0.582, p = 0.004) and JOA-sensory scores (ρ = -0.452, p = 0.035), respectively. The dorsal gray value ratio was significantly higher than the ventral gray value ratio (p < 0.001), while the recovery rate of JOA-motor scores was better than that of JOA-sensory scores at 12 months post-surgery (p = 0.028). @*Conclusion@#For degenerative cervical myelopathy, the correlations between intraoperative ultrasound and preoperative T2W MRI metrics were not significant. Gray value ratios of the spinal cord hyperechogenicity and dorsal and ventral spinal cord hyperechogenicity were significantly correlated with neurological recovery at 12 months postoperatively.
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Objectives:To investigate the clinical outcome of Smiley face rod fixation system for lumbar isthmic spondylolysis.Methods:From January 2016 to June 2017,18 patients with isthmic spondylolysis were treated with smiley face screw-rod fixation system.There were 13 males and 5 females,with an average age of 28.2±3.2(25-32) years old.The average disease duration was 16.3±5.7(7-24) months.L5 isthmic spondylolysis was involved in all cases.All patients had been followed up at 3 months and 1 year after surgery.The preoperative and postoperative visual analogue scale(VAS) and Oswestry disability index(ODI) were compared.The X-ray and CT scan were evaluated to analyze the change of range of motion in the lumber spine and the bony fusion rate.Results:The mean operation time was 90.0±24.1 minutes.The average blood loss was 140±15ml.The average follow-up was 18.5±5.0 (12-24) months.The VAS at 3 months after operation was 3.0±1.2,and the ODI was (17.2±4.5)％ respectively,which showed significant differences compared with the preoperative ones[7.3±2.5 and (67.0±15.1)％](P＜0.05).The VAS and ODI at 1 year after operation were 1.0± 0.6 and (9.1±5.3)％,which showed significant differences compared with 3 months postoperation(P＜0.05).The range of motion between L5 and S1 was 13.1°±2.1° and the incidence of lumbar instability was 83.3％(15/18) preoperatively;it was 9.3°±1.6° and 11.1％(2/18) postoperatively,and there was statistic difference(P＜0.05).All patients achieved bone fusion in the isthmic defect 1 year after operation.Conclusions:The Smiley face rod fixation is a reliable treatment for lumbar spondylolysis with the advantage of minimal invasive,less nerve interference,and to restore normal anatomical structure,maintain the lumbar spine stability.
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BACKGROUND:Whether controling of post-injury inflammatory response combined with neural stem cel (NSC) transplantation can improve the curative efficacy for spinal cord injury stil remains unclear. OBJECTIVE:To investigate the repair of spinal cord tissue, myelin regeneration, axon regeneration, motor function recovery and the possible mechanism after early application of tumor necrosis factor α antagonist (Etanercept) combined with tyrosine kinase C (TrkC) gene-modified NSC transplantation. METHODS:TrkC-overexpressed NSCs (TrkC-NSCs) were constructed by lentiviral transfection technique. The rat models of spinal cord transection injury were prepared, and then subjected to Etanercept combined with TrkC-NSCs transplantation. The number of neurons and neuroregeneration after injury were measured by Nissl's staining, immunofluorescence and western blot. The rat motor function was detected by Basso Beattie Bresnahan score and evoked potential. The myelin regeneration was detected by electron microscopy and toluidine blue staining. RESULTS AND CONCLUSION:Compared with the other groups, the Etanercept combined with TrkC-NSCs transplantation group had more survived anterior horn motor neurons at 28 days after injury, more myelin-encapsulated axons, higher Basso Beattie Bresnahan score, greater amplitude of the evoked potentials, and relatively shorter latency (alP < 0.05). These findings indicate that early application of tumor necrosis factor-α antagonist combined with TrkC-NSCs transplantation after spinal cord injury in rats can effectively promote myelin regeneration, axon regeneration, and further promote motor function recovery.
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Objective To synthesize 18F labeled N-(2-18 F-fluoropropionyl)-L-glutamine (18 F-FPGLN) for tumor PET imaging,and to perform its biodistribution study on normal mice and PC-3 tumorbearing nude mice.Methods 4-nitrophenyl-2-18F-fluoropropionate (18F-NFP) was synthesized on the MF2V-IT-I synthesizer and was purified by semi-preparative HPLC.Anhydrous 18F-NFP was added to a solution of L-glutanine t-butyl ester to synthesize 18F-FPGLN t-butyl ester,which was hydrolyzed by HCl (3 mol/L) and neutralized with NaOH (2 mol/L) solution.18F-FPGLN product was collected for further study.Biodistribution study was performed on normal Kunming mice and PC-3 prostate cancer tumor-bearing nude mice,respectively.Results 18F-FPGLN was synthesized with 10％-15％ (decay uncorrected) overall radiochemical yield after 130 min of radiosynthesis.The radiochemical purity was higher than 96％.Rapid and high uptake of radiotracer was observed within the kidneys,and was quickly excreted through the urinary bladder.The uptake in kidney reached (35.0±1.2) ％ID/g at 5 min post-injection,and descended to (1.5±0.3) ％ID/g at 120 min.The liver,lung,heart and small intestine showed relatively moderate uptake of radioactivity.The uptake in the pancreas,muscle,spleen,stomach and brain was low,and the lowest uptake of (1.5±0.3) ％ID/g was found in the brain at 30 min post injection.High accumulation of 18F-FPGLN in PC-3 xenograft was observed,and the tumor/muscle ratio reached 2.07 at 60 min post injection.Conclusion A novel N-position 18F-labeled glutamine analogs 18F-FPGLN,with favorable pharmacokinetic characteristics,is synthesized successfully,which makes it possible to perform tumor PET imaging using 18F-FPGLN subsequently.
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BACKGROUND: Unstable cases of Hangman’s fracture or traumatic spondylilisthesis which are type II, IIa and III should be treated surgicaly. Retropharyngeal approach was employed in exposure of anterior upper cervical region. However, dissection and traction around important structures make the procedure complicated and increase the chance of nerve injury. OBJECTIVE:To evaluate the clinical curative effect and safety of an innovative operative technique in which a polyetheretherketone cage was used to perform cervical spinal fusion for the treatment of Hangman’s fracture. METHODS: Eight patients with type II or IIa Hangman’s fracture were enroled in this study and received cervical fusions at C2/3 levels. During folow-up postoperatively, they received X-ray examination. Fusion time and implant position were evaluated. The angle of deformity (α) and the displacement distance (β) were compared pre-operatively and 6-month post-operatively to measure reduction. The functional outcomes were also compared using the Post-Traumatic Neck Score (Mayo) pre-operatively and 6-month post-operatively, while neck pain was further investigated by Visual Analogue Scale score. RESULTS AND CONCLUSION:Al eight patients were folowed-up successfuly, with an average folow-up of 13 months (range 6-26 months). Compared with pre-operatively, Clinical Post-Traumatic Neck Score (Mayo) was increased, Visual Analogue Scale score, angle deformity (α) and displacement distance (β) were reduced at 6-month post-operatively (P < 0.05). Neck activity was not limited in final folow-up. Bone fusion was found in al patients at 3 or 6 months post-operatively, and no complication was detected. Results confirm that polyetheretherketone cage for type II and IIa Hangman’s fracture could achieve good outcomes and safety.
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Objective To evaluate the clinical outcome of mono-segment transpedicular fixation of type B thoracolumbar fracture.Methods A retrospective analysis was conducted on 40 cases suffering from type B thoracolumbar fracture treated with mono-segment transpedicular fixation from May 2003 to October 2012.According to the AO classification,13 cases were identified with type B1.1,11 type B1.2,11 type B2.2,2 type B3.1,2 type B3.2,and 1 type B3.3.Radiological results were evaluated by measuring compression rate of the fractured vertebra and Cobb' s angle of the vertebra adjacent to the fractured segment.Clinical results were assessed using Frankel classification for spinal cord injury and visual analogue scale (VAS) for pain.Results Mean operation time was 71 minutes and mean intrao perative blood loss was 105 ml.Mean period of follow-up was 47.5 months (range,24-82 months).Mean Cobb' s angle of the vertebra adjacent to the fractured segment and compression rate of the fractured vertebra revealed great correction at one week post-operation compared with preoperative ones (6.2° vs 20.1° and 10.1％ vs 38.9％ respectively,P ＜0.05) and there was no significant correction loss at the last follow-up (6.9° and 10.8％ respectively,P ＞ 0.05).Mean VAS was 8.6 points before operation,but mean VAS was 2.4 points at final follow-up (P ＜ 0.05).Neurological performance improved in 37 cases (93％).No cases experienced neurological deterioration.Conclusions Mono-segment transpedicular fixation has small incision,short operation time,few bleeding and decreased motor function loss.The procedure is indicated for most type B thoracolumbar fracture and clinical results are satisfactory.
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BACKGROUND:Bioabsorbable polymer materials used in interbody fusion are currently a hot research, and there is stil no consensus. OBJECTIVE:To summarize the basic research and clinical application of bioabsorbable polymer interbody fusion cages. METHODS:A search of literatures in the database of Wanfang, VIP and PubMed databases from January 1989 to June 2012 was performed with the key words of“intervertebral fusion;bioabsorbable;spine;animal experiment;clinical research”in Chinese and English, respectively. Al the literatures concerning bioabsorbable polymer interbody fusion cage were extensively reviewed, and current developments in the basic research and the clinical application of bioabsorbable polymer interbody fusion cage were investigated. RESULTS AND CONCLUSION:Basic researches show that bioabsorbable polymer cage can effectively promote interbody fusion, the main defect is the delayed inflammatory response and bulk erosion, and the degradation and fusion speed, mechanical strength and porosity need further studies. At present, the hybrid copolymer of polylactic acid and its derivatives is used in clinic and relevant research is being carried out. The main advantage of the material is that it is of flexibility to change parameters when used in fusion for different needs, but a good blood supply to tissues around the fusion cage and the osteogenesis effect are very important. Scaffold porosity and other key parameters can affect the mechanical properties of fusion cage to provide sufficient space to meet the requirement of cellmigration, angiogenesis, thereby promoting bone fusion, under the necessary pressure load. So, to find the optimal combination of parameters in the field of bone tissue engineering is stil a chal enge.
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Objective To investigate the feasibility of mono-segment pedicle instrumentation (MSPI)in management of thoracolumbar fracture (AO classification,A1 and A3) by being compared with short-segment(two-segment) pedicle instrumentation(SSPI).Methods Overall 141 patients with tape A1 or A3 thoracolumbar fractures,aged from 20 to 60 years (average,40.5 years),were enrolled in this prospective study.According to a simple randomized method,35 patients with type A1 fracture and 41 patients with type A3fracture were treated with MSPI,while 26 with type A1 fracture and 39 with type A3 fracture were treated with SSPI.Low back outcome score (LBOS) and ASIA2000 were used to evaluate clinical outcome.Eighteenth month postoperatively was assigned as the last follow up period.Wedge index (WI) and sagittal index (SI) of the affected vertebrae on radiography were measured and compared preoperatively,one week postoperatively and at the final follow-up.Results All patients were followed up successfully.The blood loss and duration of operation of MSPI group were significantly less than that of SSPI group,respectively.However,there were no significant differences of clinical outcome between two groups.For type A1 fracture,correction rate and correction loss of WI in MSPI group were better than those in SSPI group.For type A3 fracture,there were no significant differences of correction rate and correction loss of WI and SI between MSPI group and SSPI group; however,the failure rate of MSPI group was significantly higher than that of SSPI group.Conclusion For type A1 and partial type A3 thoracolumbar fractures,MSPI can provide the same or better fixation with less blood loss and operative duration than SSPI.Since MSPI for type A3.2 thoracolumbar fracture has a higher failure rate,the surgical indication should be strictly controlled.
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ObjectiveTo compare the clinical effect of posterior circumferential fusion with versus without intertransverse process fusion on lumbar instability in aged patients. MethodsThe elderly with lumbar instability were treated with the posterior instrumented circumferential fusion technique in 80 cases. Among 58 patients followed up for at least 2 years, 28 cases (group A)underwent posterior circumferential fusion with intertransverse process, while 30 cases (group B)without intertransverse process. X-ray examination was used before and 1, 3, 6, 12 and 24 months after operation to evaluate the fusion condition of the bone graft, and visul analogue scale (VAS) and Oswestry disability index (ODI) questionnaire were applied to assess the pain of center back and leg,and the conventional activity.ResultsThe operation time and blood loss were more in group A[(185.3±56.6) min and (376.3±92.9) m1] than in group B [(146.4±46.3) min and (234.3±64.5)ml (t=12.37, 37.49, P＜0.01)]. All the 58 cases were followed for at least 2 years. The 27 cases (96.4％) of group A and 28 cases (93.3％) of group B got bone fusion (x2 =0.004, P＞0.05).There were marked differences in the VAS of center back at 1 and 3 months after operation between the 2 groups (t=3.178, 2.158, both P＜0.05), while no difference at the other 3 time point. VAS about the leg pain and the ODI showed no differences between group A and B after operation (all P＞0.05). ConclusionsFor the lumbar instability in the elderly, the posterior circumferential fusion with or without intertransverse process fusion can achieve a similar high rate of fusion and satisfactory clinical results,andtheposteriorcircumferentialfusionwithoutintertranaverseprocess is recommended for less trauma.
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Objective To investigate the changes of somatosensory-evoked potential(SEP)during an mild impact spinal cord injury in rats 80 as to evaluate its potential value in prevention of such iatrogenic damage. Methods Twenty-four SD rats weighing(340±28)g were randomly divided into two groups,ie,sham control group(only exposure without impact at C6)and injury group(mild impact spihal cord injury at C6).SEP wss recorded in both groups.The changes of SEP in waveform,amplitude and latency were observed and compared between groups and between operations.The gross dissection and histologic analysis were performed after surgery for comparative study. Results SEP waveforms,amplitude and latency showed no significant change in the sham control group.In contrast,the SEP waveform and amplitude animals showed significant changes in the injury group after impact spinal cord injury and the amplitude was decreased from pre-injury(1.3±0.7)μV to post-injury(0.5±0.4)μV(P<0.05),while the latency showed no significant difference between(11.1±2.1)ms pre-injury and(10.7±1.3)ms post-injury(P>0.05).However,this abnormal change appeared in a temporary period at(5.7±3.2)minutes after impact and lasted for about(7.1±3.3)minutes.Diffused hemorrhagic nidus could be seen in the injured cord,which was not found in the sham control group. Condusions Mild impact spinal cord injury may induce transient abnormalities of SEP in waveform and amplitude,which requires careful monitoring in clinical practice.The sudden change in SEP may be associated with impact and vibration damage to the spinal cord,suggesting timely use of protection measures for spinal cord.
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ObjectiveThe aim in this study was to evaluate the efficacy of the ball tip probe technique in placing pedicle screws in patients.MethodsFrom May 2009 to June 2010,we used ball tip probe technique in pedicle screw placement in patients with scoliosis,spondylolisthesis,spinal fractures and other diseases.The ball tip probe consisted of a metal shaft with a metal ball-shaped tip whose size included 1.5,2.5,3.0,3.5 mm in diameter.The ball tip probe with a diameter of 1.5mm owned a high rigidity and certain flexibility.Ball tip probe technique:A high speed bur was used to remove cortical bone and create a starting point,and then the ball tip probes is tapped gently by a hammer for making a guide hole through the pedicle into the vertebral body.The accuracy of the pedicle screw placements was evaluated on postoperative axial CT scanning The pedicle screw placements was compared between the the ball tip probe group and conventional freehand technique group.ResultsThree hundred and twelve screws were evaluated in the ball tip group and 276 in the conventional freehand group.All the screws (100％) were in the desired pedicle in the ball tip group and 215 (78％) in the conventional group.In the conventional group,23 screws(8.3％) were classified as medial violation; 38(13.7％) as lateral violation.A significant difference was determined between the 2 groups regarding the pedicle breaches.No vascular,pulmonary,or neurological injuries caused by pedicle screws placement was found in either group.ConclusionThis study demonstrates the accuracy and reliability of the ball tip probe technique in pedicle screw placement.This technique can probably reduce the risk of complications of screw misplacements.
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BACKGROUND: Posterior lumbar non-fusion devices have been developed to control vertebral column movement, change load pattern of instability segment, restrict abnormal action, as well as avoid adjacent segment degeneration.OBJECTIVE: To investigate the efficiency of Wallis dynamic stabilization system in the treatment of lumbar vertebrae instability.METHODS: Ten cases suffering from lumbar instability were selected, including 3 males and 7 females, aged 43-65 years. One patient sustained L_(1/2) and L_(4/5) segmental instability, one was L_(2/3) and another was L_(3/4), and the others were L_(4/5). Two patients complicated with lumbar disc herniation and 7 patients combined with lumbar spinal stenosis at the same affected segment, and 3 patients associated with lumbar spinal stenosis at adjacent segment. All unstable segments were treated with decompression, posterior implantation of Wallis dynamic stabilization system. Visual analogue scale (VAS) and Japanese Orthopedic Association (JOA) scores for low back pain and Oswestry disability index (ODI) were used to evaluate clinical outcomes. In addition, therange of motion (ROM) at the instrumented segment and adjacent segments and posterior disc height (PDH) in standing and extension position at L_(4/5) segment were also measured.RESULTS AND CONCLUSION: All the patients were followed-up for 2-13 months, mean 9.2 months. The mean operation duration was 128 minutes (90-185 minutes), with bleeding volume of 264 Ml (50-600 Ml). Sings and symptoms of all patients were improved significantly after operation, except one patient with recurrence of L_(4/5) lumbar spinal stenosis at 3 month after surgery, whose symptoms relieved by revision with fenestration and decompression. The postoperative VAS was dramatically decreased than that of preoperation (P=0.003); the JOA score was obviously increased (P=0.002), and the ODI score was decreased (p=0.008). The postoperative range of motion decreased significantly (P<0.05). However, there was no obviously difference between preoperative and postoperative L_(3/4), L_5/S_1 and posterior disc height (P>0.05). Good clinical results can be achieved by surgical intervention with Wallis dynamic stabilization system in treating lumbar vertebrae instability.
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Objective To analyze and evaluate the effect of posterior circumferential fusion for treatment of the mechanical instability of lumbar spine, and discuss the relative merits,indications and contraindications in this procedure. Methods Two hundred and two patients with mechanical instability of lumbar spine treated by the posterior instrumented circumferential fusion technique from January 2001 to January 2007. One hundred and thirty-two patients were selected who were treated with only one segment fusion and followed up for at least 1 year, of them 97 patients suffered lumbar spondylolisthesis, 35 patients suffered degenerative lumbar instability. X-ray was used to evaluate the fusion condition of the bone graft, and VAS and ODI questionnaire were applied to assess the pain of back and leg,and the conventional function. Results All patients were followed up for 12-84 months, averaged (43±23) months,125 patients got bone fusion, accounted for 94.7%(125/132). The VAS of low back pain was (6.71 ± 1.31) points before operation, while (3.20 ± 1.14) points after operation (P < 0.05) ,and the VAS of leg pain was (8.33 ± 1.78) points before operation,while (4.31 ± 1.15) points after operation (P< 0.05). The ODI was (68.6 ± 14.7) % before operation, while (13.6 ± 1.5) % after operation (P < 0.05). Conclusions Posterior circumferential fusion is a positive and excellent treatment for the mechanical instability of lumbar spine. With its merits, the high fusion rate and good clinical results can be received.
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BACKGROUND:Antedor canulated screw has been considered an ideal method to treat odontoid fracture.OBJECTIVE:To compare the biomechanical properties of different anterior screws.DESIGN,TIME AND SETTING:A randomized contrast study was performed at the Biomechanics Laboratory of Southern Medical University from March to September 2006.MATERIALS:Double-thread canulated screws and single-thread canulated screws were made of titanium alloy and provided by Shuangyang Medical Apparatus Co.,Ltd.,Suzhou.METHODS:A total of head-neck complexes (C0-C3) which were collected from 20 corpses were maintained in formaldehyde for less than 3 months;thereafter,the muscles and ligaments were removed to obtain the axis specimens so as to make type Ⅱ odontoid fracture models.The fracture samples were individually treated with double-thread and single-thread canulated screws,with 10 samples for each group.MAIN OUTCOME MEASURES:The shear stiffness and the maximum resistance of the two kinds of screw were tested in this study.RESULTS:The shear stiffness of the double-thread screw group was significantly higher than the single-thread screw group (P＜0.01 );however,there was no significant different in the maximum resistance between the two groups (P＞0.05).CONCLUSION:Double-thread canulated screws have a strong biomechanical stability for treating odontoid fracture;therefore,the first choice of the internal fixation should be double-thread canuiated screws for patients with osteoporosis or those who are susceptible to expanded screw pathway during surgical procedures.
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BACKGROUND:Hydroxyapatite (HA) artificial bone,as bone grafting substitute,would not cause inflammatory reaction or immunological rejection and possesses good biocompatibility after transplantation into human body.It is a novel implant material with bone conduction ability.OBJECTIVE:To investigate the efficacy of HA artificial bone in bilateral open-door posterior cervical expansive laminoplasty and to make a comparison with autogenous bone.DESIGN,TIME AND SETFING:A retrospective case analysis was performed at the Department of Spine Surgery,Hungpuyuan Branch,the First Affiliated Hospital of Sun Yat-sen University from March 2001 to December 2008.PARTICIPANTS:Seventy patients with cervical spondylosis complicated by compression in 3 or more segments or by cervical stenosis and additional fifteen patients with cervical stenosis complicated by cervical trauma were included in this study.METHODS:A bilateral open-door posterior cervical expansive laminoplasty was performed,in which,23 patients received autogenous bone transplantation (autogenous bone group) and 62 patients underwent HA artificial bone transplantation (HA group).MAIN OUTCOME MEASURES:① Japanese Orthopaedic Association (JOA) score pdor to and after surgery,surgery time,and intraoperative bleeding.② HA artificial bone-host biocompatibility.RESULTS:All eighty-five patients were followed up for more than 3 months.There was no significant difference in JOA scores no matter prior to or after surgery between the autogenous bone and HA groups (P＞0.05).The surgery time averaged 85.2 minutes (range 65-110 minutes) in the HA group and averaged 116.4 minutes (range 75-150 minutes) in the autogenous bone group.The intraoperative bleeding averaged 210 mL (range 130-400 mL) in the HA group and averaged 260 mL (range 170-500 mL) in the autogenous bone group.There were no material-host response and other severe complications found in each group,except HA artificial bone fragmentation in 3 patients from the HA group.CONCLUSION:HA artificial bone yields good efficacy and causes fewer complications in bilateral open-door posterior cervical expansive laminoplasty;in addition,it requires less time for surgery and causes less bleeding.
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Objective To evaluate the clinical efficacy of monosegmental pedicle instrumentation in management of thoracolumbar burst fractures. Methods A total of 67 patients with traumatic thora-columbar burst fractures (type A3.1 and A3.2) were treated with monosegmental pedicle instrumentation in our department from October 2003 to February 2008. Imageologic effect was observed by measuring sagittal index and wedge index via X-ray and clinical outcomes evaluated by using low back outcome score. Results All operations were performed successfully, with average operation duration of 93 mi-nutes and average intraoperative blood loss of 157 ml. Of all, 65 patients were followed up for 4-27 months (average 19.8 months), which showed that all the patients achieved bony fusion, with no implant failure except for one with screw loosening. The sagittal index and wedge index were 13.06°and 42.9% preoperatively and 4.47° and 21.78% postoperatively, with statistical difference (P <0.01). The final follow-up showed no significant correction loss except for two patients (P < 0.05). The low back outcome scores of all patients at follow-up were improved significantly (P < 0.05). Conclusions Monoseg-mental pedicle instrumentation has advantages of minimal invasion, short operative duration, less blood loss and less vertebral motion segment loss and hence is an effective and reliable operative technique for thoracolumbar burst fractures.
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Objective To compare the biomechanical properties of mono-segTnent pedicle instru-mentation and its combination with bone cement fixation in treatment of thoracolumbar fractures. Meth-ods Eight fresh specimens of calf spines ( T11 -L3 ) were used for development of incomplete burst frac-ture models at the vertebral body of L1. Mono-segment pedicle instrumentation and its combination with vertebroplasty were respectively applied in each specimen subsequently to restore spinal stability. A cyclic loading with pure moment of 4 Nm was applied to specimens, with load frequency of 0.5 Hz for 2 000 cy-cles. Range of motion (ROM) at flexion/extension, left/right lateral bending and left/right axial rotation of the fixated segment at different status of intact, injury, fixation and cyclic loading was determined by spinal three-dimensional instability test system. Results ROM after treatment with two fixation tech-niques and that at different directions after cyclic loading were distinctly smaller than that of intact and fractured models (P <0.05 ). Under mono-segment pedicle instrumentation combined with bone cement fixation, ROM at flexion, extension, lateral bending and axial rotation was 0.40°, 0. 53°, 0.86° and 0.55° respectively and that after cyclic loading was 0.10°, 0.07°, 0.19° and 0.08°respectively, which were all lower than those of monosegmental fixation, especially at flexion and axial rotation, with statisti-cal difference (P <0.05 ). Conclusions Both fixation techniques can provide instant stabihty of the fractured spine and have good fatigue resistance effect. However, mono-segment pedicle instrumentation is inferior to mono-segment pedicle instrumentation plus bone cement fixation in treatment of fractured verte-bral body at flexion and axial rotation.
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Objective To evaluate the safety and efficacy of one-level posterior lumbar interbody fusion(PLIF) combined with Prospace and facet fusion using local autograft. Methods Clinical and radiographic data of 76 patients treated by this technique was reviewed from May 2002 to December 2004. Of them, there were 52 males and 24 females, with an average age of 53.2 years (23-81 years), including 60 cases of degenerative disc disease, 9 cases of failed back surgery syndrome and 3 cases of spondylolysis. The disese courses were 1.2-8.7 years (mean 3.6 years). The levels of PLIF were: L2,3 in 2 cases, L3,4 in 7, L4,5 in 54, L5/S1 in 10, L4/S1 in 1 and L5,6 in 2. After decompression, Prospace was inserted into interbody space bilaterally,and located in disc space 4 mm beyond the rear edge of the vertebral body. Local laminectomy autograft was packed both laterally into and between 2 implants. Then the remanent local autograft was placed over facet bed. Pedicle screws were used after insertion of Prospace. Clinical results were evaluated by the JOA score. Disc height ratio and lumbar lordosis angles were measured on lateral radiographs. Fusion status was determined by evidence of bridge trabeculae across facet joint and interbody space on CT scan without mobility in lateral dynamic X-rays, and no radiolucent gap between Prospace and endplate. Paired t-test was used for statistical analysis. Results Mean blood loss and operative time was 384 ml and 178 minutes, respectively. The average JOA score at final follow-up (26.1 + 2.7) was significantly improved when compared with that of pre-operation (14.5 ± 4.0, P ＜ 0.05), with a mean recovery rate of JOA score 81.1% (37.5%-100.0%). The fusion rate was 97.4% (74/76). Mean disc height ratio and the involved segmental lordosis angle were increased from preoperative 0.27 ±0.07 and 5.8 + 2.2° to 0.33 + 0.06 and 11.3 + 2.0° respeetively at the final follow-up, and the differences were significant ( P ＜ 0.05). There were no device-related complications. Conclusion This surgical technique combined with Prospace interbody device is a safe and effective surgical option for patients with one-level lumbar disorders when PLIF is warranted.