Objective To investigate the early effectiveness of Zero-profile interbody fusion system (Zero-P) in the treatment of cervical disc protrusion. Methods Between October 2010 and June 2012, 25 patients with cervical disc protrusion underwent anterior cervical discectomy and fusion (ACDF) using the Zero-P system. There were 15 males and 10 females, aged from 35 to 68 years (mean, 49 years). The disease duration was 3-26 months (mean, 10.5 months). Single segment was involved in all cases (2 cases in C3, 4, 5 cases in C4, 5, 11 cases in C5, 6, and 7 cases in C6, 7). The operation time and blood loss were recorded and analyzed. The visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, and neck disability index (NDI) were used to assess pain and nerve function improvement; the cervical Cobb angle was measured on the X-ray films before and after operation; according to Pitzen’s criteria, intervertebral fusion was evaluated. Results The operation was successful in 25 patients, with no severe complication. The average blood loss was 42.6 mL (range, 20-120 mL). The average operation time was 63.6 minutes (range, 45-90 minutes). Primary healing of incision was obtained in all cases; no injury of spinal cord and nerve root, cerebrospinal leakage, or deep infection occurred. The patients were followed up 6-23 months (mean, 14.5 months). No Cage subsidence and loosening, breaking, or pulling-out were observed. The symptoms and curvature of the cervical spine were obviously improved in all patients after operation. The VAS score, JOA score, NDI, and the cervical Cobb angle at 3 months and last follow-up showed significant differences when compared with preoperative ones (P lt; 0.05), but no significant difference was found between at 3 months and at last follow-up (P gt; 0.05). The interbody fusion was achieved in each operated segment of all patients according to Pitzen’s criteria. Conclusion The early effectiveness of ACDF with Zero-P system is satisfactory in treatment of cervical disc protrusion because it has the advantages of short operation time, less bleeding, good stability and restoration of the cervical alignment.
Objective To study the prevention and management of early compl ications associated with anterior cervical spinal surgery. Methods From November 1998 to December 2006, 363 cases were treated with anterior cervicalsurgery, including 268 males and 95 females aged 17-79 years．In these cases, 224 suffered from cervical spondylosis, 39 from cervical disc herniation, 87 from cervical trauma, 9 from cervical tumor and 4 from cervical tuberculosis. Forty-eight cases with anterior cervical surgery were fused by autogenous il iac bones, 132 cases with anterior cervical surgery were fused by autogenous il iac bones and anterior cervical spine locking plates, and 183 cases with anterior cervical surgery were fused by titanium mesh cage and anterior cervical spine locking plates. Results A total of 282 cases were followed up for 3 months to 5 years with the average of 1 year and 11 months. Twenty-three compl ications associated with surgery were found, with an incidence of 8.16%. Three cases of transient superior laryngeal nerve palsy recovered within 3-7 days after the restriction of l iquid diet and fluid replacement. Two cases of recurrent laryngeal nerve palsy recovered by 3-month pronunciation practice. One case of spinal cord injury was treated with medicine for dehydration and anti-inflammation, and was restored to preoperative muscle power of inferior extremity after 6 months. Two cases of CSF leakage were cured with moderate local compression and meticulous water-tight wound closure. Among the 10 patients with compl ications of internal fixation, one suffering mild dysphagia was reoperated, while the others were treated with cephal-cervico-thorax plaster external fixation and recovered with sol id fusion within 3-18 months. Among the 4 cases with cervical hematoma, 1 died of wrong rescue procedures and 1 was infected. Conclusion Adequate preoperative preparation, thorough understanding of anatomy related to the anterior approach and skilled surgical technique are essential for preventing the early postoperative compl ications of anterior cervical spinal surgery．
Objective To evaluate the cl inical outcomes and values of anterior segmental decompression and double-plate fixation (ASDDF) for treatment of ski p cervical spondylotic myelopathy (SCSM). Methods Between June 2005 and June 2008, 17 patients with SCSM were treated with ASDDF. There were 10 males and 7 females with an average age of 58.8 years (range, 41-74 years) and an average disease duration of 9.7 months (range, 6-39 months). According to JapaneseOrthopaedic Association (JOA) score system, 2 patients were rated as extreme severe condition, 7 as severe, 7 as moderate, and 1 as mild. MRI images showed 42 affected cervical disc levels, including 26 disc levels with high-intensity intramedullary lesions on T2, 4 with low-intensity intramedullary lesions on T1, and 12 with significant cord compression but no signal change; according to Nagata classification scale, there were 5 abnormal segments at class I, 21 at class II, and 16 at class III. The rate of fusion, the Cobb angle, and the range of motion (ROM) of the cervical spine were measured preoperatively and postoperatively by the X-ray examinations. The improvement of the neurological function was evaluated by the JOA score. Results The average time of follow-up was 28.6 months (range, 24-58 months). After operation, dysphagia occurred in 2 cases (symptom rel ief after 1 month), hoarseness in 1 case (symptom rel ief after 3 months of methylcobalamin treatment), and degeneration of adjacent segments without symptom in 3 cases. The X-ray films showed the fusion rate of 100% at 12 months after operation without displacement, resorption or collapse of bone graft, and without breakage or loosening of plate and screw. The Cobb angles were (13.3 ± 10.4)° preoperatively, (15.8 ± 10.8)° immediately postoperatively, and (15.4 ± 11.4)° at last follow-up; the ROM of the cervical spine were (41.3 ± 17.4)° preoperatively and (23.8 ± 18.8)° at last follow-up; and the JOA scores were 8.2 ± 2.9 preoperatively, 13.7 ± 3.0 at 12 months postoperatively, and 13.9 ± 2.8 at last follow-up. All indexes showed significant differences between before operation and after operation (P lt; 0.05). The results of JOA scores were excellent in 8 cases, good in 6, fair in 2, and poor in 1 with an average improvement rate of 66.8% (range, 14%-88%) for the neurological function. Conclusion Adequate decompression, high rate of fusion, sol id mechanical stabil ity, improvement of total cervical lordosis,and the neurological function can be achieved through ASDDF for treatment of SCSM.
Objective To explore the injury mechanism of the severethoracolumbar burst fracture and the necessity of anterior decompression and reconstruction with internal fixation. Methods From January 1999 to January 2004, 21 patients were treated with anterior decompression and reconstruction. The fractures were located at T12 in 6 patients, L1 in12, L2 in 4, L3 in 3,and L4 in 1. Four patients were treated with the “anterior approach” and “posterior approach” surgeries for severe column fractures.Results All the patients were restored to the normal physiological radian, and the spinal canal was decompressed completely. They werefollowed up for 1-6 years, and the bony fusion was observed radiologically.The spinal cord function was improved to the 1-3 Frankel grade in all the patients except 2. There were no such complications as leakage of the cerebrospinal fluid, platescrew loosening or breaking, or segment instability. The clinical effects were satisfactory. Conclusion The operation of the anterior decompression and reconstruction with internal fixation for severe thoracolumbar burst fracture has advantages of complete decompression, full bonegrafting, and firm internal fixation. It canrestore the spinal height and improve the spinal cord function.
Objective To improve the safety of the percutaneous anterior transarticular screw fixation (PATSF) by measuring the parameters related to PATSF. Methods Spiral CT scan and three-dimensional reconstructions of the atlantoaxis were performed in 50 adult volunteers. The section of inner margin of atlantal superior articular facet, the coronal plane ofvertebral artery cavity, and the sagittal plane of atlano-axis were obtained with multiplanar reconstruction on hel ical CT. The atlantoaxial vertebral structure and the direction of vertebral artery cavity were observed. The parameters related to PATSF were measured and analysed. Results The suitable position of screw insertion was 4.0 mm from the midpoint of the axoidean anteroinferior margin. The maximum external angle of PATSF was (29.89 ± 1.41)°; the minimum external angle was (4.37±0.87)°; the maximum backward angle was (32.41 ± 1.66)°; the optimal external angle was (17.13 ± 0.88)°; the optimal backward angle was (17.62 ± 1.03)°; and the optimal screw length was (41.57±0.79) mm. The atlantoaxial articular facial diameter was (16.71 ± 1.61) mm; the maximum distance of atlantal lateral displacement was (6.96 ± 1.09) mm; and the ratio of them was 41.80% ± 5.69%. Conclusion The optimal insertion of PATSF is safe and rel iable. The screw can be inserted when the displacement of the atlantal lateral mass is in a certain degree.
ObjectiveTo explore the effectiveness and safety of tranexamic acid (TXA) in anterior approach surgery for thoracolumbar fractures.MethodsFrom January 2017 to January 2020, a total of 68 thoracolumbar fracture patients undergoing anterior approach surgery were included and randomly divided into TXA group (n=33) and control group (n=35). Patients in the TXA group were given a dose of 15 mg/kg of TXA by intravenous infusion during 30 min before skin incision and an additional 15 mg/kg of TXA intravenously at 8 h after the first infusion, while the ones in the control group were given 15 mg/kg of normal saline at the same time. Basic data of the patients were collected. The hemoglobin concentration, hematocrit, coagulation and fibrinolysis indexes of the patients were monitored preoperatively, 24-hour postoperatively, and 72-hour postoperatively. The intraoperative blood loss and wound drainage of the patients were recorded. The incidence of blood transfusion and thrombotic events were collected. Statistical analysis was performed.ResultsThere was no significant difference in age, sex, body mass index, operation time, fracture location distribution, anesthesia classification of American Society of Anesthesiologists, neurologic grade of American Spinal Injury Association, injury time, or length of hospital stay between the two groups (P>0.05). Compared with those in the control group, the total blood loss [(1 398.49±312.24) vs. (1 642.30±357.78) mL, P=0.003], intraoperative blood loss [(432.83±74.76) vs. (486.31±86.51) mL, P=0.008], and wound drainage [(276.73±89.42) vs. (389.24±125.71) mL, P<0.001] in the TXA group reduced. No statistically significant difference was found between the two groups in the preoperative hemoglobin or hematocrit (P>0.05), but the 24-hour postoperative hemoglobin concentration [(112.67±20.59) vs. (102.64±19.41) g/L, P=0.042] and hematocrit [(32.25±4.12)% vs. (30.13±4.28)%, P=0.042] in the TXA group were higher than those in the control group. The incidence of allogeneic blood transfusion in the TXA group was lower than that in the control group (6.1% vs. 25.7%, P<0.05). There was no statistically significant difference in preoperative, 24-hour postoperative, or 72-hour postoperative prothrombin time, international standardized ratio, activated partial prothrombin time, platelet count, fibrinogen, d-dimer, or fibrinogen degradation products between the two groups (P>0.05), and no thrombotic complications were found.ConclusionTXA has good efficacy and safety in the anterior approach surgery for thoracolumbar fractures.
Objective To compare the biomechanical properties of the anterior transpedicular screw-artificial vertebral body (AVB) and conventional anterior screw plate system (AP) in lower cervical spine by finite element study. Methods CT images (C1-T1) were obtained from a 38-year-old female volunteer. The models of intact C3-7 (intact group), AP fixation (AP group), and AVB fixation (AVB group) were established and analyzed by Mimics 14.0, Geomagic Studio 2013, and ANSYS 14.0 softwares. The axial force of 74 N and moment couple of 1 N·m were loaded on the upper surface and upper facet joint surfaces of C3. Under conditions of flexion, extension, lateral bending, and rotation, the Von Mises stress distribution regularity and maximum equivalent stree of AP and AVB groups were recorded, and the range of motion (ROM) was also analyzed of 3 groups. Results The intact model of lower cervical spine (C3-7) was established, consisting of 286 382 elements and 414 522 nodes, and it was successfully validated with the previously reported cadaveric experimental data of Panjabi and Kallemeyn. The stress concentrated on the connection between plate and screw in AP group, while it distributed evenly in AVB group. Between AP and AVB groups, there was significant difference in maximum equivalent stress values under conditions of 74 N axial force, flexion, extension, and rotation. AVB group had smaller ROM of fixed segments and larger ROM of adjacent segments than AP group. Compared with intact group, whole ROM of the lower cervical spine decreased about 3°, but ROM of C3, 4 and C6, 7 segments increased nearly 5° in both AP and AVB groups. Conclusion As a new reconstruction method of lower cervical spine, AVB fixation provides better stability and lower risk of failure than AP fixation.
Objective To compare the loss of anterior column heightand cervical Cobb angle with three different types of anterior cervical discectomy and fusion(ACDF). Methods A prospective randomized study was performed on 60 patients who had undergone ACDF with the autologous iliac crest graft (group A, n=20), the autogenous bone and the anterior cervical locking plates (group B, n=20), and Syncage-C filled with the local autograft reamings (group C, n=20) from January 1998 to January 2003. The patients diagnosed as having cervical radiculopathy (RP) and cervical spondylotic myelopathy (CSM) were indicated for ACDF. Of the patients, 41 were male and 19 female with a mean age of 57 years (range, 36-68) and their average course of disease was 6.2 months (range, 1-36). There were 36 one-level and 24 two-level fusions from C3,4 to C7,T1. Radiological measurements were performed on the cervical radiographs taken before operation, 7 days and 3 months after operation, and on the last day of the follow-up; then, the height and Cobb angle of the fused segment, functional restoration, and clinical outcome were evaluated in the three groups. Results The followup of more than 2 years (range,2-7) showed that the average loss of anterior column height and Cobb angle of the fused segments in groups A and B, which had not preserved the-endplate, hada greater increase than that in group C, which had preserved the endplate. Of the patients, 12 had autograft collapse, 3 autograft displacement, and 10 postural abnormality between the fused segments, most of which happened in groups A andB. The fusion rate was 93.3% (56 cases) according the strict arthrodesis critera; their excellent and good rate in the functional assessment was 83.3% (RP 90.4%, CSM 79.5%); the overall satisfactory (excellent and good) rates in groups A,B and C were 75%, 85% and 90%, respectively. Conclusion To increase the resistance to graft subsidence, which is a major reason for narrowness of the fused segments, and to maintain normal cervical curvature, we should improve our skills of bone grafting performance, preserve the endplate, carefully evaluate the degree of osteoporosis before operation, and use anterior cervical locking plate and /or fusion with Syncage-C when necessary.